BRPI0609818B1 - FIBER OBTAINED FROM OR COMPRISING MULTIBLOCK PROPYLENE INTERPOLYMER / A-OLEFIN, FIBER OBTAINED FROM OR UNDERSTANDING MULTI-BLOCK OF PROPYLENE INTERPOLYMER AND α-OLEFIN - Google Patents

Description

"FIBER OBTAINABLE FROM OR UNDERSTANDING A PROPILENE / A-OLEFINE MULTIBLOCK INTERPOLYMER FIELD OF THE INVENTION The invention relates to fibers made from propylene / α-olefin copolymers and methods for making fibers, and products made from fibers.

Background of the invention Typically, fibers are classified according to their diameter. Generally, single-strand fibers are defined as those having an individual fiber diameter greater than about 15 denier, usually greater than about 30 denier per filament. In general, thin denier fibers are those having a diameter of less than about 15 denier per filament. Generally, micro denier fibers are defined as those having a diameter of less than 100 microdenier per filament. Fibers can also be classified by the process used to produce them, such as single filament fibers, continuous thin filament wound fibers, short or short cut fibers, spunbond fibers, and expanded melt fibers.

Fiber with excellent elasticity is required to manufacture a variety of cloths, which in turn are used to manufacture a large amount of durable articles such as sportswear and furniture upholstery. Elasticity is a performance attribute, and is a measure of a cloth's ability to conform to a user's body or the structure of an item. Preferably, the cloth will maintain its conformation adjustment during repeated use, body extensions and retractions, and other elevated temperatures (such as those experienced during washing and drying of the cloth).

Typically, fibers are characterized as elastic if they have a high percentage of elastic recovery (i.e., low percentage of permanent deformation) after application of an inclined force. Ideally, elastic materials are characterized by a combination of three important properties: (I) a low percentage of permanent deformation, (II) a low stress or strain on deformation, and (III) a low percentage of stress or stress relaxation. . In other words, elastic materials are characterized by having the following properties: (I) a low load or tension requirement to stretch the material, (II) no or low stress or load relaxation when the material is stretched, and ( III) full or elevated recovery to original dimensions after stopping stretching, tilting or deformation.

Spandex is a segmented polyurethane elastic material known to exhibit nearly ideal elastic properties. However, spandex is cost prohibitive for many applications. In addition, spandex exhibits low environmental resistance to ozone, chlorine and high temperature, especially in the presence of moisture. Such properties, particularly the lack of chlorine resistance, cause spandex to have distinct disadvantages in garment applications such as beachwear and white clothing that desirably are washed in the presence of chlorine bleach.

A variety of thermoplastic fibers and cloths have been produced, such as polypropylene, very branched low density polyethylene (LDPE) typically produced by a high pressure polymerization process, heterogeneously branched linear polyethylene (e.g. low density linear polyethylene prepared using Ziegler catalysis), heterogeneously branched linear polypropylene and polyethylene mixtures, heterogeneously branched linear polyethylene mixtures, and ethylene / vinyl alcohol copolymers.

Despite advances in the art, there is a continuing need for polyolefin-based elastic fibers that are light and soft to body movement. Preferably, such fibers would have relatively high elastic recovery and would be produced with relatively high operational productivity. In addition, it would be desirable to form fibers that do not require slow processing steps but still provide soft and comfortable non-sticky cloths.

Summary of the Invention The above mentioned needs are met by various aspects of the invention. In one aspect, the invention relates to a fiber obtainable from or comprising a propylene / α-olefin interpolymer, wherein the propylene / α-olefin interpolymer is characterized by one or more of the following properties: Mw / Mn from about 1,7 to about 3,5 at at least one melting point, Tm, in degrees Celsius, and density, d, in grams / cubic centimeter, where the numerical values of Tm and d correspond to the ratio: Tm -2002.9 + 4538.5 (d) - 2422.2 (d) 2; or (b) have Mw / Mn from about 1,7 to about 3,5, and are characterized by a heat of fusion, Δ em, in J / g, and a delta amount, ΔΤ, in degrees Celsius defined as temperature difference between the highest DSC peak and the highest CRYSTAF peak, with the numerical values of ΔΤ and ΔΗ having the following relationship: ΔΤ> -0.1299 (ΔΗ) + 62.81 for ΔΗ greater than zero and up to 130 J / g, and ΔΤ> 48 ° C for ΔΗ greater than 130 J / g, the CRYSTAF peak being determined using at least 5 percent of the cumulative polymer, and if less than 5 percent of the polymer has a identifiable CRYSTAF peak, so the CRYSTAF temperature will be 30 ° C; or (c) have an elastic recovery, Re, 300 percent creep percentage and 1 cycle measured with a compression molded interpolymer film, and have a density d, in grams / cubic centimeter, where Re ed values satisfy the following relationship when the interpolymer is substantially free of a crosslinked phase: Re> 1481-1629 (d); or (d) have a molecular fraction eluting between 40 ° C and 130 ° C when fractionated using TREF, characterized in that the fraction has a comonomer molar content of at least 5 percent, greater than that of a comparable fraction of TREF. random ethylene interpolymer eluting between the same temperatures, said comparable ethylene interpolymer having the same comonomers and a melt index, density, and a comonomer molar content (based on the entire polymer) within 10 percent of that of the interpolymer; or (e) have a storage module at 25 ° C, G '(25 ° C), and a storage module at 100 ° C, G' (100 ° C), with the ratio of G '(25 ° C) C) for G '(100 ° C) is from about 1: 1 to about 10: 1. (f) having at least one molecular fraction eluting between 40 ° C and 130 ° C when fractionated using TREF, characterized in that the fraction has a block index of at least 0.5 and up to about 1 and a distribution of molecular weight, Mw / Mn, greater than about 1.3; or (g) have an average block index greater than zero and up to about 1.0 and a molecular weight distribution, Mw / Mn, greater than about 1.3.

In another aspect, the invention relates to a fiber obtainable from or comprising at least one propylene interpolymer and a C2 or C4-C20 α-olefin, wherein the interpolymer has a density of about 0.860 g. / cm3 at about 0.895 g / cm3 and permanent deformation at 70 ° C less than about 70%. In some embodiments, permanent deformation at 70 ° C is less than about 60%, less than about 50%, less than about 40%, or less than about 30%.

In some embodiments, the interpolymer satisfies the following ratio: Re> 1491-1629 (d);

Re> 1501-1629 (d); or Re 1511-1629 (d).

In other embodiments, the interpolymer has a melt index of from about 0.1 to about 2000 g / 10 minutes, from about 1 to about 1500 g / 10 minutes, from about 2 to about 1000 g. g / 10 minutes, from about 5 to about 500 g / 10 minutes, measured according to ASTM D-1238, condition 192 ° C / 2.16 kg. In some embodiments, the propylene / α-olefin interpolymer has Mw / Mn of 1.7 to 3.5 and is a randomized block copolymer comprising at least one hard block and at least one soft block. Preferably, the propylene / α-olefin interpolymer has a density in the range of from about 0.86 to about 0.96 g / cm3 or from about 0.86 to about 0.92 g / cm3. In other embodiments, the propylene / α-olefin interpolymer is mixed with another polymer.

"Α-olefin" in "propylene / α-olefin interpolymers" or "propylene / α-olefin / diene interpolymers" refers herein to α2-olefins of C2 or higher (such as C3 or higher olefins). In some embodiments, α-olefin is styrene, propylene, 1-butene, 1-hexene, 1-octene, 4-methyl-1-pentene, 1-decene, or a combination thereof and diene is norbornene, 1, 5-hexadiene, or a combination.

The fiber is elastic or inelastic. Sometimes the fiber is crosslinked. Crosslinking can be accomplished by photon irradiation, electron beam irradiation, or by a crosslinking agent. In some embodiments, the percentage of crosslinked polymer is at least 20 percent, such as from about 20 percent to about 80 percent or from about 35 percent to about 50, measured by weight percent of. formed gels. Sometimes fiber is a two-component fiber. The two-component fiber has a wrap-core structure; an island structure in the sea; a side-by-side structure; a matrix-fibril structure; or a segmented pi structure. The fiber may be a short fiber or an adherent fiber. In some embodiments, the fiber has a coefficient of friction of less than about 1.2, and the interpolymer is not mixed with any filler.

In some embodiments, the fiber has a diameter in the range of from about 0.1 denier to about 1000 denier and the interpolymer has a melt index of about 0.5 to about 2000 and a density of about 0.865 g / cm3 to about 0.955 g / cm3. In other embodiments, the fiber has a diameter in the range of from about 0.1 denier to about 1000 denier and the interpolymer has a melt index of about 1 to about 2000 and a density of about 0.865 g / cm3 to about 0.955 g / cm3. In still other embodiments, the fiber has a diameter in the range of from about 0.1 denier to about 1000 denier and the interpolymer has a melt index of about 3 to about 1000 and a density of about 0.865 g / cm3. at about 0.955 g / cm3.

In yet another aspect, the invention relates to a cloth comprising fibers produced in accordance with various embodiments of the invention. The cloths can be woven, melt expanded, gel woven, solution woven, etc. The cloths may be elastic or inelastic, woven or nonwoven. In some embodiments, the cloths have a percentage recovery in MD of at least 50 percent in 100 percent deformation.

In yet another aspect, the invention relates to a carded yarn or net comprising fibers produced in accordance with various embodiments of the invention. The wire of being covered or not covered. When covered, it can be covered by cotton yarns or nylon yarns.

In yet another aspect, the invention relates to a method for manufacturing fibers. The method comprises (a) fusing a propylene / α-olefin interpolymer (described herein); and extruding the propylene / α-olefin interpolymer into a fiber. The fiber may be formed by melt spinning, weaving, melt expansion, etc. In some embodiments, the cloth when formed is substantially free of cable formation. Preferably the fiber is stretched below the peak melting temperature of the interpolymer.

Additional aspects of the invention and features and properties of various embodiments of the invention become apparent from the following description.

Detailed Description of the Invention General Definitions "Fiber" means a material in which the length to diameter ratio is greater than about 10.

Typically, the fiber is classified according to its diameter. In general, filament fiber is defined as having an individual fiber diameter greater than about 15 denier, usually greater than about 30 denier per filament. Fine denier fiber generally refers to a fiber having a diameter of less than about 15 denier per filament. Generally, micro denier fiber is defined as fiber having a diameter of less than about 100 microdenier per filament.

"Filament fiber" or "single-filament fiber" means a course of undefined (i.e. undetermined) length, as opposed to a "short fiber" which is a discontinuous course of material of defined length (i.e. , a course that has been cut or otherwise divided into segments of a predetermined length).

"Elastic" means that a fiber will recover at least about 50 percent of its stretched length after the first pull and after the fourth to 100% strain (doubled the length). Elasticity can also be described by the "permanent deformation" of the fiber. Permanent deformation is the opposite of elasticity. The fiber is stretched to a certain extent and subsequently released to the original position before stretching, and then stretched again. The point at which the fiber begins to pull a load is referred to as the percent permanent deformation. "Elastic materials" are also referred to in the art as "elastomers" or "elastomeric". Elastic material (sometimes referred to as an elastic article) includes the copolymer itself as well, but not limited to the copolymer in the form of a fiber, film, strip, tape, strap, sheet, coating, mold and the like. The preferred elastic material is fiber. The elastic material may be cured or uncured, irradiated or non-irradiated, and / or crosslinked or non-crosslinked.

"Non-elastic material" means a material, for example a fiber, which is not elastic as defined above.

"Substantially cross-linked" and similar terms mean that the copolymer, molded or in the form of an article, has extractable xylenes of less than or equal to 70 weight percent (i.e. greater than or equal to 30 weight percent of content). preferably less than or equal to 40 weight percent (i.e., greater than or equal to 60 weight percent gel content). Extractable xylenes (and gel content) are determined according to ASTM D-2765.

"Homogeneous filament fiber" means a fiber that has a single polymer domain or region, and which has no other distinct polymer regions (as with two-component fibers).

"Two-component fiber" means a fiber that has two or more distinct polymer domains or regions. Two-component fibers are also known as conjugate or multicomponent fibers. Usually the polymers are different from each other although two or more components may comprise the same polymer. The polymers are arranged in substantially distinct zones along the cross section of the two component fiber, and usually extend continuously along the length of the two component fiber. The configuration of a two-component fiber may be, for example, a wrap-core arrangement (in which one polymer is surrounded by another), a side-by-side arrangement, a segmented pi arrangement, or an offshore arrangement. . Two-component fibers are further described in USP 6,225,243, 6,140,442, 5,382,400, 5,336,552 and 5,108,820.

"Melted expanded fibers" are fibers formed by extruding a thermoplastic polymer composition through a plurality of matrix capillaries, usually circular, thin as filaments or fillets in converging high-speed gaseous (e.g. air) streams that function. to attenuate the filaments or fillets to small diameters. The filaments or fillets are carried by high speed gaseous streams and deposited on a collecting surface to form a randomly dispersed fiber network with average diameters generally less than 10 microns.

"Fusion-spun fibers" are fibers formed by melting at least one polymer and then stretching the fiber into the melt to a diameter (or other cross-sectional shape) smaller than the diameter (or other cross-sectional shape) of the matrix. .

"Thermosolded fibers" are fibers formed by extruding a thermoplastic polymer composition fused as filaments through a plurality of usually circular, thin die matrix capillaries. The diameter of the extruded filaments is rapidly reduced, and then the filaments are deposited on a collecting surface to form a randomly dispersed fiber network with average diameters generally between about 7 and about 30 microns.

