JP2008248039A - Polymer crystal and method for producing the same - Google Patents

Abstract

[PROBLEMS] To provide a polymer crystal having excellent mechanical strength, heat resistance, transparency and other properties, particularly in general-purpose plastics including PP, such as mechanical strength, heat resistance and transparency. The present invention provides a polymer crystal body, particularly a bulk molded body of the polymer crystal body.
A polymer crystal according to the present invention is a polymer crystal containing a polymer crystal and a nucleating agent, and comprises the following conditions (I), (II) and (III): The conditions of I), (II) and (III ′) are satisfied. (I) Contains 0.1 to 0.5% by weight of nucleating agent. (II) The crystallinity of the polymer crystal is 70% or more. (III) The size of the polymer crystal is 300 nm or less. (III ′) The number density of the polymer crystals is 40 μm ⁻³ or more.
[Selection figure] None

Description

  The present invention relates to a polymer crystal having excellent properties such as mechanical strength, heat resistance, and transparency, and a method for producing the same. More preferably, the present invention relates to a bulk molded body of polymer crystals having the above-mentioned excellent characteristics and a method for producing the same.

  So-called “general-purpose plastics” including polyethylene (hereinafter referred to as “PE”), polypropylene (hereinafter referred to as “PP”), polystyrene (hereinafter referred to as “PS”), polyvinyl chloride (hereinafter referred to as “PVC”), Not only is it less expensive at less than 100 yen / kg, but it is easy to mold and weighs a fraction of the weight of metals and ceramics, so bags, various packaging, various containers, sheets, etc. It is often used as a variety of daily necessities, industrial parts such as automobiles and electricity, daily necessities, and miscellaneous goods.

  However, the general-purpose plastic has drawbacks such as insufficient mechanical strength and low heat resistance. Therefore, the above-mentioned general-purpose plastic does not have sufficient characteristics required for materials used in various industrial products such as automobiles and other industrial products such as electrical, electronic and information products. Is currently limited. For example, in the case of PE, the softening temperature is usually about 90 ° C. Even PP, which has relatively high heat resistance, usually softens at about 130 ° C. In addition, PP has insufficient transparency compared to polycarbonate (hereinafter referred to as “PC”), polyethylene terephthalate (hereinafter referred to as “PET”), PS, and the like, and therefore cannot be used as an optical material, a bottle, or a transparent container. Has the disadvantages.

  On the other hand, so-called “engineering plastics” such as PET, PC, fluororesin (Teflon (registered trademark)), nylon, polymethylpentene, polyoxymethylene, acrylic resin, etc. are excellent in mechanical strength, heat resistance, transparency, etc. Usually, it does not soften at 150 ° C. Therefore, engineering plastics are used as materials for various industrial products and optical materials that require high performance such as automobiles, mechanical products, and electrical products. However, engineering plastics are very expensive at several hundred yen / kg to several thousand yen / kg, and engineering plastics have serious disadvantages such as the fact that monomer recycling is difficult or impossible and the environmental burden is very large. Have.

Therefore, by significantly improving the material properties of general-purpose plastics such as mechanical strength, heat resistance, and transparency, if the general-purpose plastics can be used as an alternative to engineering plastics, or as an alternative to metal materials, It is possible to greatly reduce the costs of various industrial products and daily products made of molecules and metals, and to save energy and improve operability by reducing the weight. For example, PET is currently used as a bottle for beverages including soft drinks, but if such PET can be replaced with PP, the cost of the bottle can be greatly reduced. . Moreover, it is possible for PET to perform monomer recycling. However, because it is not easy to recycle PET monomer, used PET bottles are cut and discarded after being reused once or twice for low-quality applications such as clothing fibers and films. is the current situation. On the other hand, since PP can be easily recycled, complete recycling can be realized, and there is an advantage that consumption of fossil fuels such as petroleum and generation of carbon dioxide (CO ₂ ) can be suppressed.

  As described above, in order to improve the properties of general-purpose plastics such as mechanical strength, heat resistance, and transparency, and to use general-purpose plastics as an alternative to engineering plastics and metals, the proportion of crystals in PP and PE (crystals It is required to produce a crystal body consisting only of crystals that substantially increase the degree of conversion), and more preferably contains almost no PP or PE amorphous material. In particular, PP has the advantage of higher mechanical strength and higher heat resistance than PE, so it is highly expected and is an important polymer that maintains a high annual output rate of several percent. It is.

  Here, as a method for improving the crystallinity of the polymer, a method of decreasing the cooling rate of the polymer melt is known. However, this method has not only an insufficient increase in crystallinity, but also has a drawback that the productivity of the product is remarkably reduced, and the crystal grain size becomes coarse and the mechanical strength is reduced. As another method, there has been proposed a method in which a polymer melt is cooled under high pressure to increase crystallinity. However, in this method, it is necessary to pressurize the polymer melt to several hundred atmospheres or more, which is theoretically possible, but it is difficult to design a manufacturing apparatus in industrial scale production, and the production cost is high. turn into. Therefore, the above method is practically difficult. As another method for improving the crystallinity of the polymer, a method of adding a nucleating agent to the polymer melt is known. However, with the current method of adding a nucleating agent, the degree of crystallinity is 40-50% at most, which is not sufficient. Accordingly, a method for dramatically improving the crystallinity in a polymer such as general-purpose plastic and a method for producing a polymer crystal have not been completed at present.

  By the way, according to many studies so far, a polymer melt (referred to as an “isotropic melt”) in which molecular chains in the melt exist in a disordered form (for example, a string shape (random coil)) By crystallizing in a shear flow field, the characteristic crystal form (shish) of a thin fiber with a thickness of several μm oriented along the flow, and a 10 nm thick thin plate crystal and amorphous It has been clarified that a kebab formed in a sandwich shape is sparsely formed in the melt (see Non-Patent Document 1). The above state is called “shish-kebab” (meaning yakitori “skewer” and “meat”).

  In the initial stage of shish-kebab generation, only shish is generated sparsely. The structure of shish is “extended chain crystal (ECC)” in which the molecular chain is stretched and crystallized (see Non-Patent Document 5). It is considered to be a “folded chain crystal (FCC)” that is folded on the surface of The molecular mechanism of shish-kebab was not clear because there were no examples based on kinetic studies. Folded chain crystals are thin plate crystals (referred to as lamellar crystals) that are most commonly found in polymer crystals. In addition, when injection molding is performed on a mold, a thin crystalline film with a thickness of several hundred μm called “skin” on the surface, and a “laminated structure (laminated lamellar structure) of folded chain crystals called amorphous and amorphous inside. It is well known that an aggregate of “)” is formed (see Non-Patent Document 6). The skin is thought to be made of shish-kebab, but it has been confirmed that shish exists only sparsely. The generation mechanism of the skin structure has not been elucidated because there are no examples based on kinetic studies.

  The present inventors have studied the kinetics of the shish formation mechanism for the first time, and some molecular chains in the melt are stretched at the foreign substance interface due to “topological interaction” with the interface. Clarified the mechanism that shish is formed in a part of the melt in order to become a liquid crystal-oriented melt (referred to as "orientated melt" or "Oriented melt") (for example, non-patent literature) 2 and 3). Here, the “topological interaction” means an effect of “stretching each other because the string-like polymer chains are entangled”, and is known as an interaction inherent to the polymer. The present inventors have proposed the theory of topological crystallization mechanism of polymers for the first time, and have elucidated the origin of extended chain crystals and folded chain crystals. This theory is called “slip diffusion theory” and is recognized worldwide (see Non-Patent Document 7).

In addition, the present inventors have found that in the shear crystallization, the molecular chain is found in the shear crystallization from the elucidation of the formation mechanism of the “spiralite” discovered in the shear flow crystallization of low shear rate = 0.01 to 0.1 s ^−1. A universal mechanism has been proposed theoretically (see Non-Patent Document 4) in which an oriented melt is generated by stretching and the nucleation and growth rates are significantly accelerated.