"Nonwoven" means a netting or cloth having a structure of individual fibers or threads which are randomly interleaved, but not in an identifiable manner such as an interlaced cloth. Elastic fiber according to embodiments of the invention may be employed to prepare nonwoven structures as well as structures composed of elastic nonwoven fabric in combination with non-elastic materials.

"Yarn" means a continuous length of twisted or otherwise tangled filaments which may be used in the manufacture of woven or interwoven fabrics and other articles. The wire may be covered or uncovered. Covered yarn is a yarn at least partially surrounded by an outer covering of another fiber or material, typically a natural fiber such as cotton or wool.

"Polymer" means a polymeric compound prepared by polymerizing monomers of the same or different types. The generic term "polymer" encompasses the terms "homopolymer", "copolymer", "terpolymer" as well as "interpolymer".

"Interpolymer" means a polymer prepared by polymerizing at least two different types of monomers. The generic term "interpolymer" includes the term "copolymer" (which is commonly used to refer to a polymer made from three different types of monomers). It also includes polymers produced by polymerizing four or more types of monomers.

The term "propylene / α-olefin interpolymer" refers to polymers with the majority molar fraction of the entire polymer being propylene. Preferably, the propylene comprises at least 50 mole percent of all polymer, more preferably at least 60 mole percent, at least 70 mole percent, or at least 80 mole percent, with the remainder of all polymer comprising at least least one other comonomer. For propylene / octene copolymers, the preferred composition includes a propylene content greater than about 80 mole percent with a octene content less than or equal to 20 mole percent. In some embodiments, propylene / α-olefin interpolymers do not include those produced in low yields or in minimal quantity or as a byproduct of a chemical process. Although propylene / α-olefin interpolymers may be mixed with one or more polymers, propylene / α-olefin interpolymers when produced are substantially pure and constitute the major component of a polymerization process.

Propylene / α-olefin interpolymers comprise propylene and one or more α-olefin copolymerizable comonomers, characterized by blocks or multiple segments (i.e., two or more) of two or more polymerized monomer units differing in chemical properties or (block interpolymer), preferably a multiblock copolymer. In some embodiments, the multiblock copolymer may be represented by the following formula: (AB) n where n is at least 1, preferably an integer greater than 1, such as 2, 3, 4, 5, 10, 15, 20, 30, 40, 50, 60, 70, 80, 90, 100, or greater; "A" represents a segment or hard block and "B" represents a segment or soft block. Preferably, blocks A and blocks B connect linearly, not in a branched or star shape. "Hard" segments refer to polymerized unit blocks in which propylene is present in an amount greater than 95 weight percent, and preferably greater than 98 weight percent. In other words, the comonomer content in the hard segments is less than 5 weight percent, and preferably less than 2 weight percent. In some embodiments, the hard segments comprise all or substantially all propylene. On the other hand, "soft" segments refer to polymerized unit blocks in which the comonomer content is greater than 5 weight percent, preferably greater than 8 weight percent, greater than 10 weight percent, or greater. 15 percent by weight. In some embodiments, the comonomer content in soft segments may be greater than 20 percent by weight, greater than 25 percent by weight, greater than 30 percent by weight, greater than 35 percent by weight, greater than 40 percent. by weight, greater than 45 percent by weight, greater than 50 percent by weight, or greater than 60 percent by weight.

In some embodiments, blocks A and blocks B are randomly distributed along the polymeric chain. In other words, block copolymers do not have a structure like: AAA — AA-BBB — BB

In other embodiments, block copolymers do not have a third block type. In still other embodiments, each of blocks A and B has monomers or comonomers randomly distributed within the block. In other words, neither block A nor block B comprises two or more segments (or sub-blocks) of distinct composition, such as an end segment, which has a different composition from the rest of the block.

The term "crystalline", if used, shall refer to a polymer having a first order transition or crystalline melting point (Tm) determined by differential scanning calorimetry (DSC) or equivalent technique. The term may be used in a manner that permits exchange or substitution with the term "semicrystalline". The term "amorphous" refers to a polymer not having a crystalline melting point determined by differential scanning calorimetry (DSC) or equivalent technique.

The term "multiblock copolymer" or "segmented copolymer" refers to a polymer comprising two or more chemically distinct regions or segments (referred to as "blocks"), preferably a polymer comprising differentiated units chemically they join end to end with respect to polymerized ethylenic functionality rather than pending or grafted. In a preferred embodiment, the blocks differ in the amount or type of comonomer incorporated into them, the density, the amount of crystallinity, the size of the crystallite attributable to a polymer of such composition, the type or degree of tacticity (isotactic or syndiotactic), regio-regularity or regio-irregularity, in the amount of branching, including long chain branching or hyper-branching, homogeneity, or any other chemical or physical property. Block copolymers are characterized by unique distributions of either polydispersity index (PDI or Mw / Mn), block length distribution and / or block number distribution due to the unique manufacturing process of the copolymers. More specifically, when produced in a continuous process, the polymers desirably have a PDI of 1.7 to 2.9, preferably 1.8 to 2.5, more preferably 1.8 to 2.2, and most preferably 1, 8 to 2.1. When produced in a batch or semi-split process, the polymers have PDIs of 1.0 to 2.9, preferably 1.3 to 2.5, more preferably 1.4 to 2.0, and most preferably 1.4. at 1.8.

In the following description, all numbers disclosed herein are approximate values, regardless of whether used with the term "about" or "approximate" together with it. They can vary by 1 percent, 2 percent, 5 percent, or sometimes 10 to 20 percent. Whenever a numerical range with a lower limit, RL, and an upper limit, Ru is disclosed, any number falling within the range is specifically disclosed. In particular, the following numbers within the range are specifically disclosed: R = RL + k * (RU-RL), where k is a variable ranging from 1 percent to 100 percent with a 1 percent increment, that is , k is 1 percent, 2 percent, 3 percent, 4 percent, 5 percent,. .., 50 percent, 51 percent, 52 percent, ..., 95 percent, 96 percent, 97 percent, 98 percent, 99 percent, or 100 percent. In addition, any numerical range defined by two R numbers as defined above is also specifically disclosed.

Embodiments of the invention provide fibers made from novel propylene / α-olefin interpolymers with unique properties and cloths and other products made from such fibers. The fibers can have good abrasion resistance, low coefficient of friction, high upper service temperature, high recovery / shrink force, low relaxation stress (high and low temperatures), soft stretch, high elongation at break, inert, chemical resistance. , and / or UV resistance. The fibers can be spun fused at a relatively high spin rate and lower temperature. In addition, the fibers are less sticky, resulting in better unwinding performance and better shelf life, and are substantially free of stringing (i.e. fiber bundling). As the fibers can be spun at a higher spin rate, the operational production productivity of the fibers is high. Such fibers also have extensive forming windows and extensive processing windows.

Propylene / α-olefin Interpolymers Propylene / α-olefin interpolymers used in embodiments of the invention (also referred to as "inventive interpolymer" or "inventive polymer") comprise propylene and one or more copolymerizable α-olefin comonomers in polymerized form, are characterized by multiple blocks or segments of two or more polymerized monomer units differing in chemical or physical properties (block interpolymer), preferably a multiple block copolymer. Propylene / α-olefin interpolymers are characterized by one or more of the aspects described below.

In one aspect, the propylene / α-olefin interpolymers have Mw / Mn of from about 1.7 to about 3.5 and at least one melting point, Tm, in degrees Celsius and density, d, in grams. / cubic centimeter (g / cm3), where the numerical values of the variables correspond to the ratios: Tm> -2002, 9 + 4538.5 (d) - 2422.2 (d) 2, and preferably Tm> -6288.1 + 13141 (d) - 6720.3 (d) 2, and more preferably Tm> 858, 91 + 1825, 3 (d) + 1112.8 (d) 2.

Unlike traditional random propylene / α-olefin copolymers whose melting points decrease with decreasing density, inventive interpolymers (represented by diamonds) exhibit substantially density-independent melting points, particularly when the density is between about 0.87 g / cm3 and about 0.95 g / cm3. For example, the melting point of such polymers is in the range from about 110 ° C to about 130 ° C when the density ranges from 0.875 g / cm3 to about 0.945 g / cm3. In some embodiments, the melting point of such polymers is in the range of about 115 ° C to about 125 ° C when the density ranges from 0.875 g / cm3 to about 0.945 g / cm3.

In another aspect, the propylene / α-olefin interpolymers comprise in the polymerized form of propylene and one or more α-olefins and are characterized by a ΔΤ, in degrees Celsius, defined as the temperature for the peak differential calorimetry of highest sweep ("DSC") minus the temperature for the highest crystallization analysis fractional peak ("CRYSTAF"), and a fusion heat at J / g, ΔΗ, and ΔΤ and ΔΗ satisfy the following ratios: ΔΤ> -0.1299 (ΔΗ) + 62.81, and preferably ΔΤ> -0.1299 (ΔΗ) + 64.38, and more preferably ΔΤ> -0.1299 (ΔΗ) + 65.95, for Δη to 130 J / g.

In addition, ΔΤ is greater than or equal to 48 ° C for ΔΗ greater than 130 J / g. The CRYSTAF peak is determined using at least 5 percent of the cumulative polymer (ie, the peak must represent at least 5 percent of the cumulative polymer), and if less than 5 percent of the polymer has an identifiable CRYSTAF peak, then the CRYSTAF temperature will be 30 ° C, and ΔΗ will be the numerical value of the fusion heat in J / g. More preferably, the maximum CRYSTAF peak comprises at least 10 percent of the cumulative polymer.

In another aspect, propylene / α-olefin interpolymers have a molecular fraction that elutes between 40 ° C and 130 ° C when fractionated using temperature elevation elution fractionation ("TREF"), characterized by the fact that said fraction having a higher comonomer molar content, preferably at least 5 percent higher, more preferably at least 10, 15, 20 or 25 percent higher than that of a comparable random propylene interpolymer eluting between the same temperatures, wherein The comparable random propylene interpolymer comprises the same comonomers, and has melt index, density, and comonomer molar content (based on the entire polymer) within 10 percent of that of the block interpolymer. Preferably, the Mw / Mn of the comparable interpolymer is also within 10 percent of that of the block interpolymer and / or the comparable interpolymer has a total comonomer content within 10 percent by weight of that of the block interpolymer.

In yet another aspect, the propylene / α-olefin interpolymers are characterized by a percent elastic recovery, Re, at 300 percent strain and 1 cycle measured on a compression molded film of a propylene / α-olefin interpolymer. , and having a density, d, in grams / cubic centimeter (g / cm3), where the numerical values of Re ed satisfy the following relationship when the propylene / α-olefin interpolymer is substantially free of a cross-linked phase: Re > 1481-1629 (d); and preferably Re 1491-1629 (d); and most preferably Re> 1501-1629 (d); and even more preferably Re 1511-1629 (d).

Compared to traditional random copolymers, the inventive interpolymers have substantially higher elastic recoveries for the same density.

In some embodiments, propylene / α-olefin interpolymers have a tensile strength limit above 10 MPa, preferably a tensile strength limit> 11 MPa, more preferably a tensile strength limit> 13 MPa and an elongation at break of at least 600 per cent, more preferably at least 900 per cent at a crossing separation rate of 11 cm / min.

In other embodiments, the propylene / α-olefin interpolymers have (1) a storage modulus ratio G '(25 ° C) / G' (100 ° C) of 1 to 50, preferably 1 at 20, more preferably from 1 to 10; and / or (2) a compression strain less than 80 percent, preferably less than 70 percent, especially less than 60 percent, less than 50 percent, or less than 40 percent, to a compression strain of 0. Percent.

In some embodiments, propylene / α-olefin interpolymers have a melt heat of less than 85 J / g and / or pellet block resistance less than or equal to 4800 Pa (100 pounds / ft2), preferably less than or equal to at 2400 Pa (50 pounds / ft2), especially less than or equal to 240 Pa (5 pounds / ft2), and as low as 0 Pa (0 pounds / ft2).

In other embodiments, the propylene / α-olefin interpolymers in polymerized form with at least 50 mol percent propylene have a compression strain at 70 ° C less than 80 percent, preferably less than 70 percent or less. than 60 percent, most preferably less than 40 to 50 percent and even close to zero percent.

In some embodiments, multiblock copolymers have PDI corresponding to a Schultz-Flory distribution rather than a Poisson distribution. The copolymers are further characterized by having both a polydisperse block distribution and a polydisperse block size distribution and a highly probable block length distribution. Preferred multiblock copolymers are those containing 4 or more blocks or segments including terminal blocks. More preferably, the copolymers include at least 5, 10 or 20 blocks or segments including terminal blocks.

Comonomer content may be measured using any appropriate technique, with techniques based on nuclear magnetic resonance spectroscopy ("NMR") being preferred. In addition, for polymers or polymer mixtures having relatively wide TREF curves, desirably, the polymer is first fractionated using TREF in fractions each having an eluted temperature range of 10 ° C or less. That is, each eluted fraction has a collection temperature window of 10 ° C or less. Using this technique, said block interpolymers have at least one such fraction having a comonomer molar content greater than that of a corresponding fraction of the comparable interpolymer.

Preferably, for propylene and 1-octene interpolymers, the block interpolymer has a TREF fraction comonomer content eluting between 40 and 130 ° C greater than or equal to the amount (-0.2013) T + 20.07 more preferably greater than or equal to the amount (-0.2013) T + 21.07, where T is the numerical value of the peak elution temperature of the TREF fraction being compared, measured in ° C.

In addition to the properties and aspects described hereinabove, the inventive polymers may be characterized by one or more additional features. In one aspect, the inventive polymer is an olefin interpolymer, preferably comprising propylene and one or more copolymerizable comonomers in polymeric form, characterized by blocks or multiple segments of two or more polymerized monomer units differing in chemical or physical properties (block interpolymer), most preferably a multiblock copolymer, said block interpolymer having a molecular fraction eluting between 40 ° C and 130 ° C, when fractionated using TREF increments, characterized in that said fraction has a larger comonomer molar content, preferably at least 5 percent larger, more preferably at least 10, 15, 20, or 25 percent greater than that of a comparable random propylene interpolymer fraction eluting between the same temperatures, with the comparable random propylene interpolymer having the same comonomers, and a fusion index, density, and content the comonomer molar (based on the entire polymer) within 10 percent of that of the block interpolymer. Preferably, the Mw / Mn of the comparable interpolymer is also within 10 percent of that of the block interpolymer and / or the comparable interpolymer has a total comonomer content within 10 percent of that of the block interpolymer.

Preferably, the above interpolymers are propylene interpolymers and at least one alpha olefin, especially those interpolymers having a total polymer density of about 0.855 to about 0.935 g / cm3, and more especially for polymers having more than about 1 molar percent of comonomer, the block interpolymer has a TREF fraction comonomer content eluting between 40 and 130 ° C greater than or equal to the amount (-0.1356) T + 13.89, more preferably greater than or equal to to the amount (-0.1356) T + 21.07, where T is the numerical value of the TREF elution peak temperature of the TREF fraction being compared, measured in ° C.

Comonomer content can be measured using any appropriate technique, with techniques based on nuclear magnetic resonance spectroscopy ("NMR") being preferred. Further, for polymers or polymer blends having relatively wide TREF curves, desirably, the polymer is first fractionated using TREF in fractions each having an eluted temperature range of 10 ° C or less. That is, each eluted fraction has a collection temperature window of 10 ° C or less. Using this technique, said block interpolymers have at least one such fraction having a comonomer molar content greater than that of a corresponding fraction of the comparable interpolymer.

In another aspect, the inventive polymer is an olefin interpolymer, preferably comprising propylene and one or more copolymerizable comonomers in polymerized form, characterized by multiple blocks or segments of two or more polymerized monomer units differing in chemical or physical properties ( block interpolymer), most preferably a multiblock copolymer, said block interpolymer having a peak (but not exactly a molecular fraction) eluting between 40 ° C and 130 ° C (but without individual isolated and / or collected fractions), characterized in that said peak has an estimated comonomer content by infrared spectroscopy when expanded using a full width / maximum half-area (FWHM) calculation, has a larger average comonomer molar content, preferably 5%. percent larger, more preferably at least 10 percent greater than that of an comparable random propylene at the same elution temperature and expanded using a full width / maximum half-area (FWHM) calculation, said comparable random propylene interpolymer comprising the same comonomers, preferably it is the same comonomer, and has a melt index, density, and comonomer molar content (based on the entire polymer) within 10 percent of that of the block interpolymer. Preferably the Mw / Mn of the comparable interpolymer is also within 10 percent of that of the block interpolymer and / or the comparable interpolymer has a total comonomer content within 10 percent of that of the block interpolymer. The total width / maximum half-area (FWHM) calculation is based on the ATREF infrared detector's methyl to methylene response area ratio [CH3 / CH2], with the highest (maximum) peak being identified from the baseline, and then the FWHM area is determined. For a distribution measured using an ATREF peak, the FWHM area is defined as the area under the curve between Ti and T2, where Ti and T2 are points to the left and right of the ATREF peak by dividing the peak height by two. , and then drawing a horizontal line to the baseline, which intersects the left and right portions of the ATREF curve. Calibration curve for comonomer content is made using random propylene / alpha-olefin copolymers by plotting NMR comonomer content against FWHM area ratio of TREF peak. For this infrared method, the calibration curve is generated for the same type of comonomer of interest. The TREF peak comonomer content of the inventive polymer can be determined by reference to this calibration curve using its TREF peak methyl: methylene FWHM area ratio.

Comonomer content may be measured using any appropriate technique, with techniques based on nuclear magnetic resonance ("NMR") spectroscopy being preferred. Using this technique, said block interpolymers have greater comonomer molar content than that of a corresponding comparable interpolymers.

Preferably, for the above propylene interpolymers and at least one alpha-olefin, especially those interpolymers having a total polymer density of about 0.855 to about 0.935 g / cm3, and more especially for polymers having more that about 1 molar percent comonomer, the block interpolymer has a comonomer content of the TREF fraction eluting between 40 and 130 ° C greater than or equal to the amount (-0,2013) T + 20.07, more preferably greater. or equal to the amount (-2013) T + 21.07, where T is the numerical value of the peak elution temperature of the TREF fraction being compared, measured in ° C.

In yet another aspect, the inventive polymer is an olefin interpolymer, preferably comprising propylene and one or more copolymerizable comonomers in polymerized form, characterized by multiple blocks or segments of two or more polymerized monomer units differing in chemical or other properties. (block interpolimer), most preferably a multiblock copolymer, said block interpolimer having a molecular fraction eluting between 40 ° C and 130 ° C when fractionated using TREF increments, characterized in that every fraction having a Comonomer content of at least about 6 mol percent has a melting point greater than about 10 ° C. For those fractions having a comonomer content of about 3 molar percent to about 6 molar percent, every fraction has a DSC melting point of about 110 ° C or greater. More preferably, said polymer fractions, having at least 1 mol percent comonomer, have a melting point measured by DSC which corresponds to the equation: Tm (- 5.5926) (mol percent percent comonomer in fraction) + 135.90.

In another aspect, the inventive polymer is an olefin interpolymer preferably comprising propylene and one or more copolymerizable comonomers in polymerized form, characterized by multiple blocks or segments of two or more polymerized monomer units differing in chemical or physical properties. (block interpolymer), most preferably a multiblock copolymer, said block interpolymer having a molecular fraction eluting between 40 ° C and 130 ° C when fractionated using TREF increments, characterized in that every fraction having a content which has a worst measured ATREF elution temperature greater than or equal to about 76 ° C, will have a fusion enthalpy (fusion heat) measured by DSC, corresponding to the equation: Melt heat (J / g) <(3, 1718) (ATREF elution temperature in ° C) -136.58.

Interpolymers having a molecular fraction eluting between 40 ° C and 130 ° C when fractionated using TREF increments, characterized in that any fraction having an ATREF elution temperature between 40 ° C and 76 ° C C, has a fusion enthalpy (heat and fusion) as measured by DSC, corresponding to the equation: Melt heat (J / g) δ (1.1312) (ATREF elution temperature in ° C) +22.97.

ATREF Peak Comonomer Composition Measurement by Infrared Detector [0065] TREF peak comonomer composition can be measured using a obtainable IR4 infrared detector from Polymer Char, Valencia, Spain (http://www.polymerchar.com/) .

The detector "compositing mode" is equipped with a measurement sensor (CH2) and compositing sensor (CH3) that fix narrowband infrared filters in the region of 2800-3000 cm-1. The measurement sensor detects the methylene carbons (CH2) in the polymer (which relate directly to the polymer concentration in solution) while the composition sensor detects the methyl (CH3) groups of the polymer. The mathematical ratio of the composition signal (CH3) divided by the measurement signal (CH2) is sensitive to the comonomer content of the polymer measured in solution and its response is calibrated to known propylene / alpha-olefin copolymer standards.

The detector when used with an ATREF instrument provides both a concentration signal response (CH2) and a composition response signal (CH3) of the eluted polymer during the TREF process. A specific polymer calibration can be created by measuring the area ratio of CH3 to CH2 for polymers with known comonomer content (preferably measured by NMR). The comonomer content of an ATREF peak of a polymer can be estimated by applying the reference area ratio calibration to the individual CH3 and CH2 response (ie, CH3 / CH2 area to comonomer content ratio).

Peak area can be calculated using a full width / maximum half area (FWHM) calculation after applying the baselines to integrate the individual TREF chromatogram signal responses. The calculation of full width / maximum half-area is based on the ATREF infrared detector methyl to methylene [CH3 / CH2] response area ratio, with the largest (highest) peak being identified from baseline, and then determine the area of FWHM. For a distribution measured using an ATREF peak, the FWHM area is defined as the area under the curve between Ti and T2, where Ti and T2 are points to the left and right of the ATREF peak, dividing the peak height by two, and then drawing a horizontal line to the baseline, which intersects the left and right portions of the ATREF curve.

The application of infrared spectroscopy to measure polymer comonomer content in this ATREF infrared method is, in principle, similar to that of GPC / FTIR systems described in the following references: Markovich, Ronald P .; Hazlitt, Lonnie G .; Smith, Linley, "Development of gel-permeation chromatography-Fourier transform infrared spectroscopy for characterization of proylene-based polyolefin copolymers", Polymeric Materials Science and Engineering (1991), 65, 98-100; and Deslauriers, P. J .; Rohlfing, D.C .; Shieh, ET, "Quantifying short chain branching microstructures in propylen-1-olefin copolymers using size exclusion chromatography and Fourier transform infrared spectroscopy (SEC-FTIR)", Polymer (2002), 43, 59-170, both of which are incorporated herein. , in its entirety, by reference.

In another aspect, the inventive propylene / α-olefin interpolymer is characterized by an average block index, ABI, which is greater than zero and up to about 1.0 and a molecular weight distribution, Mw / Mn, greater than about 1.3. The average block index, ABI, is the weight average of the block index for each of the polymeric fractions obtained in preparative TREF from 20 ° C to 110 ° C, with an increment of 5 ° C: ABI = Z (WIBI) where BIi is the block index for the ith fraction of the inventive propylene / α-olefin interpolymer obtained from preparative TREF, and wi is the weight percent of the ith fraction.

For each polymeric fraction, BI is defined by one of the following equations (both of which give the same value as BI): where Tx is the preparative ATREF elution temperature for the ith fraction (preferably expressed in Kelvin ), Px is the molar fraction of propylene for the ith fraction, which may be measured by NMR or IR described above. Pab is the molar fraction of the entire propylene / α-olefin interpolymer (before di-fractionation), which can also be measured by NMR or IR. TA and PA are respectively the ATREF elution temperature and the propylene molar fraction for pure "hard segments" (which refers to the crystalline segments of the interpolymer). As a first order approximation, the TA and PA values are adjusted to those for propylene homopolymer if the actual values for the "hard segments" are not obtainable.

Tab is the ATREF temperature for a random copolymer of the same composition and having a propylene molar fraction of Pab · Tab can be calculated using the following equation: lo Pab = <x / Tab + β where α and β are two constants that can be determined by calibration using various random propylene copolymers. Note that α and β may vary from instrument to instrument. In addition, it may be necessary to create your own calibration curve with the polymer composition of interest and also within a molecular weight range similar to those of the fractions. There is a small effect of molecular weight. If the calibration curve is obtained from similar molecular weight ranges, such an effect is essentially negligible. In some embodiments, random propylene copolymers satisfy the following ratio: ln P = —237.83 / Tatref t 0.639 Τχο is the ATREF temperature for a random copolymer of the same composition and having a propylene molar fraction of Px. Τχο can be calculated from ln Px = α / Τχ0 + β. Conversely, Pxo is the propylene molar fraction for a random copolymer of the same composition and having an ATREF temperature of Tx, which can be calculated from ln Pxo = α / Τχ + β.

Once the block index is obtained for each preparative TREF fraction, the weight average block index, ABI, can be calculated for the entire polymer. In some embodiments, ABI is greater than zero but less than about 0.3 or about 0.1 to about 0.3. In other embodiments, ABI is greater than about 0.3 and up to about 1.0. Preferably, ABI should be in the range of from about 0.4 to about 0.7, from about 0.5 to about 0.7, or from about 0.6 to about 0.9. In some embodiments, ABI is in the range of about 0.3 to about 0.9, about 0.3 to about 0.8, or about 0.3 to about 0.7, about from 0.3 to about 0.6, from about 0.3 to about 0.5, or from about 0.3 to about 0.4. In other embodiments, ABI is in the range of about 0.4 to about 1.0, about 0.5 to about 1.0, or about 0.6 to about 1.0, about from 0.7 to about 1.0, from about 0.8 to about 1.0, or from about 0.9 to about 1.0.

Another feature of the inventive propylene / α-olefin interpolymer is that it comprises at least one polymer fraction that can be obtained by preparative TREF, the fraction having a block index of greater than about 0.1 and up to about 100%. about 1.0 and a molecular weight distribution Mw / Mn greater than about 1.3. In some embodiments, the polymer fraction has a block index of greater than about 0.6 and up to about 1.0, greater than about 0.7 and up to about 1.0, greater than about 0.8. and up to about 1.0, or greater than about 0.9 and up to about 1.0. In other embodiments, the polymer fraction has a block index greater than about 0.1 and up to about 1.0, greater than about 0.2 and up to about 1.0, greater than about 0, 3 and up to about 1.0, or greater than about 0.4 and up to about 1.0. In still other embodiments, the polymer fraction has a block index of greater than about 0.1 and up to about 0.5, greater than about 0.2 and up to about 0.5, greater than about 0, 3 and up to about 0.5, or greater than about 0.4 and up to about 0.5. In other embodiments, the polymer fraction has a block index of greater than about 0.2 and up to about 0.9, greater than about 0.3 and up to about 0.8, greater than about 0, 4 and up to about 0.7, or greater than about 0.5 and up to about 0.6.