  Therefore, if the entire polymer melt can be made into an oriented melt, it can be said that crystallization of the polymer is likely to occur and the crystallinity can be increased. Here, the polymer melt as a whole is referred to as “bulk alignment melt”. Furthermore, if the entire polymer melt can be crystallized in the state of an oriented melt, a crystal having a structure in which most of the molecular chains of the polymer are oriented (this is called a bulk "polymer oriented crystal" It is expected that it can be produced. In this case, nucleation is further promoted, the crystal size can be reduced to the nanometer order, and a polymer having high transparency and greatly increased mechanical strength and heat resistance can be obtained. It is also expected to be possible.

We have established a means to determine the critical elongation strain rate so far. Then, by stretching the polymer melt at a strain rate equal to or higher than the determined critical elongation strain rate, the polymer melt is brought into an oriented melt state, and further, the oriented melt state of the polymer melt is maintained. The polymer oriented crystal was successfully obtained by cooling while cooling. In the above method, a polymer oriented crystal having a high crystallinity can be obtained without using a nucleating agent.
A. Keller, MJMachin, J. Macromol. Sci., Phys., B2, 501 (1968) S. Yamazaki, M. Hikosaka et al, Polymer, 46, 2005, 1675-1684. S. Yamazaki, M. Hikosaka et al, Polymer, 46, 2005, 1685-1692. K. Watanabe et al, Macromolecules 39 (4), 2006, 1515-1524. B. Wunderlich, T. Arakawa, J. Polym. Sci., 2, 3697-3706 (1964) Mitsumi Fujiyama, “Structure of the skin layer of polypropylene injection molding”, Polymer Journal, 32 (7), PP411-417 (1975) M. Hikosaka, Polymer 1987 28 1257-1257

  The object of the present invention is to improve the crystallinity of the polymer crystal by improving the crystallization efficiency of the polymer in the polymer crystal production method established by the present inventors. . Furthermore, an object of the present invention is to obtain a bulk molded body of a polymer crystal having a certain thickness or more.

  As a result of intensive studies to solve the above problems, the present inventors have blended a predetermined amount of a fine nucleating agent (nanonucleating agent) into the polymer melt, and the strain rate is equal to or higher than the critical elongation strain rate. Thus, it was discovered that by stretching and cooling the polymer melt, a bulk molded body of polymer crystals can be obtained, and the present invention has been completed. As described below, a bulk molded body of a polymer crystal having a high crystallinity and an extremely small crystal size (an extremely high number density) has not been found so far.

That is, the present invention provides a polymer crystal comprising a polymer crystal and a nucleating agent, wherein the polymer crystal satisfying the following conditions (I), (II) and (III): Include. (I) contains 0.1 to 0.5% by weight of nucleating agent;
(II) The crystallinity of the polymer crystal is 70% or more;
(III) The size of the polymer crystal is 300 nm or less.
The polymer crystal according to the present invention preferably has a polymer crystal size of 100 nm or less, and more preferably 20 nm or less.

Here, since the crystal size D ⁻³ = number density ν (μm ⁻³ ), the polymer crystal according to the present invention is a polymer crystal containing a polymer crystal and a nucleating agent,
It can be expressed that the following conditions (I), (II), and (III ′) are satisfied.
(I) contains 0.1 to 0.5% by weight of nucleating agent;
(II) The crystallinity of the polymer crystal is 70% or more;
(III ′) The number density of the polymer crystals is 40 μm ⁻³ or more.
The number density of the polymer crystals is preferably 10 ³ μm ⁻³ or more, and more preferably 10 ⁵ μm ⁻³ or more.

  The polymer crystal according to the present invention preferably contains 0.15 to 0.4% by weight of a nucleating agent.

  Moreover, the polymer crystal according to the present invention preferably has a crystallinity of 80% or more, and more preferably a crystallinity of 90% or more.

As described above, the polymer crystal according to the present invention has an extremely high crystallinity of 70% or more, an extremely fine crystal size of 300 nm or less, and a high crystal number density of 10 ² μm ⁻³ or more. Density. Therefore, the polymer crystal is excellent in properties such as mechanical strength, heat resistance, and transparency.

  The polymer is preferably a general-purpose plastic, particularly polypropylene. Since general-purpose plastics are inexpensive, it is very significant to use them as substitutes for metals and the like by giving them physical properties such as high mechanical strength. In addition, since PP can be completely recycled, it can be an extremely friendly material for the environment.

The polymer crystal according to the present invention comprises a polymer melt containing 0.1 to 0.5% by weight of a nucleating agent having a number average particle size of 0.1 μm or less at a strain rate equal to or higher than the critical elongation strain rate. Produced by a production method comprising an orientation melt process for extending the polymer melt into an oriented melt state, and a rapid crystallization process for cooling and crystallizing while maintaining the oriented melt state of the polymer melt It may be done. The production method may be a method including a critical elongation strain rate determination step of determining a critical elongation strain rate of the polymer melt. Here, the critical elongation strain rate determining step includes sandwiching a disk-shaped polymer melt having a radius x ₀ and a thickness 2z ₀ between transparent plates, cooling the polymer melt to a supercooled state, The molecular melt is crushed by a transparent plate at a constant speed v in the thickness direction, the critical point radius x ^{* at} which the polymer melt becomes an oriented crystal is measured, and ε ^* = αx ^{* 2} , where α = v / ( 2x ₀ ² z ₀ ), a step of calculating the critical elongation strain rate ε ^* from the equation. This is a step of measuring the critical point thickness 2z ^{* at} which the polymer melt becomes an oriented crystal and calculating the critical elongation strain rate ε ^* from the equation, ε ^* = (v / 2) z ^{* -1.} May be.

In the critical elongation strain rate determination step, a plate-like polymer melt having a center distance x ′ ₀ and a thickness of 2z ₀ and having a constant width is sandwiched between transparent plates, and the polymer melt is cooled and passed. After cooling, the polymer melt is crushed by a transparent plate at a constant speed v in the thickness direction, the critical point center distance x ′ ^{* at} which the polymer melt becomes an oriented crystal is measured, and ε ^* = αx ′ ^* , Where α = v / (x ′ ₀ z ₀ ) is a step characterized by calculating a critical elongation strain rate ε ^* from an equation.

As described above, in the methods established so far by the present inventors, a predetermined amount (0.1 to 0.5) of a fine nucleating agent (referred to as “nanonucleating agent”) having a number average particle size of 0.1 μm or less. By using a polymer melt containing (wt%), the crystallization efficiency of the polymer is further improved, and a polymer crystal having a high degree of crystallinity can be easily obtained. In addition, according to the above method, a bulk molded body of polymer crystals having a certain upper thickness can be obtained. To date, (II) a bulk molded product of a polymer crystal having a crystallinity of 70% or more and (III) a crystal size of the polymer of 300 nm or less, or (II) a polymer The crystallinity is 70% or more and
(III ′) A bulk molded product of polymer crystals in which the polymer crystal has a number density of 40 μm ⁻³ or more has not been obtained.

At this time, the polymer melt is preferably a general-purpose plastic melt, more preferably a polypropylene melt, and further preferably an isotactic polypropylene melt. General-purpose plastic polymer oriented crystals and polypropylene polymer oriented crystals have improved properties such as heat resistance and mechanical strength, and the crystal molecule size is on the order of nanometers. high. Here, “mechanical strength” means total strength such as breaking strength, rigidity and toughness. Further, isotactic polypropylene in which methyl groups are arranged in the same direction is preferable because the crystallinity is further improved and the above-described physical properties are remarkably improved. Therefore, general-purpose plastics such as polypropylene should be applied to various industrial parts such as automobiles and electrical products that could not be applied due to insufficient mechanical strength and heat resistance. And the cost of the industrial parts can be significantly reduced. In addition, as described above, since PP is easy to recycle monomers, it can reduce the amount of fossil fuel used and contribute to CO ₂ reduction, which is a global issue.

  The present invention also includes an extrusion molded body, an injection molded body, and a blow molded body of the polymer crystal. Here, the “extruded molded product” is a molded product obtained by a publicly known extrusion molding method, the “injected molded product” is a molded product obtained by a publicly known injection molding, and the “blow molded product” is itself It means a molded body obtained by publicly known blow molding.