For propylene and an α-olefin copolymers, the inventive polymers preferably have (1) a PDI of at least 1.3, more preferably at least 1.5, at least 1.7, or at least 2.0, and most preferably from at least 1.6 to a maximum of 5.0, more preferably to a maximum of 3.5, and especially to a maximum of 2.7; (2) a fusion heat of 80 J / g or less; (3) a propylene content of at least 50 percent; (4) a glass transition temperature, Tg, below -25 ° C, more preferably below -30 ° C, and / or (5) one and only one Tm.

In addition, the inventive polymers may have, alone or in combination with any other properties disclosed herein, a storage module, G ', such that log (G') is greater than or equal to 400 kPa, preferably greater than or equal to at 1.0 MPa at a temperature of 100 ° C. Furthermore, the inventive polymers have a relatively flat storage modulus as a temperature function in the range of 0 to 100 ° C which is characteristic of block copolymers, and hitherto unknown for an olefin copolymer, especially a propylene copolymer. and one or more C2 or C4-8 aliphatic α-olefins. (In this context, the term "relatively flat" means that log (G ') (in Pascal) decreases by less than an order of magnitude between 50 and 100 ° C, preferably between 0 and 100 ° C).

The inventive interpolymers may further be characterized by a penetration depth via thermomechanical analysis of 1 mm at a temperature of at least 90 ° C as well as a flexural modulus of 20 MPa (3 kpsi) to 90 MPa (13 kpsi). Alternatively, the inventive interpolymers may have a penetration depth via thermomechanical analysis of 1 mm at a temperature of at least 104 ° C as well as a flexural modulus of at least 20 MPa (3 kpsi). They may be characterized by having an abrasion resistance (or loss of volume) of less than 90 mm3.

Additionally, the interpolymers of the invention may have a melt index, I 2, of from 0.01 to 2000 g / 10 minutes, preferably from 0.01 to 1000 g / 10 minutes, more preferably from 0.01 to 500 g. / 10 minutes, and especially from 0.01 to 100 g / 10 minutes. The polymers may have molecular weights, Mw, from 1,000 g / mol to 5,000,000 g / mol, preferably from 1,000 g / mol to 1,000,000 g / mol, more preferably 10,000 g / mol to 500,000 g / mol, and especially 10,000 g / mol to 300,000 g / mol. The density of the inventive polymers may be from 0.80 to 0.99 g / cm3 and preferably for propylene-containing polymers from 0.85 g / cm3 to 0.97 g / cm3.

The ethylene-based polymer manufacturing process has been disclosed in the following patent applications: U.S. Provisional Patent Application No. 60 / 553,906, filed March 17, 2004; U.S. Patent Application No. 60 / 662,937, filed March 17, 2005; U.S. Patent Application No. 60 / 662,939, filed March 17, 2005; U.S. Patent Application No. 60 / 662,938, filed March 17, 2005; PCT Application No. PCT / US2005 / 008916, filed March 17, 2005; PCT Application No. PCT / US2005 / 008915, filed March 17, 2005; and PCT Application No. PCT / US2005 / 008917, filed March 17, 2005, all of which are incorporated herein by reference in their entirety. The disclosed methods may similarly be used to prepare propylene based polymers with or without modifications. For example, such a method comprises contacting propylene and optionally one or more addition polymerizable monomers other than propylene under addition polymerization conditions with a catalyst composition comprising: the reaction mixture or product resulting from combining: (A) a first olefin polymerization catalyst having a high comonomer incorporation index, (B) a second olefin polymerization catalyst having a comonomer incorporation index of less than 90 percent, preferably less than 50 percent, most preferably less than 5 percent. percent catalyst incorporation index (A), and (C) a chain transfer (or transfer) agent.

Chain transfer agent and representative catalysts are below.

Catalyst (Al) is dimethyl [N- (2,6-di (1-methyl-ethyl) phenyl) amido) (2-isopropyl-phenyl) (α-naphthalen-2-diyl) methane) hafnium prepared according to the teachings of WO 03/40195, 2003 US 0204017, USNN 10 / 429,024, filed May 2, 2003, and WO 04/24740.

Catalyst (A2) is dimethyl [N- (2,2-di (1-methylethyl) phenyl) starch) (2-methylphenyl) (1,2-phenylene-6-pyridin-2-diyl] ) methane) hafnium, prepared according to the teachings of WO 03/40195, 2003 US 0204017, USNN 10 / 429,024, filed May 2, 2003, and WO 04/24740.

Catalyst (A3) is dibenzyl bis [N, N '' '- (2,4,6-tri (methylphenyl) starch) ethylenediamine] hafnium.

Catalyst (A4) is dibenzyl bis ((2-oxoyl-3- (dibenzo-1H-pyrrol-1-yl) -5- (methyl) phenyl) -2-phenoxymethyl) cyclohexane-1, 2-diyl zirconium (IV), prepared substantially in accordance with the teachings of US-A-2004/0010103.

Catalyst (B1) is dibenzyl 1,2-bis- (3,5-dimethylbutylene) (1- (N- (1-methyl-ethyl) imino) methyl) (2-oxoyl) zirconium Catalyst (B2) is dibenzyl 1,2-bis- (3,5-di-tertiary butylphenylene) (1- (N- (2-methylcyclohexyl) imino) methyl) (2-oxoyl) zirconium [0085] Catalyst (Cl) is dimethyl (tert-butylamido) dimethyl (3-N-pyrrolyl-1,2,3,3a, 7α-β-inden-1-yl) silane titanium prepared substantially according to the techniques of USP 6,268,444 Catalyst (C2) is dimethyl (tertiary butylamido) di (4-methyl-phenyl) (2-methyl-1,2,3,3a, 7α-β-inden-1-yl) silane prepared substantially from According to the teachings of US-A-20 03/00428 6: Catalyst (C3) is dimethyl (tertiary butylamido) di (4-methylphenyl) (2-methyl-1,2,3,3a, 8a titanium -ri-s-indacen-1-yl) silane prepared substantially according to the teachings of US-A-2003/004286: Catalyst (D1) is bis (dimethyl disiloxane) dichloride (indene 1-yl) Obtainable Sigma-Aldrich Zirconium: Carriers 89] Carriers employed include diethyl zinc, di (isobutyl) zinc, di (n-hexyl) zinc, triethyl aluminum, trioctyl aluminum, triethyl gallium, isobutyl aluminum bis (dimethyl (tertiary butyl) siloxane), isobutyl aluminum bis (di (trimethylsilyl) amide), n-octyl aluminum di (pyridine-2-methoxide), bis (n-octadecyl) isobutyl aluminum, isobutyl aluminum bis (di (n-pentyl) amide), n-octyl aluminum bis (2,6-ditherciobutyl phenoxide), n-octyl aluminum di (ethyl (1-naphthyl) amide), ethyl aluminum bis (tertiary butyl dimethyl siloxide), ethyl aluminum di (bis (trimethylsilyl) amide), ethyl aluminum bis (2,3,6,7-dibenzo-1-aza-cycloheptanamide), n-octyl aluminum bis (2,3,6,7-dibenzo-1-aza-cycloheptanamide), n-octyl octyl aluminum bis (dimethyl (tertiary butyl) siloxide, ethyl zinc (2,6-diphenylphenoxide), and ethyl zinc tertiary butoxy.

Preferably, the above process takes the form of a continuous solution process to form block copolymers, especially multiblock copolymers, preferably linear multiblock copolymers of two or more monomers, more especially C2 or C4-20 propylene and olefin. or cycloolefin, and most especially C4-20 propylene and α-olefin using multiple catalysts that are incapable of interconversion. That is, the catalysts are chemically distinct. Under continuous solution polymerization conditions, the process is ideally suited for polymerization of monomer mixtures at high monomer conversions. Under these polymerization conditions, transport of the chain transport agent to the catalyst becomes advantageous compared to chain growth, and multiblock copolymers, especially linear multiblock copolymers are formed with high efficiency.

Inventive interpolymers can be differentiated from conventional random copolymers, physical polymer mixtures, and block copolymers prepared via sequential monomer addition, catalysts subject to constant modification, cationic or anionic living polymerization techniques. In particular, compared to a random copolymer of the same monomers and monomer content in modulus or equivalent crystallinity, the inventive interpolymers have better (higher) melt-point heat resistance, higher TMA penetration temperature, higher tensile strength limit. at high temperature, and / or larger high temperature torsion storage module determined by dynamic mechanical analysis. Compared to a random copolymer comprising the same monomers and monomer content, the inventive interpolymers have lower compression adjustment, particularly at elevated temperatures, lower stress relaxation, higher creep resistance, higher tear strength, higher blocking resistance, arrangement. Faster due to higher crystallization (solidification) temperature, higher recovery (particularly at elevated temperatures), better abrasion resistance, higher shrinkage force, and better oil and load acceptance.

The inventive interpolymers also exhibit unique branching and crystallization distribution ratios. That is, the inventive interpolymers have a relatively large difference between the maximum peak temperature measured using CRYSTAF and DSC as a melt heat function, especially when compared to random copolymers comprising the same monomer and monomer level or physical polymer mixtures, such as a mixture of a high density polymer and a lower density copolymer at equivalent global density. This unique feature of the inventive interpolymers is believed to be due to the unique distribution of the block comonomer within the polymer backbone. In particular, the inventive interpolymers may comprise alternate blocks of different comonomer content (including homopolymer blocks). The inventive interpolymers may also comprise a block number and / or block size distribution of different comonomer content or density polymer, which is a Schultz-Flory distribution type. In addition, the inventive interpolymers also have a single peak melting point and single crystallization temperature profile that is substantially independent of polymer density, modulus, and morphology. In a preferred embodiment, the microcrystalline order of the polymers demonstrates characteristic lamellas and spherulites that are distinguishable from block or random copolymers, even at PDI values that are less than 1.7, or even less than 1.5, decreasing to less than that 1.3.

In addition, inventive interpolymers may be prepared using techniques to influence the degree or level of blockage. That is, the amount of comonomer and the length of each polymer block or segment can be changed by controlling the ratio and type of catalysts and carrier as well as the polymerization temperature and other polymerization variables. A surprising benefit of this phenomenon is the discovery that when the degree of blockage increases, optical properties, tear strength, and high temperature recovery properties improve. In particular, fog decreases while clarity, tear strength, and high temperature recovery properties increase as the average number of blocks increases in the polymer. Selecting transfer agents and catalyst combinations having the desired ability to chain transfer (high transfer rates with low levels of chain termination) effectively eliminates other forms of polymer termination. Therefore, there is little, perhaps no elimination of β-hydride in the polymerization of propylene / α-olefin comonomer mixtures according to embodiments of the invention, and the resulting crystalline blocks are very, or substantially completely linear, having listen or no long chain branch.

Polymers with very crystalline chain ends may be selectively prepared according to embodiments of the invention. In elastomer applications, reducing the relative amount of polymer that ends with an amorphous block reduces the intermolecular dilution effect in crystalline regions. This result can be obtained by choosing chain transfer agents and catalysts having an appropriate response to hydrogen or other chain terminating agents. Specifically, if the catalyst that produces very crystalline polymer is more susceptible to chain termination (eg using hydrogen) than the catalyst responsible for producing the less crystalline polymer segment (eg through greater comonomer incorporation, higher regimen). error, or greater formation of atomic polymer), then the very crystalline polymer segments will preferably populate the terminal portions of the polymer. Not only will the resulting end groups be crystalline, but in response to termination, the very crystalline polymer-forming catalyst site will again be available to restart polymer formation. The initially formed polymer is therefore another very crystalline polymer segment. Accordingly, both ends of the resulting multiblock copolymer are preferably very crystalline.

Propylene / α-olefin interpolymers used in the embodiments of the invention are preferably propylene interpolymers with at least one C2 or C4-C20 α-olefin. Propylene copolymers with an α-olefin are especially preferred. C2-C20 or C4 -C20 Interpolymers may further comprise C4-C18 diolefins and / or alkenylbenzenes. Suitable unsaturated comonomers useful for polymerization with propylene include, for example, ethylenically unsaturated monomers, conjugated and unconjugated dienes, polyenes, alkenylbenzenes, etc. Examples of such comonomers include C 2 or C 4 -C 20 α-olefins such as propylene, isobutylene, 1-butene, 1-hexene, 1-pentene, 4-methyl-1-pentene, 1-heptene, 1-octene, 1 -nonene, 1-decene, and the like. Especially preferred are 1-butene and 1-octene. Other suitable monomers include styrene, halogen or alkyl substituted styrenes, vinyl benzo-cyclobutane, 1,4-hexadiene, 1,7-octadiene, and naphthenics (e.g., cyclopentene, cyclohexene and cycloocten).

While propylene / α-olefin interpolymers are preferred polymers, other propylene / olefin polymers may also be used. "Olefins" as used herein refer to a family of unsaturated hydrocarbon-based compounds with at least one carbon-carbon double bond. Depending on the selection of catalysts, any olefin may be used in embodiments of the invention.

Preferably, suitable olefins are aliphatic or aromatic C2 or C4-C20 compounds containing vinyl unsaturation, as well as cyclic compounds such as cyclobutene, cyclopentene, di-cyclopentadiene, and norbornene, including but not limited to substituted norbornene at positions 5 and 6 with C 12-20 hydrocarbyl or cyclohydrocarbyl groups Also included are mixtures of such olefins as well as mixtures of such olefins with C 4 -C 40 diolefin compounds.

Examples of olefinic monomers include, but are not limited to, propylene, isobutylene, 1-butene, 1-pentene, 1-hexene, 1-heptene, 1-octene, 1-nonene, 1-decene, and 1-dodecene 1-tetradecene, 1-hexadecene, 1-octadecene, 1-eicosene, 3-methyl-1-butene, 3-methyl-1-pentene, 4-methyl-1-pentene, 4,6-dimethyl-1-heptene , 4-vinyl cyclohexene, vinyl cyclohexene, norbornadiene, ethylidene norbornene, cyclopentene, cyclohexene, di-cyclopentadiene, cyclooctene, C4-40 dienes, including but not limited to 1.3 -butadiene, 1,3-pentadiene, 1,4-hexadiene, 1,5-hexadiene, 1,7-octadiene, 1,9-decadiene, other C 4-40 α-olefins, and the like. While any hydrocarbon containing a vinyl group can potentially be used in embodiments of the invention, practical issues such as monomer availability, cost, and ability to conveniently remove unreacted monomer from the resulting polymer may become more complex. problematic when the molecular weight of the monomer becomes too high.

The polymerization processes described herein are well suited for the production of olefinic polymers comprising monovinylidene aromatic monomers including styrene, o-methyl styrene, p-methyl styrene, tertiary butyl styrene, and the like. In particular, interpolymers comprising propylene and styrene may be prepared by following the teachings shown herein. Optionally, copolymers comprising ethylene, styrene and a C4-20 alpha olefin, optionally comprising a C4-20 diene having improved properties may be prepared.

Suitable unconjugated diene monomers may be a normal chain, branched chain or cyclic hydrocarbon diene having from 6 to 15 carbon atoms. Examples of unconjugated dienes include, but are not limited to, normal chain acyclic dienes such as 1,4-hexadiene, 1,6-octadiene, 1,7-octadiene, 1,9-decadiene, branched chain acyclic dienes, such as 5-methyl-1,4-hexadiene, 3,7-dimethyl-1,6-octadiene, 3,7-dimethyl-1,7-octadiene and isometric mixtures of dihydromyricene and dihydroocinene, dienes single-ring alicyclics such as 1,3-cyclopentadiene, 1,4-cyclohexadiene, 1,5-cyclooctadiene and 1,5-cyclododecadiene, and fused or bridged multi-ring alicyclic dienes such as as tetrahydroindene, methyl tetrahydroindene, di-cyclopentadiene, bicyclo- (2,2,1) -hepta-2,5-diene; alkenyl, alkylidene, cycloalkenyl and cycloalkylidene norbornenes, such as 5-methylene-2-norbornene (MNB), 5-propenyl-2-norbornene, 5-isopropylidene-2-norbornene, 5- (4-cyclopentenyl) -2-norbornene, 5-cyclohexylidene-2-norbornene, 5-vinyl-2-norbornene, and norbornadiene. Of the dienes typically used to prepare EPDMs, particularly preferred dienes are 1,4-hexadiene (HD), 5-ethylidene-2-norbornene (ENB), 5-vinylidene-2-norbornene (VNB), 5-methylene-2- norbornene (MNB), and di-cyclopentadiene (DCPD). Especially preferred dienes are 5-ethylidene-2-norbornene (ENB) and 1,4-hexadiene (HD).

One class of desirable polymers that can be prepared according to embodiments of the invention are elastomeric interpolymers of propylene, a C2 or C4-C20 α-olefin, especially ethylene, and optionally one or more diene monomers. Preferred α-olefins for use in this embodiment of the present invention are designated by the formula CH 2 = CHR *, where R is a straight or branched alkyl group of 1 to 12 carbon atoms. Examples of suitable α-olefins include, but are not limited to, propylene, isobutylene, 1-butene, 1-pentene, 1-hexene, 4-methyl-1-pentene, and 1-octene. A particularly preferred α-olefin is propylene. Propylene based polymers are generally referred to in the art as EP or EPDM polymers. Suitable dienes for use in the preparation of such polymers, especially multiblock EPDM-type polymers include cyclic or polycyclic, straight chain or branched, conjugated or unconjugated dienes containing from 4 to 20 carbon atoms. Preferred dienes include 1,4-pentadiene, 1,4-hexadiene, 5-ethylidene-2-norbornene, di-cyclopentadiene, cyclohexadiene, and 5-butylidene-2-norbornene. A particularly preferred diene is 5-ethylidene-2-norbornene.

Since diene-containing polymers contain alternating blocks or segments containing greater or lesser amounts of diene (including no amount) and α-olefin (including no amount), the total amount of diene and α-olefin can be reduced without loss. of subsequent polymeric properties. That is, since diene and α-olefin monomers preferably incorporate into a polymer block type rather than uniformly or randomly throughout the polymer, they are more efficiently used and subsequently the crosslinking density can be better controlled. Such crosslinkable elastomers and cured products have advantageous properties, including higher tensile strength limit and better elastic recovery.

In some embodiments, the inventive interpolymers prepared with two catalysts incorporating different amounts of comonomer have a weight ratio of blocks thus formed from 95: 5 to 5:95. Desirably, elastomeric polymers have a propylene content of 20 to 90 percent, a diene content of 0.1 to 10 percent, and an α-olefin content of 10 to 80 percent based on total polymer weight. . Even more preferably, multiblock elastomeric polymers have a propylene content of 60 to 90 percent, a diene content of 0.1 to 10 percent, and an α-olefin content of 10 to 90 percent based on weight. polymer total. Preferred polymers are high molecular weight polymers having a weight average molecular weight (Mw) of from 10,000 to about 2,500,000, preferably from 20,000 to 500,000, more preferably from 20,000 to 350,000, and a polydispersity of less than 3,5, more preferably less than 3.0, and a Mooney viscosity [ML (1 + 4) 125 ° C] of 1 to 250. More preferably, such polymers have a propylene content of 65 to 75 percent, a diene content of 0 to 6 percent, and an α-olefin content of 20 to 35 percent.

Propylene / α-olefin interpolymers may be functionalized by incorporating at least one functional group into their polymeric structure. Exemplary functional groups may include, for example, ethylenically unsaturated mono and difunctional carboxylic acids, salts thereof and esters thereof. Such functional groups may be grafted to a propylene / α-olefin interpolymer, or may be copolymerized with propylene and an optional additional comonomer to form a propylene interpolymer, functional comonomer and optionally other comonomers. Means for grafting polyethylene functional groups to U.S. Patent Nos. 4,762,890, 4,927,888, and 4,950,541 are hereby incorporated by reference in their entirety. A particularly useful functional group is maleic anhydride.

[0104] The amount of the functional group present in the functional interpolymer may vary. Typically, the functional group may be present in a copolymer-type functionalized interpolymer in an amount of at least about 1.0 weight percent, preferably at least about 5 weight percent, and more preferably at least about 7 weight percent. percent by weight. Typically, the functional group will be present in a copolymer-type functionalized interpolymer in an amount of less than about 40 weight percent, preferably less than about 30 weight percent, and more preferably less than about 25 weight percent.

Fibers and articles of manufacture The preferred use of inventive fibers is in the formation of cloths, especially non-woven cloths. Cloths formed from the fibers have been shown to have excellent elastic properties making them suitable for many garment applications. They also have good trim.

Some of the desirable properties of fibers and cloths may be expressed in terms of tensile modulus and permanent deformation. For heat-welded cloths according to the invention, the following properties are obtained: [0107] Traction module (g) (ASTM-1682) (100% extension, 6 cycles, machine direction (MD)): preferably less than 900, more preferably less than 800, most preferably from 100 to 400; and / or Tensile modulus (g) (50% extension, 6 cycles, MD): preferably less than 700, more preferably less than 600, most preferably from 100 to 300; and / or Traction modulus (g) (100% length, 6 cycles, transverse direction (TD)): preferably less than 600, more preferably less than 500, most preferably from 50 to 300; and / or tensile modulus (g) (50% extension, 6 cycles, TD): preferably less than 370, more preferably 40 to 200; and / or [0111] Permanent deformation (%) (obtained by using an ASTM D-1682 modification in which stretching is in cycles rather than continuous through cloth failure) (50% extension, 6 cycles, MD): preferably less than 30, more preferably in the range from about 5 to about 25%, most preferably less than 10-20; and / or Permanent deformation (%) (50% extension, 6 cycles, TD): preferably less than 35%, more preferably in the range of about 5 to about 25%; and / or Permanent deformation (%) (100% extension, 6 cycles, MD): preferably less than 40%, more preferably in the range from about 5 to about 35%, most preferably from 8-20%. ; and / or Permanent deformation (%) (100% extension, 6 cycles, TD): preferably less than 40%, more preferably in the range from about 5 to about 35%, most preferably from 5-25%. ; and / or Binding temperature (° C) of less than 110, more preferably in the range from about 35 to about 105, most preferably from 40-80. These properties are preferred and useful for all cloths of the invention, and are demonstrated, for example, by a cloth made from fibers according to the invention and having a basis weight of about 70 to about 80 g / kg. m2, preferably about 70 g / m2 and formed of fibers having a diameter of about 25-28 μιη.

For melted expanded cloth according to the invention, the preferred properties are as follows: Permanent deformation (%) (50% extension, 6 cycles, MD): preferably less than 25, more preferably in range from about 10 to about 20, most preferably from 15-18; and / or Permanent deformation (%) (50% extension, 6 cycles, TD): preferably less than 25, more preferably in the range from about 10 to about 20, most preferably from 15-18; and / or Traction module (g) (50% extension, 6 cycles, MD): preferably no more than about 300, more preferably in the range of about 200 to about 300; and / or Tensile modulus (g) (50% extension, 6 cycles, TD): preferably less than about 300, more preferably in the range of about 50 to about 150; and / or Total tactile quality (g): preferably less than 75, more preferably less than about 70, most preferably in the range of about 10 to about 20.

These properties are preferred and useful for all cloths of the invention, and are demonstrated, for example, by expanded melt cloth with a nominal basis weight of about 70 g / m2 according to the invention, made of fibers according to the invention 8-10 prn in diameter.

Various homogeneous filament fibers produced from the copolymer of the present invention, including short fibers, heat-welded fibers or melt-expanded fibers (using, for example, systems such as those disclosed in USP 4,340,563, 4,663,220, 4,668 .566 or 4,322,027), and gel spun fibers (e.g., the system disclosed in USP 4,413,110). Short fibers may be heat-welded directly to the final fiber diameter without further stretching, or they may be heat-welded to a larger diameter and subsequently hot or cold drawn to the desired diameter using conventional fiber stretching techniques.

Two-component fibers may also be produced from the copolymers of this invention. Such two-component fibers have the copolymer of the present invention in at least a portion of the fiber. For example, in a two component shell / core type fiber (i.e. a fiber in which the shell concentrically surrounds the core), the polyolefin may be either the shell or the core.

Typically and preferably, the copolymer is the shell component of the two-component fiber, but if it is the core component, then the shell component should be such that it does not prevent core crosslinking, that is, the shell component is translucent or transparent to UV radiation such that sufficient UV radiation passes therethrough to substantially crosslink the core polymer. Different copolymers may also be used independently as a shell and as a core in the same fiber, preferably where both components are elastic and especially where the shell component has a lower melting point than the core component. Other types of two-component fiber are also within the scope, and include structures such as side-by-side conjugated fibers (e.g., fibers having separate polymer regions, wherein the polyolefin of the present invention comprises at least a portion of the surface. fiber).

[0125] The shape of the fiber is not limited. For example, the typical fiber has a circular cross-sectional shape, but sometimes the fibers have different shapes, such as a trilobed shape, or a flat shape (that is, as a "ribbon"). The fiber disclosed herein is not limited by the shape of the fiber.

[0126] Fiber diameter can be measured and reported in various ways. Generally, denier fiber diameter is measured by filament. Denier is a textile term defined as grams of fiber per 9000 meters in length of that fiber. Monofilament generally refers to an extruded course having a filament denier greater than 15, usually greater than 30. Thin fiber denier refers to a fiber having a denier of about 15 or less. Microdenier (also known as microfiber) generally refers to a fiber having a diameter no larger than about 100 micrometers. For the fibers of this invention, the diameter may vary widely, with little impact on fiber elasticity. However, the fiber denier may be adjusted to fit well with the capabilities of the finished article and as such will preferably be: from about 0.5 to about 30 denier / filament for expanded melt fibers; from about 1 to about 30 denier / filament for heat-sealed fibers; and from about 1 to about 20,000 denier / filament for continuous wound filament. Preferably, however, the denier is greater than 40, more preferably greater than or equal to 55, and most preferably greater than or equal to 65. These preferences are due to the fact that durable clothing typically employ fibers with denier greater than about 40. .

The elastic copolymer may also be molded or made into films, coatings, sheets, strips, tapes, elastic bands and the like. Elastic films, coatings or sheets of the present invention may be manufactured by any method known in the art, including expanded bubble processes (e.g. single bubble as well as biaxial orientation techniques such as trapped bubble, double bubble and cloth extending frame) , cast extrusion, injection molding processes, thermoforming molding processes, and sheet extrusion processes. Single expanded bubble film processes are described, for example, in "The Encyclopedia of Chemical Technology", Kirk-Othmer, Third Edition, John Wiley & Sons, New York, 1981, vol. 16, pages 416-417 and vol. 18, pages 191-192. The melt extrusion method is described, for example, in "Modern Plastics Mid-October 1989 Encyclopedia Issue", volume 66, number 11, pages 256 to 257. Injection molding, thermoforming molding, extrusion coating, extrusion processes profile, and sheet extrusion are described, for example, in "Plastics Materials and Processes", Seymour S. Schwartz and Sidney H. Goodman, Van Nostrand Reinhold Company, New York, 1982, pages 527-563, pages 632-647 , and pages 596-602.