  Further, the present invention provides a polymer melt containing 0.1 to 0.5% by weight of a nucleating agent having a number average particle size of 0.1 μm or less at a strain rate equal to or higher than a critical elongation strain rate. Also included is a method for producing a polymer crystal, which includes an alignment melt crystallization step for bringing the melt into an oriented melt state, and a rapid crystallization step for cooling crystallization while maintaining the orientation melt state of the polymer melt. To do. The polymer melt is preferably a general-purpose plastic melt, more preferably a polypropylene melt, and further preferably an isotactic polypropylene melt.

  As described above, according to the present invention, it is possible to provide a polymer crystal body, particularly a bulk molded body, having excellent properties such as mechanical strength, heat resistance, and transparency. Therefore, general-purpose plastic can be used as an alternative to engineering plastic, and the cost of various industrial products made of polymer can be greatly reduced. Moreover, since it is possible to make the polymer the same strength as that of the metal, it is possible to use the bulk molded body of the polymer crystal as an alternative to the metal. If the metal can be substituted, the specific gravity is very light, 1/8 that of metal. For example, if it is used as an interior / exterior material for a vehicle, the weight of the vehicle can be reduced to a fraction and the fuel consumption can be greatly reduced. Therefore, the present invention can contribute to significant energy saving.

  An embodiment of the present invention will be described as follows. However, the present invention is not limited to this, and can be implemented in a mode in which various modifications are made within the described range. Moreover, all the academic literatures and patent literatures described in this specification are incorporated herein by reference.

<1. Polymer Crystalline According to the Present Invention>
The polymer crystal according to the present invention is a polymer crystal containing a polymer crystal and a nucleating agent, characterized by satisfying the following conditions (I), (II) and (III): Is. (I) contains 0.1 to 0.5% by weight of nucleating agent;
(II) The crystallinity of the polymer crystal is 70% or more;
(III) The size of the polymer crystal is 300 nm or less.

Here, since the crystal size D ⁻³ = number density ν (μm ⁻³ ), the polymer crystal according to the present invention is a polymer crystal containing a polymer crystal and a nucleating agent, It can also be expressed as satisfying the conditions of (I), (II) and (III ′).
(I) contains 0.1 to 0.5% by weight of nucleating agent;
(II) The crystallinity of the polymer crystal is 70% or more;
(III ′) The number density of the polymer crystals is 40 μm ⁻³ or more.

  The polymer is not particularly limited, and even a so-called general-purpose plastic such as polyethylene (PE), polypropylene (PP), polystyrene (PS), polyethylene terephthalate (PET), nylon, Teflon (registered trademark), etc. So-called engineering plastics such as fluororesin may be used. If it can be used as an alternative to engineering plastics by improving the mechanical properties, heat resistance, transparency, etc. of inexpensive general-purpose plastics, the cost of resin-made industrial parts will be greatly reduced. Can do. Therefore, it is preferable to apply a general-purpose plastic to the manufacturing method of the present invention. Furthermore, PP is preferable among general-purpose plastics. This is because PP has preferable characteristics such as high heat resistance and high mechanical strength compared to other general-purpose plastics. Of PP, isotactic polypropylene (hereinafter referred to as “iPP” where appropriate) is particularly preferred. This is because isotactic polypropylene has a structure in which methyl groups are arranged in the same direction, so that it has good crystallinity and a polymer oriented crystal is easily obtained. In addition, it is possible to obtain a polymer oriented crystal having higher transparency because the crystal molecules of the obtained polymer oriented crystal are likely to be finer than ordinary PP. The polymer may be composed of a single polymer or a mixture of a plurality of types of polymers. For example, PP, PE, polybutene 1 and the like can be appropriately combined. By combining a plurality of types of polymers, the physical properties of one polymer can be compensated for by the physical properties of the other polymer. What is necessary is just to set the mixing ratio of a polymer | macromolecule suitably according to the objective.

  Moreover, the said polymer | macromolecule in this invention can be specified as follows. That is, the polymer is not particularly limited as long as it is a crystalline resin. For example, low density polyethylene, linear low density polyethylene, high density polyethylene, isotactic polypropylene, syndiotactic polypropylene, hemiisotactic. Α-olefin heavy such as tic polypropylene, cycloolefin polymer, stereoblock polypropylene, polybutene-1, poly-3-methyl-1-butene, poly-3-methyl-1-pentene, poly-4-methyl-1-pentene Polyolefin polymers such as α-olefin copolymers such as polymers, ethylene / propylene blocks or random copolymers; Thermoplastic linear polyester polymers such as polyethylene terephthalate, polybutylene terephthalate, polyhexamethylene terephthalate; Polysulfide polymers such as phenylene sulfide; aliphatic hydroxycarboxylic acid polymers such as polylactic acid and polycaprolactone; linear polyamide polymers such as polyhexamethylene adipamide; crystalline polystyrene polymers such as syndiotactic polystyrene; Examples thereof include condensation polymers such as polyimide, polyamideimide, acrylic acid, methacrylic acid, and nylon.

  Among the above crystalline resins, polyolefin resins that have a remarkable effect of using the nucleating agent used in the present invention are suitable, such as polypropylene, ethylene / propylene block or random copolymer, and α-olefin / propylene other than ethylene. Polypropylene resins such as block or random copolymers and mixtures of these propylene polymers with other α-olefin polymers, and polyethylene are particularly suitable.

  The polymer crystal according to the present invention contains a fine nucleating agent (referred to as “nanonucleating agent”) having a number average particle size of 0.1 μm or less (more preferably 50 nm or less). By using a nucleating agent that satisfies the above condition of the number average particle diameter, the surface area of the nucleating agent is increased, and a nucleation effect can be sufficiently obtained. Accordingly, the crystallinity of the polymer crystal is remarkably improved, and a polymer crystal having excellent properties such as mechanical strength, heat resistance, and transparency can be obtained. Therefore, according to the present invention, a bulk molded body of polymer crystals having a certain thickness or more can be obtained. Here, the bulk body refers to a molded body having a thickness of 1 mm or more. Here, the “thickness” in the molded body refers to the size of the thinnest part in the molded body. In addition, a sheet-like thing is also contained in a bulk molded object.

  In addition, the said number average particle diameter is defined by following Numerical formula (1).

(In the formula, x is the particle size, and f (x) is the number distribution function of the particle size.)
The number average particle diameter can be measured according to the description in “Polymer Journal, Vol. 39, No. 1, pp55-64 (2007)”. Briefly, the number average particle size is determined by measuring the particle size of the nucleating agent with a small angle X-ray scattering method (SAXS method), a scanning electron microscope (SEM), a transmission electron microscope (TEM), or the like. Can do. The “particle diameter” is intended to be the diameter of the circle when the particle shape is substantially circular, and is intended to be the major axis of the ellipse when it is substantially elliptical. Is intended to be the length of the side of the square, and if it is substantially rectangular, the length of the long side of the rectangle is intended.

  Here, in general, the “nucleating agent” refers to a substance that can improve the crystallinity of the polymer crystal when it is contained. In addition, the substance used as the nucleating agent needs to be a substance that does not melt (or hardly melts) at the crystallization temperature of the polymer. The polymer crystal according to the present invention contains a nucleating agent. By containing the nucleating agent in this manner, the crystal particles are refined even in the bulk molded body, and the crystallization speed is improved to enable high-speed molding. As the nucleating agent, a nucleating agent composed of a compound represented by the following general formula (1) can be preferably used.