The strips, tapes and elastic bands of the present invention may be prepared by any known method, including the direct extrusion process or by post-extrusion cracking, cutting or stamping techniques. Profile extrusion is an example of a primary extrusion process that is particularly suitable for preparing tapes, strips, strips and the like.

The fiber can be used with other fibers such as PET, nylon, KEVLAR ™, etc., to make elastic cloths. As an added advantage, the heat (and moisture) resistance of certain fibers may allow polyester / PET fibers to be dyed under common dyeing conditions. Other commonly used fibers, especially spandex (eg LYCRA ™), can only be used under less severe PET dyeing conditions to prevent property degradation.

The cloths made of the fibers of this invention include woven, non-woven and knitted cloths. Nonwoven cloths may be made by various methods, for example, hydrodynamically entangled spun as disclosed in USP 3,485,706 and 4,939,016, carded thermally bonded short fibers; thermosolded continuous fibers in a continuous operation; or by melt-expanding fibers in a cloth and subsequently calendering or thermally bonding the resulting mesh. These various nonwoven cloth manufacturing techniques are well known to those skilled in the art and the disclosure is not limited to any particular method. Other structures made of such fibers also fall within the scope of the invention, including, for example, blending these new fibers with other fibers (e.g. poly (ethylene terephthalate) or cotton).

Nonwoven cloths may be of fibers obtained from solution spinning or flash spinning of the inventive ethylene / α-olefin interpolymers. Solution wiring includes wet wiring and dry wiring. In both methods, a slimy polymer solution is pumped through a filter and then passed through the thin holes of a spinneret. Subsequently, the solvent is removed, leaving a fiber.

In some embodiments, the following process is used for flash-spun fibers and sheets formed from an inventive ethylene / α-olefin interpolymer. The basic system was previously disclosed in U.S. Patent Nos. 3,860,369 and 6,117,801, which are incorporated herein in their entirety by reference. The process is performed in a chamber sometimes referred to as a yarn cell, which has a steam removal hole and an opening through which the produced nonwoven sheet material is removed. The polymer (or liquid strand) solution is prepared continuously or by batch at elevated temperature and pressure and provided to the strand cell via a conduit. The solution pressure is greater than the cloud point pressure which is the lowest pressure at which the polymer completely dissolves in the spinning agent forming a single phase homogeneous mixture.

[0133] The single-phase polymer solution passes through a descent hole in a smaller (or reduced) pressure chamber. In the smaller pressure chamber, the solution separates into a biphasic liquid-liquid dispersion. One dispersion phase is a spinning agent rich phase comprising mainly the spinning agent and the other dispersing phase is a polymer rich phase containing most of the polymer. This liquid-liquid biphasic dispersion is forced through a spinneret into a much lower pressure area (preferably atmospheric pressure) where the spinning agent evaporates very quickly (flashes), and the polymer emerges from the spinneret as a wire (or plexifilation). The wire is stretched in a tunnel and directed to press rotational baffle. The rotating baffle has a shape that transforms the wire into a flat net, which is about 5-15 cm wide, and separates the fibrils to break up the net. The rotating baffle further provides forward and backward oscillatory motion having sufficient amplitude to generate a wide range back and forth. The net is lowered on a moving wire belt about 50 cm below the spinner, and the oscillating forward and backward movement is arranged to be generally transverse to the belt to form a sheet.

[0134] When the screen is deflected by the baffle from its path to the moving drive belt, it enters a crown loading zone between a stationary multi-tipped ion gun and grounded rotary target plate. The multi-tipped ion gun is charged to a potential DC by an appropriate voltage source. The charged screen is carried by a high speed spinning vapor stream through a diffuser consisting of two parts: a front section and a rear section. The diffuser controls the screen expansion and reduces it. The rear section of the diffuser can be stationary and separate from the target plate, or it can be integrated with it. In the case where the rear section and the target plate are integrated, they rotate together. Suction holes are drilled in the rear section of the diffuser to ensure adequate gas flow between the moving screen and the rear section of the diffuser to prevent moving mesh from adhering to the rear section of the diffuser. The moving belt is grounded through cylinders so that the charged net is electrostatically attracted to the belt and held in place in it. Overlapping web strips collected over the drive belt and thus maintained by electrostatic forces are formed into a sheet with a thickness controlled by the speed of the drive belt. The sheet is compressed between the belt and the consolidation cylinder in a frame having sufficient strength to be handled outside the chamber and then collected outside the chamber in a winding cylinder.

Therefore, some embodiments of the invention provide a flash-spun plexifilament material comprising an inventive ethylene / α-olefin interpolymer described herein. Preferably, the ethylene / α-olefin interpolymer has a melt index of from about 0.1 to about 50 g / 10 min or from about 0.4 to about 10 g / 10 min and a density of about 0.85 to about 0.95 g / cm3 or about 0.87 to about 0.90 g / cm3. Preferably, the molecular weight distribution of the interpolymer is greater than about 1 but less than about four. In addition, the flash-spun plexifilament material has a BET surface area of greater than about 2 m 2 / g or greater than about 8 m 2 / g. A flash-spun nonwoven sheet material can be made from soft polymeric flash-spun plexifilament material. The soft flash spun nonwoven sheet material can be heat sealed, area bonded, or spot bonded. Other embodiments of the invention provide soft polymeric flash-spun plexifilament material comprising an ethylene / α-olefin interpolymer (described herein) mixed with high density polyethylene polymer, wherein the ethylene / α-olefin interpolymer has a melt index between about 0.4 to about 10 g / 10 min, a density between about 0.87 and about 0.93 g / cm3, and a molecular weight distribution of less than about 4, and of which the plexifiable material is It has a BET surface area greater than about 8 m2 / g. The flash-spun nonwoven sheet has an opacity of at least 85%.

Flash spunbonded nonwoven sheets produced by a process similar to the above process can be used to replace Tyvek® heat-sealed olefin sheets for air infiltration barriers in construction applications such as packaging such as air express envelopes, as medical packaging, as banners, and for protective clothing and other uses.

Manufactured articles that can be produced using the fibers and cloths of this invention include elastic composite articles (e.g., diapers) having elastic portions. For example, elastic portions are typically constructed and diaper strap band portions to prevent the diaper from falling out and leg band portions to prevent leakage (as shown in USP 4,381,781 (Sciaraffa), the disclosure of which is incorporated herein by reference). Frequently, elastic portions facilitate better fit and / or fastening systems for a good combination of comfort and reliability. Inventive fibers and cloths also produce structures that combine elasticity with breathability. For example, inventive fibers, rags and / or films may be incorporated into the structures disclosed in provisional patent application US 60 / 083,784, filed May 1, 1998. Nonwoven laminates comprising fibers of the invention may also be formed and may be formed. Used in various articles including consumer products such as durable and disposable consumer products such as clothes, diapers, hospital gowns, hygiene applications, upholstery cloths, etc.

Inventive fibers, films and cloths may also be used in various structures described in USP 2,957,512. For example, a layer 50 of the structure described in USP 2,957,512 (i.e. the elastic component) may be replaced by inventive cloths and fibers, especially where flat, folded, crepe-shaped, pleated, etc. materials are non-elastic. are transformed into elastic structures. The attachment of inventive fibers and / or cloths to non-fibers, cloths or other structures may be by heat sealing or with adhesives. Pleated or puckered elastic structures can be made from inventive fibers and / or cloths and non-elastic components by pleating non-elastic components (described in USP 2,957,512) prior to attachment, pre-stretching the elastic member before attachment or thermally shrinkage. the elastic component after fixation.

Inventive fibers can also be used in a spunbond (hydrodynamically entangled) process to produce new structures. For example, USP 4,801,482 discloses an elastic sheet (12) which can now be prepared with the novel fibers / films / cloths described herein.

Continuous elastic filaments described herein may also be used in nonwoven or knitted applications where high elasticity is desired.

[0141] USP 5,037,416 describes the advantages of shape-fitting topsheet using elastic tapes (see member 19 of USP 5,037,416). The inventive fibers could benefit from the limb function 19 of USP 5,037,416, or could be used in cloth form to provide the desired elasticity.

In U.S. Patent No. 4,981,747 (Morman), the inventive fibers and / or cloths disclosed herein may be replaced by elastic sheet 122, which forms a composite elastic material including a reversibly stretched material.

The inventive fibers may also be a melt expanded elastic component as described in reference 6 of US Patent Specification No. 4,879,170 (Radwanski) which generally describes elastic co-formed material and processes of manufacturing.

Elastic panels may also be made from the inventive fibers and cloths disclosed herein, and may be used, for example, as members 18, 20, 14, and / or 26 of U.S. Patent No. 4,490,464. The inventive fibers and cloths described herein may also be used as elastic components of composite side panels (e.g. USP'464 layer 86).

The elastic materials of the present invention may also become permeable or "breathable" by any method known in the art including opening, cracking, micro-drilling, blending with fibers or foams, or the like and combinations thereof. Examples of such methods include U.S. Patent No. 3,156,242 to Crowe, Jr., U.S. Patent No. 3,881,489 to Hartwell, U.S. Patent No. 3,989,867 to Sisson and U.S. Patent No. 5,085,654 to Buell.

The fibers according to certain embodiments of the invention may be covered fibers. Covered fibers comprise a core and a cover. For the purposes of this invention, the core comprises one or more elastic fibers, and the cover comprises one or more inelastic fibers. At the time of construction of the covered fiber and in its respective undrawn state, the covering is longer, typically significantly longer than the core fiber. The cover surrounds the core in a conventional manner, typically in a spiral shell configuration. Bare fibers are fibers without a covering. For the purposes of this invention, a braided fiber or yarn, i.e. a fiber consisting of two or more filaments or threads (elastic and / or inelastic) of approximately equal length in their respective unstretched states intertwined with or twisted together , is not a covered fiber. These yarns can, however, be used as both a core and a covering of the covered fiber. For the purposes of this invention, fibers consisting of an elastic core wrapped in an elastic covering are not covered fibers.

Complete or substantial reversibility of thermally adjustable stretch imparted to a fiber or cloth made of the fiber may be a useful property. For example, if a covered fiber can be thermally adjusted prior to dyeing and / or weaving, then dyeing and / or weaving processes will be more efficient because the fiber is less likely to stretch during winding operations. This, in turn, may be useful in dyeing and weaving operations in which the fiber is first wound over a spool. Once the dyeing and / or weaving is completed, then the covered fiber or cloth comprising the covered fiber may be relaxed. Not only will this technique reduce the amount of fiber required for a particular weaving operation, but it will also protect against subsequent shrinkage. Such reversible thermally adjustable elastic fibers, and methods for manufacturing the fibers and articles made from such fibers are disclosed in US serial application No. 10 / 507,230 (published as US 200550165193), which is incorporated herein by reference in its entirety. . Such methods may also be used in embodiments of the invention with or without modifications to produce cloths, reversible thermally adjustable elastic fibers and articles made therewith.

Pre-activated articles may be made in accordance with the teachings of U.S. Patent Nos. 5,226,992, 4,981,747 (KCC, Morman), and 5,354,597, all of which are incorporated herein by reference in their entirety. .

High tenacity fibers may be made according to the teachings in U.S. Patent Nos. 6,113,656, 5,846,654, and 5,840,234, all of which are incorporated herein by reference in their entirety.

Low denier fibers, including microdenier fibers, can be produced with the inventive interpolymers.

Mixing with Another Polymer Propylene / α-olefin interpolymers may be mixed with at least one other polymer to produce fibers such as polyolefins (e.g. polypropylene). A polyolefin is a polymer derived from two or more olefins (ie alkenes). An olefin (i.e. alkene) is a hydrocarbon containing at least one carbon-carbon double bond. The olefin may be a monoene (ie an olefin having only a single carbon-carbon double bond), diene (ie an olefin having two carbon-carbon double bonds), triene (ie an olefin having three double bonds) carbon-carbon), tetraene (ie, an olefin having four double carbon-carbon bonds), and other polyenes. The olefin or alkene, such as monoene, diene, triene, tetraene and other polyenes, may have 3 or more carbon atoms, 4 or more carbon atoms, 6 or more carbon atoms, 8 or more carbon atoms. In some embodiments, the olefin has from 3 to about 100 carbon atoms, from 4 to about 100 carbon atoms, from 6 to about 100 carbon atoms, from 8 to about 100 carbon atoms, from 3 to about 100 carbon atoms. about 50 carbon atoms, from 3 to about 25 carbon atoms, from 4 to about 25 carbon atoms, from 6 to about 25 carbon atoms, from 8 to about 25 carbon atoms, or from 3 to about 25 carbon atoms. at about 10 carbon atoms. In some embodiments, the olefin is a linear or branched monocyclic or acyclic monoene having from 2 to about 20 carbon atoms. In other embodiments, alkene is a diene such as butadiene and 1,5-hexadiene. In further embodiments, at least one of the alkene hydrogen atoms is substituted with alkyl or aryl. In particular embodiments, the alkene is ethylene, propylene, 1-butene, 1-hexene, 1-octene, 1-decene, 4-methyl-1-pentene, norbornene, butadiene, 1,5-hexadiene, styrene or a combination of the same. same.