(Wherein R ¹ is oxygen, sulfur or a hydrocarbon group having 1 to 10 carbon atoms, R ² and R ³ are hydrogen or a hydrocarbon group having 1 to 10 carbon atoms, and R ² and R ³ are the same kind. may be heterologous even, R ² to each other, may have a ring by bonding with R ³ s or R ² and R ^3, M is a monovalent to trivalent metal atom, n Is an integer from 1 to 3.)
Specifically, sodium-2,2′-methylene-bis (4,6-di-t-butylphenyl) phosphate, sodium-2,2′-ethylidene-bis (4,6-di-t-butyl) Phenyl) phosphate, lithium-2,2'-methylene-bis- (4,6-di-t-butylphenyl) phosphate, lithium-2,2'-ethylidene-bis (4,6-di-t- Butylphenyl) phosphate, sodium-2,2'-ethylidene-bis (4-i-propyl-6-t-butylphenyl) phosphate, lithium-2,2'-methylene-bis (4-methyl-6- t-butylphenyl) phosphate, lithium-2,2'-methylene-bis (4-ethyl-6-t-butylphenyl) phosphate, calcium-bis [2,2'-thiobis (4-methyl-6- t-butylphenyl) phosphate], calcium-bis [2,2'-thiobis (4-ethyl-6-t-butylphenyl) phosphate], calcium-bis [2,2 '-Thiobis- (4,6-di-t-butylphenyl) phosphate], magnesium-bis [2,2'-thiobis (4,6-di-t-butylphenyl) phosphate], magnesium-bis [ 2,2'-thiobis- (4-t-octylphenyl) phosphate], sodium-2,2'-butylidene-bis (4,6-di-methylphenyl) phosphate, sodium-2,2'-butylidene -Bis (4,6-di-t-butylphenyl) phosphate, sodium-2,2'-t-octylmethylene-bis (4,6-di-methylphenyl) phosphate, sodium-2,2'- t-octylmethylene-bis (4,6-di-t-butylphenyl) phosphate, calcium-bis- (2,2'-methylene-bis (4,6-di-t-butylphenyl) phosphate), Magnesium-bis [2,2'-methylene-bis (4,6-di-t-butylphenyl) phosphate], barium-bis [2,2'-methylene -Bis (4,6-di-t-butylphenyl) phosphate], sodium-2,2'-methylene-bis (4-methyl-6-t-butylphenyl) phosphate, sodium-2,2'- Methylene-bis (4-ethyl-6-t-butylphenyl) phosphate, sodium (4,4'-dimethyl-5,6'-di-t-butyl-2,2'-biphenyl) phosphate, calcium Bis [(4,4'-dimethyl-6,6'-di-t-butyl-2,2'-biphenyl) phosphate], sodium-2,2'-ethylidene-bis (4-m-butyl-6 -t-Butylphenyl) phosphate, sodium-2,2'-methylene-bis (4,6-di-methylphenyl) phosphate, sodium-2,2'-methylene-bis (4,6-di-ethyl) Phenyl) phosphate, potassium-2,2'-ethylidene-bis (4,6-di-t-butylphenyl) phosphate, calcium-bis [2,2'-ethylidene-bis (4,6-di-t) -Butylpheny Phosphate], magnesium-bis [2,2'-ethylidene-bis (4,6-di-t-butylphenyl) phosphate], barium-bis [2,2'-ethylidene-bis (4,6- Di-t-butylphenyl) phosphate], aluminum-tris [2,2'-methylene-bis (4,6-di-t-butylfell) phosphate] and aluminum-tris [2,2'-ethylidene-bis (4,6-di-t-butylphenyl) phosphate], and mixtures of two or more thereof.

  Of the above, sodium-2,2′-methylene-bis (4,6-di-t-butylphenyl) phosphate is particularly preferred.

  Moreover, in this invention, the nucleating agent which consists of a compound shown by following General formula (2) can also be used preferably.

(In the formula, R ⁴ is hydrogen or a hydrocarbon group having 1 to 10 carbon atoms, M is a 1 to 3 valent metal atom, and n is an integer of 1 to 3).
Specifically, sodium-bis (4-t-butylphenyl) phosphate, sodium-bis (4-methylphenyl) phosphate, sodium-bis (4-ethylphenyl) phosphate, sodium-bis (4-i -Propylphenyl) phosphate, sodium-bis (4-t-octylphenyl) phosphate, potassium-bis (4-t-butylphenyl) phosphate, calcium-bis (4-t-butylphenyl) phosphate, magnesium -Bis (4-t-butylphenyl) phosphate, lithium-bis (4-t-butylphenyl) phosphate, aluminum-bis (4-t-butylphenyl) phosphate, and mixtures of two or more of these Can be mentioned.

  Of the above, sodium-bis (4-t-butylphenyl) phosphate is particularly preferred.

  In the present invention, a nucleating agent comprising a compound represented by the following general formula (3) can also be preferably used.

(In the formula, R ⁵ is hydrogen or a hydrocarbon group having 1 to 10 carbon atoms.)
Specifically, 1,3,2,4-dibenzylidene sorbitol, 1,3-benzylidene-2,4-p-methylbenzylidene sorbitol, 1,3-benzylidene-2,4-p-ethylbenzylidene sorbitol, 1 , 3-p-methylbenzylidene-2.4-benzylidene sorbitol, 1,3-p-ethylbenzylidene-2,4-benzylidene sorbitol, 1,3-p-methylbenzylidene-2,4-p-ethylbenzylidene sorbitol, 1, 3-p-Ethylbenzylidene-2,4-p-methylbenzylidenesorbitol, 1,3,2,4-di (p-methylbenzylidene) sorbitol, 1,3,2,4-di (p-ethylbenzylidene) sorbitol 1,3,2,4-di (pn-propylbenzylidene) sorbitol, 1,3,2,4-di (pi-propylbenzylidene) sorbitol, 1,3,2,4-di (pn-butylbenzylidene) Sorbitol, 1,3,2,4-di (ps-butylbenzylidene) sorbitol, 1,3,2,4-di (pt-butylbenzyl) Den) sorbitol, 1,3,2,4-di (2 ', 4'-dimethylbenzylidene) sorbitol, 1,3,2,4-di (p-methoxybenzylidene) sorbitol, 1,3,2,4- Di (p-ethoxybenzylidene) sorbitol, 1,3-benzylidene-2-4-p-chlorobenzylidene sorbitol, 1,3-p-chlorobenzylidene-2,4-benzylidenesorbitol, 1,3-p-chlorobenzylidene- 2,4-p-methylbenzylidene sorbitol, 1,3-p-chlorobenzylidene-2,4-p-ethylbenzylidene sorbitol, 1,3-p-methylbenzylidene-2,4-p-chlorobenzylidene sorbitol, 1, 3-p-ethylbenzylidene-2,4-p-chlorobenzylidene sorbitol and 1,3,2,4-di (p-chlorobenzylidene) sorbitol, and mixtures of two or more of these.

  Among the above, 1,3,2,4-dibenzylidene sorbitol, 1,3,2,4-di (p-methylbenzylidene) sorbitol, 1,3,2,4-di (p-ethylbenzylidene) sorbitol 1,3-p-chlorobenzylidene-2,4-p-methylbenzylidene sorbitol, 1,3,2,4-di (p-chlorobenzylidene) sorbitol, and mixtures of two or more thereof are particularly preferred.

  Further, the nucleating agent includes aromatic carboxylic acid or aliphatic carboxylic acid metal salt, for example, aluminum benzoate, aluminum pt-butylbenzoate, sodium adipate, sodium thiophenecarboxylate, pyrrole carboxylate. Examples include sodium acid. In addition, inorganic compounds such as talc described later can also be used as a nucleating agent.

  In preparing the polymer crystal of the present invention, the nucleating agent is 0.1 to 0.5% by weight, preferably 0.15 to 0.4% by weight, more preferably, based on the polymer crystal. Is preferably used in an amount of 0.2 to 0.3% by weight. When the content of the nucleating agent is within the above range, the distance between adjacent nucleating agents can be controlled to a nanometer size, and the crystal size of the polymer formed using the nucleating agent as a nucleus is also nanometer. The size can be controlled.

  The method for producing the nanonucleating agent is not particularly limited. For example, it can be produced according to the description of “Polymer Journal, Vol. 39, No. 1, pp55-64 (2007)”. In brief, the nanonucleating agent can be produced by spray drying or solution crystallization.

  The content of the nucleating agent in the polymer crystal can be determined by using a known analysis method capable of analyzing the nucleating agent.

The polymer crystal according to the present invention has a crystallinity of 70% or more, preferably 80% or more, and more preferably 90% or more. Here, “the degree of crystallinity of the polymer crystal” means the ratio of the crystal contained in the polymer crystal. The crystallinity of the polymer crystal can be examined by a known method. For example, crystallinity can be determined by density method using water and ethyl alcohol (see LE Alexander, “X-ray diffraction of polymer (top)”, Kagaku Dojin, 1973, p.171. ) The crystallinity χ _c of the polymer crystal is obtained by the following mathematical formula (2).