The amount of polyolefins in the polymer mixture may be from about 0.5 to 99 weight percent, from about 10 to about 90 weight percent, from about 20 to about 80 weight percent. from about 30 to about 70 weight percent, from about 5 to about 50 weight percent, from about 50 to about 95 weight percent, from about 10 to about 50 weight percent. by weight, or from about 50 to about 90 weight percent of the total weight of the polymer blend.

Any polyolefin known to a person of ordinary skill in the art may be used to prepare the polymeric mixture disclosed herein. The polyolefins may be olefin homopolymers, olefin copolymers, olefin terpolymers, olefin quaterpolymers and the like, and combinations thereof.

In some embodiments, one of at least two polyolefins is an olefin homopolymer. The olefin homopolymer may be derived from an olefin. Any olefin homopolymer known to one of ordinary skill in the art may be used. Non-limiting examples of olefin homopolymers include polyethylene (e.g., ultra low, low, low linear, medium, high and ultra high density), polypropylene, polybutylene (e.g. polybutene-1), polypentene-1, polyhexene -1, polyoctene-1, polydecene-1, poly-3-methylbutene-1, poly-4-methylpentene-1, polyisoprene, polybutadiene, poly-1,5-hexadiene.

In further embodiments, the olefin homopolymer is a polypropylene. Any polypropylene known to one of ordinary skill in the art may be used to prepare the polymeric mixtures disclosed herein. Non-limiting examples of polypropylene include polypropylene (LDPP), high density polypropylene (HDPP), high melt resistance polypropylene (HMS-PP), high impact polypropylene (HIPP), isotactic polypropylene (iPP), syndiotactic polypropylene (sPP) and the like, and combinations thereof.

The amount of polypropylene in the polymer blend may be from about 0.5 to 99 weight percent, from about 10 to about 90 weight percent, from about 20 to about 80 weight percent. from about 30 to about 70 weight percent, from about 5 to about 50 weight percent, from about 50 to about 95 weight percent, from about 10 to about 50 weight percent. by weight, or from about 50 to about 90 weight percent of the total weight of the polymer blend. Cross-linking The fibers may be cross-linked by any means known in the art, including, but not limited to, electron beam irradiation, beta irradiation, gamma irradiation, crown irradiation, silanes, peroxides, allyl compounds, and UV radiation. with or without cross-linking catalyst. U.S. Patent No. 10 / 086,057 (published as US2002 / 0132923 A1) and U.S. Patent No. 6,803,014 disclose electron beam irradiation methods that can be used in embodiments of the invention.

[0158] Irradiation can be performed using high energy, ionizing electrons, ultraviolet rays, x-rays, gamma rays, beta particles and the like and combinations thereof. Preferably, electrons are employed in dosages of up to 70 mega rads. The irradiation source may be any electron beam generator in a range from about 150 kilovolts to about 6 megavolts with an output power capable of delivering the desired dosage. The voltage may be adjusted to appropriate levels which may be, for example, 100,000, 300,000, 1,000,000 or 2,000,000 or 3,000,000 or 6,000,000 or higher. Many other apparatus for radiating polymeric materials are known in the art. Irradiation is usually performed at a dosage of from about 3 mega-rads to about 35 mega-rads, preferably from about 8 to about 20 mega-rads. Additionally, irradiation may conveniently be performed at room temperature, although higher or lower temperatures may be employed, for example from 0 ° C to about 60 ° C. Preferably, irradiation is performed after conformation or fabrication of the article. Also, in a preferred embodiment, the propylene interpolymer that has been incorporated with a pro-rad additive is irradiated with electron beam radiation at about 8 to about 20 mega rads.

Crosslinking can be stimulated with a crosslinking catalyst, and any catalyst that will provide this function can be used. Suitable catalysts generally include organic bases, carboxylic acids, and organic and complex organometallic compounds titanates and lead, cobalt, iron, nickel, zinc and tin carboxylates. Dibutyl tin dilaurate, dioctyl tin maleate, dibutyl tin diacetate, dibutyl tin dioctate, stannous acetate, stannous octoate, lead naphthenate, zinc caprylate, cobalt naphthenate and the like. Tin carboxylate, especially dibutyl tin dilaurate and dioctyl maleate are particularly effective for this invention. The catalyst (or mixture of catalysts) is present in a catalytic amount, typically between about 0.015 and about 0.035 phr.

Representative pro-rad additives include, but are not limited to, azo compounds, organic peroxides, and polyfunctional vinyl or allyl compounds such as, for example, triallyl cyanurate, triallyl isocyanurate, pentaerythritol tetramethacrylate, glutaraldehyde, dimethacrylate ethylene glycol, diallyl maleate, dipropargyl maleate, dipropargyl monoalyl cyanurate, dicumyl peroxide, di-terciobutyl peroxide, benzoyl perbenzoate, cumene hydroperoxide, terciobutyl peroctoate, methyl peroxide, methyl peroxide , 5-dimethyl-2,5-di (tertiary butyl peroxy) hexane, lauryl peroxide, tertiary butyl peracetate, azo-bis-isobutyl nitrite and the like and combinations thereof. Preferred pro-rad additives for use in the present invention are compounds having polyfunctional (i.e. at least two) moieties such as C = C, C = N or C = 0.

At least one pro-rad additive may be introduced to the propylene interpolymer by any method known in the art. Preferably, however, the pro-rad additives are introduced via a standard blend concentrate comprising the same or a different base resin than the propylene interpolymer. Preferably, the pro-rad additive concentration for the standard mixture is relatively high, for example, about 25 weight percent (based on the total weight of the concentrate).

At least one pro-rad additive is introduced into the propylene polymer in any effective amount. Preferably, the amount of pro-rad additive introduction is from about 0.001 to about 5 weight percent, more preferably from about 0.005 to about 2.5 weight percent, and most preferably from about 0.015 to about 5 weight percent. 1 weight percent (based on the total weight of the propylene interpolymer).

[0163] In addition to electron beam irradiation, crosslinking can also be performed by UV irradiation. U.S. Patent No. 6,709,742 discloses a UV irradiation crosslinking method that can be used in embodiments of the invention. The method comprises mixing a photoinitiator, with or without a photo crosslinker, with a polymer before, during or after the fiber has formed and then exposing the fiber with the photoinitiator to UV radiation sufficient for crosslinker to the desired level. The photoinitiators used in the practice of the invention are aromatic ketones, for example benzophenones or 1,2-diketone monoacetals. The main photoreaction of monoacetals is the homolytic division of the α bond to give acyl or dialkoxyalkyl radicals. This type of α-divide is known as a type I Norrish reaction that is more fully described in W. Horspool and D. Armesto, "Organic Photochemistry: A Comprehensive Treatment", Ellis Horwood Limited, Chichester, England, 1992; J. Kopecky, "Organic Photochemistry: A Visual Approach", VCH Publishers, Inc., New York, NY, 1992; N.J. Turro, et al., Acc. Chem. Res, 1972, 5, 92; and J.T. Banks, et al., J. Am. Chem. Soc. 1993; 115; 2473

The synthesis of aromatic 1,2-diketone mono-acetals, Ar-CO-C (OR) 2-Ar ', is described in USP 4,190,602 and in Ger. Offen No. 2,337,813. The preferred compound of this class is 2,2-dimethoxy-2-phenyl acetophenone, commercially obtainable C6H5-CO-C (OCH3) 2-06 comercial5 from Ciba-Geigy as IRGACURE 651. Examples of other useful aromatic ketones in the practice of this invention as photoinitiators, IRGACURE 184, 369, 819, 907 and 2959, all obtainable from Ciba-Geigy.

[0165] In one embodiment of the invention, the photoinitiator is used in combination with a photo crosslinker. Any photo cross-linker which, in response to free radical generation, will link two or more polyolefin backbones to one another by forming covalent bonds with the backbones can be used in this invention. Preferably, these photo cross-linkers are polyfunctional, that is, they comprise two or more sites which in response to activation will form a covalent bond with a copolymer backbone site. Representative photo cross-linkers include, but are not limited to polyfunctional vinyl or allyl compounds such as, for example, triallyl cyanurate, triallyl isocyanurate, pentaerythritol tetramethacrylate, ethylene glycol dimethacrylate, diallyl maleate, dipropargyl maleate, cyanurate dipropargyl monoalyl and the like. Preferred photo cross-linkers for use in the present invention are compounds which have polyfunctional (i.e. at least two) portions. Particularly preferred photo cross-linkers are triallyl cyanurate (TAC) and triallyl isocyanurate (TAIC).

In the practice of this invention, certain compounds act as both a photoinitiator and a photo cross-linker. These compounds are characterized by the ability to generate two or more reactive species (eg free radicals, carbenes, nitrenes, etc.) in response to exposure to UV radiation and subsequent covalent bonding with two polymer chains. Any compound performing these two functions may be used in the practice of this invention, and representative compounds include the sulfonyl azides described in USP 6,211,302 and 6,284,842.

In another embodiment of this invention, the copolymer is subjected to secondary cross-linking, i.e. cross-linking other than and beyond photo cross-linking. In this embodiment, the photoinitiator is used either in combination with a non-photo crosslinker, for example a silane, or the copolymer is subjected to a secondary crosslinking procedure, for example exposure to electron beam radiation. Representative examples of silane crosslinkers are described in USP 5,824,718, and crosslinking through exposure to electron beam radiation is described in USP 5,525,257 and 5,324,576. Use of a photo crosslinker in this embodiment is optional.

At least one photoadditive, i.e. photoinitiator and optional photo crosslinker may be introduced into the copolymer by any method known in the art. However, preferably the photo additives are introduced via a standard blend concentrate comprising the same or a different base resin than the copolymer. Preferably, the concentration of photo additive in the standard mixture is relatively high, for example, about 25 weight percent (based on total weight of concentrate).

At least one photo additive is introduced into the copolymer in any effective amount. Preferably, the amount of introduction of the at least one photoadditive is from about 0.001 to about 5, more preferably from about 0.005 to about 2.5 and most preferably from about 0.015 to about 1 weight percent. (based on total copolymer weight).

[0170] Optional photoinitiators and photo-crosslinkers may be added during different stages of the fiber or film manufacturing process. If the photo additives can withstand the extrusion temperature, a polyolefin resin may be mixed with additives before being fed into the extruder, for example via a standard admixture addition. Alternatively, additives may be introduced into the extruder just prior to the die slit, but in this case efficient mixing of components prior to extrusion is important. In another approach, the polyolefin fibers may be stretched without photoadditives, and a photoinitiator and / or photo crosslinker may be applied to the extruded fiber via contact roller, spraying, dipping in a solution with additives, or using other industrial methods. for aftertreatment. The resulting fiber with photoadditives is then cured via electromagnetic radiation in a continuous or batch process. The photo additives may be mixed with the polyolefin using conventional compositing equipment including single or twin screw extruders.

The power of electromagnetic radiation and the irradiation time are chosen to allow efficient crosslinking without degradation and / or dimensional defects of the polymer. The preferred process is described in EP 0 490 854 Bl. Photo additives of sufficient thermal stability are premixed with a polyolefin resin, extruded into a fiber, and irradiated in a continuous process using a power source or several units connected in series. There are several advantages to using a continuous process compared to a batch process to cure a fiber or sheet of an interlaced cloth that is collected in a coil.

[0172] Irradiation may be performed by the use of UV radiation. Preferably, UV radiation to an intensity of 100 J / cm2 is employed. The irradiation source may be any UV radiation generator operating in a range of 50 watts to about 25000 watts with an output power capable of providing the desired dosage. For example, the power may be adjusted to appropriate levels which may be, for example, 1000 watts or 4800 watts or 6000 watts or less or greater. Many other apparatus for UV irradiating polymeric materials are known in the art. Usually, irradiation is performed at a dosage of from about 3 J / cm2 to about 500 J / cm2, preferably from about 5 J / cm2 to about 100 J / cm2. Additionally, irradiation may conveniently be performed at room temperature, although higher or lower temperatures may be employed, for example from 0 ° C to about 60 ° C. The photo cross-linking process is faster at higher temperatures. Preferably, irradiation is performed after conformation or fabrication of the article. In a preferred embodiment, the copolymer which has been incorporated with a photo additive is irradiated with UV radiation at about 10 J / cm 2 to about 50 J / cm 2.

Other Additives Antioxidants, for example IRGAFOS 168, IRGANOX 1010, IRGANOX 3790, and CHIMASSORB 944 produced by Ciba-Geigy Corp., may be added to the propylene polymer to protect against destructive degradation during molding or fabrication operation and / or to better control graft extension or crosslinking (ie inhibit excessive gelation). Ongoing additives, for example calcium stearate, water, fluorinated polymers, etc. may also be used for purposes such as deactivating residual catalyst and / or improving processability. TINUVIN 770 (from Ciba-Geigy) can be used as a light stabilizer.

[0174] The copolymer may or may not contain charge. If it contains a load, then the amount of charge present should not exceed an amount that would adversely affect thermal resistance or elasticity at a high temperature. If present, the amount of filler is between 0.01 and 80 weight percent, based on the total weight of the copolymer (or if it is a mixture of one copolymer and one or more other polymers, then the total weight of the mixture). Representative fillers include kaolin, clay, magnesium hydroxide, zinc oxide, silica and calcium carbonate. In a preferred embodiment, in which a filler is present, the filler is coated with a material that will prevent or retard any tendency the filler may have to interfere contrary with the crosslinking reactions. Stearic acid is an example of such a filler coating.