In the above formula, ρ represents the crystal density of the sample, ρ _a represents the amorphous density, and ρ _c represents the crystal density. Also, literature values are available for ρ _a and ρ _c (see Qirk RP and Alsamarriaie MAA, Awiley-interscience publication, New York, Polymer Handbook, 1989). For example, according to Polymer Handbook, the crystal density and amorphous density of iPP are ρ _a = 0.855 (g / cm ³ ) and ρ _c = 0.936 (g / cm ³ ), respectively.

  In the polymer crystal according to the present invention, the size of the crystal contained in the polymer crystal is 300 nm or less, preferably 100 nm or less, more preferably 20 nm or less. The size of the crystal can be examined by a known X-ray scattering method. The X-ray scattering method can be performed by, for example, a small angle X-ray scattering method (SAXS method). Experimental facilities that can perform X-ray scattering are, for example, the X-ray small-angle scattering system installed at the University of Hiroshima University Industry-Academia Collaboration Center VBL, the High-Intensity Light Science Research Center (JASRI) SPring-8, the beamline BL40B2, Energy Science Laboratory (KEK) Photon Factory (PF), Beamline BL10C and so on. The wavelength of the X-ray used for detection is, for example, 0.1 nm or 0.15 nm. As the detector, an imaging plate (Imaging Plate), a position sensitive detector (PSPC), or the like can be used.

In addition, the peak of the small angle (q) Å ⁻¹ -X-ray scattering intensity (I _x ) curve in the SAXS method is the closest distance between microcrystals when the average size D microcrystals are randomly packed together (= (Reference: A. Guinier, “Theory and practice of X-ray crystallography”, Rigaku Denki, p513, 1967)), the crystal size D can be obtained from the Bragg equation. .
Bragg's formula: D = 2π ÷ q
The polymer crystal according to the present invention has a crystal number density of 40 μm ⁻³ or more, preferably 10 ³ μm ⁻³ or more, more preferably 10 ⁵ μm ⁻³ or more. is there. The number density ν can be obtained by the following equation.
(Formula) Number density ν (μm ⁻³ ) = crystal size D ⁻³
According to Hall-Petch's law, it is known that the strength of the crystal increases in proportion to the inverse of the square root of the crystal size D, so that the strength of the polymer crystal according to the present invention is remarkably improved. Can be easily understood. For example, when the crystal size D is changed from 1 μm to 10 nm, √100 = 10 times the intensity.

  The polymer crystal according to the present invention is not limited as long as it contains polymer crystals, and may contain not only crystals but also amorphous.

  The polymer crystal according to the present invention may contain other additives. Other additives that may be contained in the polymer crystal according to the present invention include antioxidants, hydrochloric acid absorbents, heat stabilizers, weathering stabilizers, light stabilizers, ultraviolet absorbers, slip agents, Blocking agents, antifogging agents, lubricants, antistatic agents, flame retardants, pigments, dyes, dispersants, copper damage inhibitors, neutralizing agents, foaming agents, plasticizers, antifoaming agents, crosslinking agents, peroxides, etc. Examples thereof include a flow improver, a weld strength improver, a natural oil, a synthetic oil, and a wax.

  Moreover, as antioxidant, a phenolic antioxidant, sulfur type antioxidant, phosphorus antioxidant, etc. can be used.

  Examples of phenolic antioxidants include 2,6-di-tert-butyl-p-cresol (= 3,5-di-tert-butyl-4-hydroxytoluene), stearyl (3,3-dimethyl-4 -Hydroxybenzyl) thioglycolate, stearyl-β- (4-hydroxy-3,5-di-tert-butylphenol) propionate, distearyl-3,5-di-tert-butyl-4-hydroxybenzylphosphonate, 2, 4,6-tris (3 ', 5'-di-tert-butyl-4'-hydroxybenzylthio) -1,3,5-triazine, distearyl (4-hydroxy-3-methyl-5-tert-butyl Benzyl) malonate, 2,2′-methylenebis (4-methyl-6-tert-butylphenol), 4,4′-methylenebis (2,6-di-tert-butylphenol), 2,2′-methylenebis [6- ( 1-methylcyclohexyl) p-cresol], bis [3,5-bis [4-hydroxy-3-tert-butylphenyl) butyric acid] glyce Cole ester, 4,4'-butylidenebis (6-tert-butyl-m-cresol), 1,1,3-tris (2-methyl-4-hydroxy-5-tert-butylphenyl) butane, bis [2- tert-butyl-4-methyl-6- (2-hydroxy-3-tert-butyl-5-methylbenzyl) phenyl] terephthalate, 1,3,5-tris (2,6-dimethyl-3-hydroxy-4-phenyl) tert-butyl) benzyl isocyanurate, 1,3,5-tris (3,5-di-tert-butyl-4-hydroxybenzyl) -2,4,6-trimethylbenzene, tetrakis [methylene-3- (3, 5-Di-tert-butyl-4-hydroxyphenyl) propionate] methane, 1,3,5-tris (3,5-di-tert-butyl-4-hydroxybenzyl) isocyanurate, 1,3,5-tris [(3,5-di-tert-butyl-4-hydroxyphenyl) propionyloxyethyl] isocyanurate, 2-octylthio-4,6-di (4-hydroxy-3,5-di-tert-butyl) pheno Phenolic compounds such as xyl-1,3,5-triazine, 4,4'-thiobis (6-tert-butyl-m-cresol) and 4,4'-butylidenebis (2-tert-butyl-5-methylphenol) Polyhydric phenol carbonic acid oligoesters such as carbonic acid oligoesters (for example, polymerization degree 2 to 10).

  Examples of the sulfur-based antioxidant include dialkylthiodipropionates such as dilauryl-, dimyristyl-, distearyl- and polyhydric alcohols of alkylthiopropionic acid such as butyl-, octyl-, lauryl-, stearyl- (for example, Examples include esters of glycerin, trimethylolethane, trimethylolpropane, pentaerythritol, trishydroxyethyl isocyanurate) (for example, pentaerythritol tetralauryl thiopropionate).

  Examples of phosphorus antioxidants include trioctyl phosphite, trilauryl phosphite, tridecyl phosphite, octyl-diphenyl phosphite, tris (2,4-di-tert-butylphenyl) phosphite, triphenyl Phosphite, tris (butoxyethyl) phosphite, tris (nonylphenyl) phosphite, distearylpentaerythritol diphosphite, tetra (tridecyl) -1,1,3-tris (2-methyl-5-tert-butyl- 4-hydroxyphenyl) butanediphosphite, tetra (C12-C15 mixed alkyl) -4,4'-isopropylidenediphenyldiphosphite, tetra (tridecyl) -4,4'-butylidenebis (3-methyl-6-tert -Butylphenol) diphosphite, tris (3,5-di-tert-butyl-4-hydroxyphenyl) phosphite, tris Di-mixed nonylphenyl) phosphite, hydrogenated-4,4'-isopropylidenediphenol polyphosphite, bis (octylphenyl) bis [4,4'-butylidenebis (3-methyl-6-tert-butylphenol) )], 1,6-hexanediol diphosphite, phenyl, 4,4'-isopropylidenediphenol, pentaerythritol diphosphite, bis (2,4-di-tert-butylphenyl) pentaerythritol diphosphite, Bis (2,6-di-tert-butyl-4-methylphenyl) pentaerythritol diphosphite, tris [4,4′-isopropylidenebis (2-tert-butylphenol)] phosphite, phenyl diisodecyl phosphite, Di (nonylphenyl) pentaerythritol diphosphite), tris (1,3-di-stearoyloxyisopropyl) phosphite, 4,4'- Sopropylidenebis (2-tert-butylphenol) di (nonylphenyl) phosphite, 9,10-di-hydro-9-oxa-9-oxa-10-phosphaphenanthrene-10-oxide, tetrakis ( 2,4-di-tert-butylphenyl) -4,4′-biphenylenediphosphonite.

  Further, as other antioxidants, 6-hydroxychroman derivatives such as various tocopherols of α, β, γ, and δ or mixtures thereof, 2- (4-methyl-pent-3-enyl) -6-hydroxychroman 2 , 5-dimethyl-substituted, 2,5,8-trimethyl-substituted, 2,5,7,8-tetramethyl-substituted, 2,2,7-trimethyl-5-tert-butyl-6-hydroxychroman, 2 , 2,5-Trimethyl-7-tert-butyl-6-hydroxychroman, 2,2,5-trimethyl-6-tert-butyl-6-hydroxychroman, 2,2'-dimethyl-5-tert-butyl- 6-hydroxychroman and the like can also be used.

The polymer crystal according to the present invention is
Formula _{(4) M a Al y (} OH) 2x + 3y-2z (A) z · aH 2 O ··· (4)
(M is Mg, Ca or Zn, A is an anion other than a hydroxyl group, x, y, z are positive numbers, and a is 0 or positive number), for example,
Mg ₆ Al ₂ (OH) ₁₆ CO ₃ .4H ₂ O,
Mg ₅ Al ₂ (OH) ₁₄ CO ₃ .4H ₂ O,
_{Mg 10 Al 2 (OH) 22} (CO 3) 2 · 4H 2 O,
_{Mg 6 Al 2 (OH) 16} HPO 4 · 4H 2 O,
Ca ₆ Al ₂ (OH) ₁₆ CO ₃ .4H ₂ O,
Zn ₆ Al ₂ (OH) ₁₆ CO ₃ .4H ₂ O,
_{Zn 6 Al 2 (OH) 16} SO 4 · 4H 2 O,
Mg ₆ Al ₂ (OH) ₁₆ SO ₃ .4H ₂ O or the like may be contained as a hydrochloric acid absorbent.

  Examples of the light stabilizer that can be contained in the polymer crystal according to the present invention include 2-hydroxy-4-methoxybenzophenone, 2-hydroxy-4-n-octoxybenzophenone-2,2′-di-hydroxy. -4-methoxybenzophenone, hydroxybenzophenones such as 2,4-dihydroxybenzophenone, 2- (2'-hydroxy-3'-tert-butyl-5'-methylphenyl) -5-chlorobenzotriazole, 2- (2 '-Hydroxy-3', 5'-di-tert-butylphenyl) -5-chlorobenzotriazole, 2- (2'-hydroxy-5'-methylphenyl) benzotriazole, 2- (2'-hydroxy-3 Benzotriazoles such as', 5'-di-tert-amylphenyl) benzotriazole, phenyl salicylate, p-tert-butylphenyl salicylate, 2,4-di-tert-butylphenyl-3,5-di-tert- Butyl-4-hydroxybenzoate, hexadecyl- Benzoates such as 3,5-di-tert-butyl-4-hydroxybenzoate, 2,2'-thiobis (4-tert-octylphenol) Ni salt, [2,2'-thiobis (4-tert-octylphenolate) )]-N-butylamine Ni, nickel compounds such as (3,5-di-tert-butyl-4-hydroxybenzyl) phosphonic acid monoethyl ester Ni salt, α-cyano-β-methyl-β- (p- Methoxyphenyl) substituted acrylonitriles such as methyl acrylate and N'-2-ethylphenyl-N-ethoxy-5-tert-butylphenyl oxalic acid diamide, N-2-ethylphenyl-N'-2-ethoxyphenyl oxalic acid Oxalic acid dianilides such as diamide, bis (2,2,6,6-tetramethyl-4-piperidine) sebacate, poly [{(6- (1,1,3,3-tetramethylbutyl) imino} -1 , 3,5-Triazine-2,4-diyl {4- (2,2,6,6-tetramethylpiperidyl) imino Hexamethylene], hindered amine compounds such as 2- (4-hydroxy-2,2,6,6-tetramethyl-1-piperidyl) condensates of ethanol and dimethyl succinate, and the like.

  Examples of the lubricant that can be included in the polymer crystal according to the present invention include aliphatic hydrocarbons such as paraffin wax, polyethylene wax, and polypropylene wax, caprins, lauric acid, myristic acid, palmitic acid, margaric acid, Higher fatty acids such as stearic acid, arachidic acid, and behenic acid or their metal salts (for example, lithium salt, calcium salt, sodium salt, magnesium salt, potassium salt), aliphatic such as palmityl alcohol, cetyl alcohol, stearyl alcohol Alcohols, capronic amides, caprylic acid amides, capric acid amides, lauric acid amides, myristic acid amides, palmitic acid amides, stearic acid amides and other aliphatic amides, aliphatic and alcohol esters, fluoroalkyl carbonates Bon acid or metal salts, fluorine compounds such as perfluoroalkyl sulfonic acid metal salts.

  The additive as described above is used in an amount of 0.0001 to 10 parts by weight with respect to 100 parts by weight of the polymer crystal.

  The polymer crystal according to the present invention may contain an inorganic filler. Specific examples of inorganic fillers include fine talc, kaolinite, calcined clay, vilophyllite, sericite, wollastonite and other natural silicic acid or silicates, precipitated calcium carbonate, heavy calcium carbonate, magnesium carbonate, etc. Synthetic silicic acid such as carbonates, hydroxides such as aluminum hydroxide, magnesium hydroxide, oxides such as zinc oxide, zinc white, magnesium oxide, barium sulfate, hydrous calcium silicate, hydrous aluminum silicate, hydrous silicic acid, anhydrous silicic acid or the like Powdered filler such as silicate, flake filler such as mica, glass fiber, basic magnesium sulfate whisker, calcium titanate whisker, aluminum borate whisker, sepiolite, PMF (Processed Mineral Fiber), zonotlite, potassium titanate , Elestadite Possible of the fibrous filler, Garasubarun, be used as the balloon-shaped fillers such as fly ash balloon.

  Of these, talc, calcium carbonate, glass fiber, potassium titanate, barium sulfate and the like may be blended in the polymer crystal according to the present invention, and usually a fine powder having an average particle size of 0.01 to 10 μm. Talc is preferably used.

  The average particle size of talc can be measured by a liquid phase precipitation method.

  In addition, the inorganic filler used in the polymer crystal according to the present invention, particularly talc, may be untreated or may be surface-treated in advance. As an example of this surface treatment, specifically, a chemical or physical treatment using a treatment agent such as a silane coupling agent, a higher fatty acid, a fatty acid metal salt, an unsaturated organic acid, an organic titanate, a resin acid, or polyethylene glycol. Is mentioned. When talc subjected to such surface treatment is used, a polymer crystal having excellent weld strength, paintability, and moldability can be obtained. Two or more kinds of such inorganic fillers may be used in combination.

  In addition to such inorganic fillers, organic fillers such as high styrenes, lignin, and re-rubber can also be used in the polymer crystal according to the present invention.

  The polymer crystal according to the present invention further improves the balance of physical properties, durability, paintability, printability, scratch resistance, molding processability, and the like by containing the additives, fillers and the like as described above. A molded body can be formed.

  The polymer crystal of the present invention is kneaded into the polymer crystal of the present invention by using the method for producing a polymer crystal disclosed in the present invention, such as additives and inorganic fillers. Can be manufactured.

<2. Production method of polymer crystal according to the present invention>
As one aspect of the method for producing a polymer crystal according to the present invention described above, a method for producing a polymer oriented crystal uniquely developed by the present inventors will be described, but the present invention is limited to this. It is not a thing.

One aspect of the method for producing a polymer crystal according to the present invention is a polymer melt (“nanonuclear agent high "Molecular melt") is stretched at a strain rate equal to or higher than the critical elongation strain rate to bring the polymer melt into an oriented melt state, and the oriented melt state of the polymer melt is maintained. And a rapid crystallization step of cooling and crystallizing. Moreover, the said manufacturing method may be a method including the critical elongation strain rate determination process of determining the critical elongation strain rate of a nanonucleating agent polymer melt. Here, in the critical elongation strain rate determination step, a disk-shaped nanonuclear polymer melt having a radius x ₀ and a thickness 2z ₀ is sandwiched between transparent plates, and the polymer melt is cooled to a supercooled state. The polymer melt is crushed by a transparent plate at a constant speed v in the thickness direction, and a critical point radius x ^{* at} which the polymer melt becomes an oriented crystal is measured. Ε ^* = αx ^{* 2} , where α = It may be a step of calculating a critical elongation strain rate ε ^* from an equation which is v / (2x ₀ ² z ₀ ). This is a step of measuring the critical point thickness 2z ^{* at} which the polymer melt becomes an oriented crystal and calculating the critical elongation strain rate ε ^* from the equation, ε ^* = (v / 2) z ^{* -1.} May be.