To reduce the coefficient of friction of fibers, various spin finish formulations may be used, such as metal soaps dispersed in textile oils (see, for example, U.S. Patent Nos. 3,039,895 and 6,652,599), surfactants. in an oil base (see for example US publication 2003/0024052) and poly (alkyl siloxanes) (see, for example, US Patent No. 3,296,063 or US Patent No. 4,999,120). U.S. Patent Application No. 10 / 933,721 (published as US20050142360) discloses spinning finish compositions which may also be used.

The following examples are given to illustrate embodiments of the invention, but without intending to limit the invention to the specific embodiments shown. Unless otherwise indicated, all parts and percentages are by weight. All numeric values are approximate. When numerical ranges are given, it is to be understood that embodiments outside the stated ranges will still fall within the scope of the invention. Specific details, described in each of the examples, should not be construed as necessary features of the invention.

Example 1 A propylene / ethylene block copolymer having about 12 weight percent ethylene and about 88 weight percent propylene, (soft segment composition), a melt flow rate, MFR , measured by ASTM D 1238, 230 ° C / 2.16 kg condition, about 25 g / 10 minutes, and an overall density of about 0.877 g / cm3, and an estimated hard segment content of about 30% and soft segment content of about 70% is heat-welded to thin denier fiber (less than about 4 denier / filament) using a heat-sealing apparatus. The melt spinning temperature is about 245 ° C, the operating productivity is 0.5 ghm (gram / min / hole) and the fibers are melt drawn from a spinneret diameter of about 600 microns decreasing to fiber diameter from about 2 to less than 4 denier per filament. The resulting nonwoven cloth is then heat bonded at a temperature of about 200-220 ° C and at a pressure sufficient to stitch the fibers together. The individual fibers are measured for mechanical properties, and have a tensile strength limit of about 0.5-1 gram / denier, an elongation at break of about 150-270%, a permanent deformation of about 3- 12% (2-cycle hysteresis at 100% strain), a modulus of about 5-15 grams / denier, and a melting point of about 160 ° C. The resulting nonwoven cloth has a basis weight of about 30 g / m 2 and physical properties of elongation to rupture in MD of about 200%, and elongation to rupture in DT of about 330%,% of adjustment in MD about 8% and TD adjustment of about 8%.

Example 2 A propylene / ethylene block copolymer having about 12 weight percent ethylene and about 88 weight percent propylene, a melt flow rate, MFR, as measured by ASTM D 1238, 230 ° C / 2.16 kg condition, about 9 g / 10 minutes, and an overall density of about 0.875 g / cm3, and an estimated hard segment content of about 30% and soft segment content of about 70% is thermosolded in 40 denier fiber (monofilament) using a heat sealing apparatus. The melt spinning temperature is about 245 ° C, and the fibers are melt-drawn from a die diameter of about 800 microns decreasing to a diameter of 40 denier at a compensation speed of 550 m / s. min The fibers in the form of coils are measured for mechanical properties (prior to crosslinking), and have a tensile strength limit of about 1-1.5 gram / denier, an elongation to break of about 450-500%, a permanent deformation of about 40-60% (300% deformation in 5 cycles, BISFA method), a modulus of about 5-15 gram / denier, and a melting point of about 160 ° C.

Example 3 A propylene / ethylene block copolymer having about 12 weight percent ethylene and about 88 weight percent propylene (soft segment composition), a melt flow rate, MFR , measured by ASTM D 1238, condition 230 ° C / 2.16 kg, about 50 g / 10 minutes, and an overall density of about 0.877 g / cm3, and an estimated hard segment content of about 30% and about 70% soft segment content is heat sealed to microdenier fiber (less than about 1.5 denier / filament) using a heat sealing apparatus. The melt spinning temperature is about 245 ° C, the operating productivity is 0.5 ghm (gram / min / orifice) and the fibers are melt drawn from a spinneret diameter of about 600 microns decreasing to fiber diameter of about 1-1.5 denier per filament. Individual fibers are measured for mechanical properties, and have a tensile strength limit of about 2.5-3 grams / denier, an elongation at break of about 50-100%, a permanent deformation of about 35- 45% (2-cycle hysteresis at 100% strain), and a melting point of about 160 ° C.

As described above, embodiments of the invention provide fibers made from single block copolymers of propylene and α-olefin. The fibers may have one or more of the following advantages: good abrasion resistance; low coefficient of friction, high upper service temperature; high recovery / retraction force; low relaxation tension (at high and low temperatures); soft stretching; high elongation at break; chemical resistance: inert; UV resistance. The fibers may be spun fused at relatively high spin rates and lower temperature. The fibers may be crosslinked by electron beam or by other irradiation methods. In addition, the fibers are less sticky, resulting in better unwinding performance and better shelf life, and are substantially free of stringing (i.e. fiber bundling). As the fibers can be spun at a higher spin rate, the operational productivity of fiber production is high. Such fibers have large forming windows and large processing windows. Other advantages and features are apparent to those skilled in the art.

Although the invention has been described with respect to a limited number of embodiments, the specific characteristics of one embodiment should not be attributed to the other embodiments of the invention. No single embodiment is representative of all aspects of the invention. In some embodiments, the compositions or methods may include numerous compounds or steps not mentioned herein. In other embodiments, the compositions or methods do not include, or are substantially free of any compounds or steps not enumerated herein. There are variations and modifications of the embodiments described. The method of making the resins is described as comprising various actions or steps. These steps or actions may be performed in any sequence or order unless otherwise indicated. Finally, any number disclosed herein should be construed to mean approximate, regardless of whether the term "about" or "approximately" is used in describing the number. The appended claims are intended to encompass all modifications and variations to be embraced by the scope of the invention.

Claims (23)

A fiber obtainable from or comprising a propylene / α-olefin multiblock interpolymer, comprising at least 50 mole percent, of the entire propylene polymer, characterized in that the propylene / α-olefin multiblock interpolymer comprises at least a hard block and at least one soft block linearly bonded, the propylene / α-olefin multiblock interpolymer having one or more of the following properties: (a) a Mw / Mn of 1.7 to 3.5 by minus one melting point, Tm, in degrees Celsius, and a density, d, in grams / cubic centimeter, where the numerical values of Tm and d correspond to the ratio: Tm> -2002,9 + 4538,5 (d ) - 2422.2 (d) 2; or (b) a Mw / Mn of 1,7 to 3,5, and a heat of fusion, ΔΗ in J / g, and a delta amount, ΔΤ, in degrees Celsius defined as the temperature difference between the DSC peak. highest and the highest CRYSTAF peak, with the numerical values of ΔΤ and ΔΗ having the following ratios: ΔΤ> -0.1299 (ΔΗ) +62.81 for ΔΗ greater than zero and up to 130 J / g, AT> 48 ° C for ΔΗ greater than 130 J / g, and the CRYSTAF peak is determined using at least 5 percent of the cumulative polymer, and if less than 5 percent of the polymer has an identifiable CRYSTAF peak, then the CRYSTAF temperature will be 30 ° C; or (c) an elastic recovery, Re, 300 percent creep percentage and 1 cycle measured with a compression molded propylene / α-olefin multiblock interpolymer film, and a density, d, in grams / cubic centimeter, wherein the R e ed values satisfy the following relationship when the propylene / α-olefin multiblock interpolymer is free of a cross-linked phase: Re> 1481 - 1629 (d); or (d) a comonomer content in the TREF fraction eluting between 40 ° C and 130 ° C greater than or equal to the amount (-0,2013) 1 + 21.07, where T is the numerical value of the peak elution temperature of ATREF measured in ° C. Fiber according to claim 1, characterized in that the propylene / α-olefin multiblock interpolymer has an elastic recovery, Re, 300 percent creep percentage and 1 cycle measured with a multiblock interpolymer film compression-molded propylene / α-olefin and a density, d, in grams / cubic centimeter, where elastic recovery and density satisfy the following relationship when the propylene / α-olefin multiblock interpolymer is free of a cross-linked phase : Re> 1481-1629 (d) Fiber according to Claim 1, characterized in that the propylene / α-olefin multiblock interpolymer has at least one melting point, Tm, in degrees Celsius, and density, d, in grams / cubic centimeter, where the numerical values of the variables correspond to the ratio: Tm> -2002.9 + 4538.5 (d) - 2422.2 (d) 2 and the interpolymer having a Mw / Mn of 1.7 to 3.5 . Fiber according to Claim 1, characterized in that the propylene / α-olefin multiblock interpolymer having a Mw / Mn of 1.7 to 3.5 has a melt heat, ΔΗ, in J / g , and a delta quantity, ΔΤ, in degrees Celsius defined as the temperature difference between the highest DSC peak minus the highest CRYSTAF peak, the numerical values of ΔΤ and ΔΗ satisfying the following ratios: Δΐ> -0,1299 ( ΔΗ) + 62.81 for ΔΗ greater than zero and up to 130J / g, or ΔΤ> 48 ° C for ΔΗ greater than 130 J / g, the CRYSTAF peak being determined using at least 5 percent of the cumulative polymer, and if less than 5 percent of the polymer has an identifiable CRYSTAF peak, then the CRYSTAF temperature will be 30 ° C. A fiber obtainable from or comprising a propylene / α-olefin multiblock interpolymer, comprising at least 50 mole percent, of the entire propylene polymer, characterized in that the propylene / α-olefin multiblock interpolymer comprises at least a hard block and at least one soft block bonded in a linear manner, the propylene / α-olefin multiblock interpolymer having an average block index of 0.1 to 0.3 and a molecular weight distribution, Mw / Mn, greater than 1.3. 6. Fiber obtainable from or comprising at least one multiblock interpolymers of propylene and α-olefin C2 or C4-C2 (not characterized in that said multiblock interpolymer comprises at least 50 mole percent of the entire polypropylene polymer; wherein the multiblock interpolymer comprises at least one hard block and at least one linearly bonded soft block, the propylene / α-olefin multiblock interpolymer having a density of 0.860 g / cm3 to 0.895 g / cm3 and an adjustment compression at 70 ° C less than 70%. Fiber according to any one of claims 1, 2, 3, 4, or 5, characterized in that α-olefin is styrene, ethylene, 1-butene, 1-hexene, 1-octene, 4-methyl -1-pentene, 1-decene, or a combination thereof. Fiber according to any one of claims 1, 2, 3, 4, or 5, characterized in that it is cross-linked. Fiber according to any one of claims 1, 2, 3, 4, or 5, characterized in that the propylene / α-olefin multiblock interpolymer is mixed with another polymer. Fiber according to any one of claims 1, 2, 3, 4, or 5, characterized in that it is a two-component fiber. Fiber according to Claim 8, characterized in that the crosslinking is effected by photon irradiation, electron beam irradiation, or by a crosslinking agent. Fiber according to Claim 8, characterized in that the cross-linked polymer is at least 20 percent metered by weight percent of formed gels. Fiber according to any one of claims 1, 2, 3, 4, 5, or 6, characterized in that it has a coefficient of friction of less than 1.2, wherein the interpolymer is not mixed with any load. Cloth comprising the fiber as defined in any one of claims 1, 2, 3, 4, 5, or 6. Cloth according to Claim 14, characterized in that it comprises fibers made by spinning in solution. Cloth according to claim 14, characterized in that it is elastic. Cloth according to claim 14, characterized in that it is woven. Cloth according to claim 14, characterized in that it has a percent machine direction (MD) recovery of at least 50 percent in 100 percent deformation. A yarn comprising the fiber as defined in any one of claims 1, 2, 3, 4, 5, or 6. A yarn according to claim 19, characterized in that it is covered. Yarn according to claim 20, characterized in that it is covered with cotton yarns or nylon yarns. A method of making a fiber comprising: melting a propylene / α-olefin multiblock interpolymer, said interpolymer comprising at least one hard block and at least one linearly bonded soft block, the propylene multiblock interpolimer / α-olefin comprising at least 50 mol percent of the entire propylene polymer; and extruding the propylene / α-olefin multiblock interpolymer into a fiber, wherein the propylene / α-olefin multiblock interpolymer is characterized in that it comprises one or more of the following properties: (a) a Mw / Mn of 1, 7 to 3,5, at least one melting point Tm in degrees Celsius and a density d in grams / cubic centimeter, where the numerical values of Tm and d correspond to the ratio: Tm> -858, 91 - 1825, 3 (d) + 1112.8 (d) 2; or (b) a Mw / Mn of 1,7 to 3,5, and a heat of fusion, ΔΗ in J / <Jr and a delta amount, ΔΤ, in degrees Celsius defined as the temperature difference between the DSC peak. highest and the highest CRYSTAF peak, with the numerical values of ΔΤ and ΔΗ having the following ratios: ΔΤ> -0.1299 (ΔΗ) +62.81 for ΔΗ greater than zero and up to 130J / gA AT> 48 ° C for ΔΗ greater than 130 J / g, and the CRYSTAF peak is determined using at least 5 percent of the cumulative polymer, and if less than 5 percent of the polymer has an identifiable CRYSTAF peak, then the CRYSTAF temperature will be 30 ° C. ° C; or (c) an elastic recovery, Re, 300 percent creep, and 1 cycle measured with a compression molded propylene / α-olefin multiblock interpolymer film, and a density, d, in grams / cubic centimeter , where the numerical values of Re ed satisfy the following relationship when the propylene / α-olefin multiblock interpolymer is free of a cross-linked phase: Re> 1481 - 1629 (d); or (d) a comonomer content in the TREF fraction, eluting between 402 ° C and 130 ° C greater than or equal to the amount (-0,2013) T + 21.07, where T is the numerical value of the peak elution temperature. ATREF measured in ° C. Method according to claim 22, characterized in that a cloth formed from the fiber is free of stranding.