The critical elongation strain rate determination step has a center distance x ′ ₀ and a thickness 2z ₀ , sandwiches a plate-shaped nano-nucleating agent polymer melt having a constant width between transparent plates, and cools the polymer melt. Then, the polymer melt is brought into a supercooled state, and the polymer melt is crushed with a transparent plate at a constant speed v in the thickness direction, the critical point center distance x ′ ^{* at} which the polymer melt becomes an oriented crystal is measured, and ε ^* = Αx ′ ^* , where α = v / (x ′ ₀ z ₀ ), and the critical elongation strain rate ε ^* may be calculated from the equation.

  Nucleation is achieved by crystallizing an oriented polymer melt containing a predetermined amount of the above-mentioned nanonucleating agent while maintaining the state of the oriented melt, compared to an oriented melt containing no nanonucleating agent. Efficiency is improved. Thereby, the crystallization efficiency of the polymer is improved, and a polymer crystal having a high degree of crystallization can be easily obtained. In addition, according to the above method, a bulk molded body of polymer crystals having a certain upper thickness can be obtained.

  Usually, the molecular chain of the polymer present in the polymer melt exists in a disordered and isotropic form (for example, a string shape (random coil)). The polymer melt in such a state is called “isotropic melt” or “Isotropic melt”. When an external field such as shear or elongation is applied to the isotropic melt, the molecular chain of the polymer is elongated, but entropy relaxation occurs due to the thermodynamic law, and the molecular chain is originally disordered. Trying to return to the correct state. When an external field exceeding a certain strain rate is applied, the molecular chain overcomes the entropy relaxation that tries to return to the original disordered state, and the molecular chain has a high orientation order melt ("alignment melt" or "Oriented melt"). The strain rate that can overcome the entropy relaxation and can turn the polymer isotropic melt into the oriented melt is called “critical strain rate”. In particular, the critical strain rate at which a polymer melt can be stretched into a bulk oriented melt is referred to as “critical elongation strain rate”.

  Therefore, in order to produce a polymer oriented crystal, it is necessary to first stretch the polymer melt at a strain rate equal to or higher than the critical elongation strain rate. However, until now, a method and means for determining the critical elongation strain rate have not been established. The “critical elongation strain rate determination step” that can determine the critical elongation strain rate of the polymer melt, which is preferably included in the method for producing a polymer oriented crystal, will be described below. Note that the method for producing a polymer oriented crystal may be an embodiment in which the “critical elongation strain rate determination step” is included or may not be included.

  The nano nucleating agent polymer melt is obtained by dispersing a nucleating agent having a number average particle size of 0.1 μm or less in the polymer melt. The specific method is not particularly limited, and a preferable method can be appropriately employed depending on the nanonucleating agent and the polymer material. The method for obtaining a nanonuclear polymer melt when a polyolefin resin is used as the polymer is described below in accordance with the description in “Polymer Journal, Vol. 39, No. 1, pp55-64 (2007)”. However, the present invention is not limited to this.

  The organic acid metal salt shown in the section of “1. Polymer crystal according to the present invention” was dissolved in an alcohol solvent, and further an aromatic solvent was added and heated, and further a polyolefin resin was added and dissolved. After cooling, an organic acid metal salt (= nanonuclear agent) is deposited. Since the organic acid metal salt exhibits higher solubility at a low temperature in an alcohol-based solvent, the concentration is preferably close to the saturation concentration at the temperature at which the polyolefin resin is heated and dissolved. If the concentration is much higher than the saturation concentration, the number average particle diameter of the organic acid metal salt exceeds 0.1 μm, and it does not become a nanonucleating agent. Examples of the alcohol solvent include methanol, ethanol, propanol, isopropanol, butanol, tert-butanol, pentanol, and hexanol. Butanol is particularly preferred because it can be heated to a higher temperature to dissolve the polyolefin resin in the aromatic solvent and is excellent in the solubility of the organic acid metal salt. On the other hand, as the aromatic solvent, benzene, toluene, xylene, ethylbenzene, an industrial mixed solvent, or the like is used. Xylene is particularly preferable from the viewpoints of solubility of the polyolefin resin, ease of solvent removal, and safety.

(2-1: Critical elongation strain rate determination step)
The present inventors independently developed a compression-type crystallization apparatus (hereinafter referred to as “crystallization apparatus” as appropriate) that can determine the critical elongation strain rate. With such a crystallization apparatus, it has become possible to directly observe the extension crystallization of the polymer melt with an optical microscope. The configuration of the crystallization apparatus will be described with reference to the schematic diagram of FIG. The crystallization apparatus 10 is composed of a pair of transparent plates (upper transparent plate 1 and lower transparent plate 2), and the transparent plate can be controlled to a desired temperature by temperature control means (not shown). Yes. The transparent plate is not particularly limited as long as the material constituting the transparent plate is a plate-like body having such transparency that a polymer sample sandwiched between the transparent plates can be observed with an optical microscope. However, since it is necessary to sandwich the high-temperature nano-nucleating agent polymer melt, the transparent plate is preferably a material having high heat resistance, such as glass, quartz, sapphire, or diamond. The surface of the transparent plate is preferably a flat surface.

  Next, a method for determining the critical elongation strain rate of the nanonuclear polymer melt using the crystallization apparatus 10 will be described. First, a disk-shaped nanonuclear polymer melt (sample) 3 'is placed on the lower transparent plate 2, and the sample is further sandwiched between the upper transparent plate 1 and the lower transparent plate 2, and set in a polarizing microscope. Observe the crystallization process directly. Next, the sample is rapidly cooled (cooling rate: 30 ° C./min or more), the nano nucleating agent polymer melt (sample) is kept at a constant temperature (crystallization temperature) and kept in a supercooled state (supercooling degree) ΔT: 20K or more). Next, by moving the upper transparent plate 1 to the lower transparent plate 2 side at a constant speed (speed: 0 to 70 mm / s or more), the nano nucleating agent polymer melt (sample) 3 ′ is constant in the thickness direction. Crush at a speed (in this case, the lower transparent plate 2 side may be moved to the upper transparent plate 1). Of the crystallized nano nucleating agent polymer melt (sample) 3, whether or not the nano nucleating agent polymer melt becomes an oriented melt and becomes a polymer oriented crystalline material is measured, for example, by measuring the crystal size D above. If it is 300 nm or less, it can be determined that it is a polymer oriented crystal, and if it exceeds 300 nm, it can be determined that it is not a polymer oriented crystal. In other words, the critical point at which the nanonuclear polymer melt becomes an oriented crystal is determined based on the examination result of the crystal size D.

  The method for determining the critical elongation strain rate of the nanonuclear polymer melt will be described in more detail with reference to FIG. A nano nucleating agent polymer melt 3 ′ indicated by a broken line in FIG. 1 is a nano nucleating agent polymer melt before being crushed by a transparent plate (upper transparent plate 1 and lower transparent plate 2). On the other hand, the nano nucleating agent polymer melt 3 indicated by a solid line in the figure shows the nano nucleating agent polymer melt after being crushed by the transparent plates (upper transparent plate 1 and lower transparent plate 2). . In the drawing, an upper transparent plate 1 ′ indicated by a broken line indicates the upper transparent plate before crushing the polymer sample 3 ′ and its position. The center point of the disk-shaped polymer sample is indicated by “0” in the figure.

  The direction from the lower transparent plate 2 toward the upper transparent plate 1 is the thickness direction (z-axis direction in FIG. 1), and the height of the disk-shaped nanonucleating agent sandwiched between the upper transparent plate 1 and the lower transparent plate 2 is high. The distance between the transparent plates of the molecular melt 3 is defined as the thickness of the disk-shaped nanonuclear polymer melt. Further, the distance from the center of the disk made of the nano nucleating agent polymer melt 3, that is, the disk is defined as the radius.

When the nano nucleating agent polymer melt 3 ′ before being crushed is (radius, thickness) = (x ₀ , 2z ₀ ), and the nano nucleating agent polymer melt 3 ′ is crushed at a constant speed v The elongation strain rate ε (x) in
ε (x) = (dx / dt) / x (i)
Can be defined. However, in the nanonuclear polymer melt 3, (radius, thickness) = (x, 2z), and t is time.
From equation (i), v = dz / dt (ii), and volume conservation: πx ² z = πx ₀ ² z ₀ (iii)
ε (x) is
ε (x) = αx ² (iv).
Where α = v / (2z ₀ x ₀ ² ).

  Therefore, the elongation strain rate ε (x) at the radius x of the disk-shaped nanonuclear polymer melt can be calculated by the formula (iv).

Therefore, using the crystallization apparatus, as described above, the critical point (“x ^* ”) at which the nanonuclear polymer melt becomes an oriented crystal is found from the examination result of the crystal size D, and expressed in the formula (iv) By substituting, it is possible to determine the elongation strain rate ε (x ^* ) at the critical point, that is, the critical elongation strain rate ε ^* .

Also, from the above formulas (i), (ii), (iii) to ε (z)
ε (z) = (v / 2) z ⁻¹ (v).

  Therefore, the elongation strain rate ε (z) at the thickness 2z of the disk-shaped nanonuclear polymer melt can be calculated by the equation (v).

Therefore, as described above using the crystallization apparatus, the critical point (“z ^* ”) at which the nanonuclear polymer melt becomes an oriented crystal is found from the examination result of the crystal size D, and is expressed in the formula (v). By substituting, the elongation strain rate ε (z ^* ) at the critical point, that is, the critical elongation strain rate ε ^* can be determined.

In the compression-type crystallization apparatus described above, the test was performed by placing the nanonuclear polymer melt in a disk shape on the lower transparent plate 2 which is a flat plate, but the present invention is not limited to this. However, the critical elongation strain rate can be similarly determined by using a plate-like nanopolymer melt. An example of a compression type crystallization apparatus used when determining the critical elongation strain rate using a plate-like nanopolymer melt is shown in FIG. FIG. 2A is a side view of the crystallization apparatus, and FIG. 2B is a top view of the crystallization apparatus. Note that members common to those of the compression-type crystallization apparatus shown in FIG. 1 are denoted by common member numbers and description thereof is omitted. In the crystallization apparatus shown in FIG. 2, a rectangular recess having a constant length (2y ₀ ) in the width direction is provided on the lower transparent plate 2. A convex portion that fits into the concave portion is provided on the upper transparent plate 1. The nano nucleating agent polymer melt may be placed in the concave portion, and the nano nucleating agent polymer melt may be crushed by the convex portion.

  The direction from the lower transparent plate to the upper transparent plate is the thickness direction (z-axis direction in FIG. 2), and the plate-shaped nanonuclear polymer melt sandwiched between the upper transparent plate and the lower transparent plate The distance between the two transparent plates is defined as the thickness of the plate-shaped nanonuclear polymer melt. Further, when the upper and lower transparent plates are crushed, the direction in which the nanonuclear polymer melt is elongated is the longitudinal direction (x-axis direction in FIG. 2), and the direction perpendicular to the longitudinal direction and the thickness direction is the width direction ( (Y-axis direction in FIG. 2). Further, the distance from the midpoint in the longitudinal direction of the plate-like nano nucleating agent polymer melt to one end in the longitudinal direction of the nano nucleating agent polymer melt is defined as the center distance.

The nano nucleating agent polymer melt 3 ′ before being crushed is (center distance, thickness) = (x ′ ₀ , 2z ₀ ), and the nano nucleating agent polymer melt 3 after being crushed is ( Assuming that the center distance, thickness) = (x ′, 2z), the elongation strain rate ε (x ′) at the center distance x ′ when the nanonuclear polymer melt 3 ′ is crushed at a constant speed v. Is
ε (x ′) = (dx ′ / dt) / x ′ (i ′)
Can be defined.
However, the nano nucleating agent polymer melt 3 is (center distance, thickness) = (x ′, 2z), and t is time.
Equation (i), v = dz / dt (ii), and volume storage: x′yz = x ′ ₀ y ₀ z ₀ (iii ′), y = y ₀
ε (x ′) is
ε (x ′) = αx ′ ² (iv ′).
Where α = v / (2x ′ ₀ ² z ₀ ).

  Therefore, the elongation strain rate ε (x ′) at the center distance x ′ of the plate-like nanonucleating agent polymer melt can be calculated by the equation (iv ′).

Therefore, as described above, the critical point center distance (“x ′ ^* ”) at which the nanonuclear polymer melt becomes an oriented crystal is found and substituted into the mathematical formula (iv ′) to obtain the elongation strain rate at the critical point. ε (x ′ ^* ), the critical elongation strain rate ε ^* can be determined.

As explained above, when a plate-shaped nanonuclear polymer melt is used, the sample of the nanonuclear polymer melt can be extended one-dimensionally, so the above formula (iv ′) is used. Thus, the crystallization behavior of the polymer at each strain rate can be observed, and the critical elongation strain rate ε ^* can be easily determined.

(2-2: Orientation melt process)
Next, the “alignment melt process” included in the method for producing a polymer oriented crystal will be described. The "orientation melt liquefaction step", the critical elongation strain rate epsilon ^* of conditions determined in the "critical elongation strain rate epsilon ^* determination step" based on, the critical elongation strain rate nano nucleating agent polymer melt This is a step of stretching at a strain rate equal to or higher than ε ^* to bring the nanonuclear polymer melt into an oriented melt state.

In the said process, if it is the process of extending | stretching nano nucleating agent polymer melt with the strain rate more than critical elongation strain rate (epsilon) ^{*, the} extending | stretching method, the means for extending | stretching, etc. will not be specifically limited. An example of the alignment melt process will be described with reference to FIGS. However, the present invention is not limited to this. 3 and 4 are side sectional views of a die used for extrusion molding such as sheet molding and film molding of nano nucleating agent polymer melt, injection molding, blow molding and the like. When the nano nucleating agent polymer melt is discharged or injected using such a die, or the subsequent roll or mold expands the molecular chain in the nano nucleating agent polymer melt, and the critical elongation strain rate ε ^* or more By doing so, the nanonuclear polymer melt can be made into an oriented melt.

3 and 4, a plate-like (quadrangle-columnar) nanonuclear polymer melt 21 that was “length Δx ₀ , width Δy ₀ , thickness Δz ₀ ” in the die was A plate-shaped (quadrature-columnar) nanonuclear polymer having a length of Δx, a width of Δy, and a thickness of Δz immediately after crystallization, after being ejected or injected from a nozzle, or after being deformed by a roll or a mold Assuming that the melt 22 is compressed or stretched over time Δt, the elongation strain rate of the nanonuclear polymer melt is:
It can be calculated by the equation ε (β) = (β−1) ÷ Δt (vi).
Where β is a compression ratio, and β = (Δy ₀ Δz ₀ ) ÷ (ΔyΔz).

  Here, the “length” is the surface of the square columnar nano nucleating agent polymer melt, and the surfaces facing the direction of injecting the nano nucleating agent polymer melt are the bottom surface and the top surface. Is the distance between and the top surface. Also, the length of one side of the bottom or top surface that is a square is called “width”, and the length of one side orthogonal to the one side is called “thickness”.

Therefore, the “width Δy ₀ , thickness Δz ₀ ” of the nano nucleating agent polymer melt in the die is discharged or injected so that the elongation strain rate ε determined by the formula (vi) is equal to or higher than the critical elongation strain rate. Thereafter, or appropriately selecting “width Δy, thickness Δz” and Δt (time required for compression deformation) of the nanonuclear polymer melt after deformation by a roll or a mold, By performing “compression deformation”, an oriented melt can be prepared.

(2-3: Quenching crystallization process)
The “quenching crystallization process” included in the method for producing a polymer oriented crystal will be described. The “quenching crystallization step” is a step of cooling while maintaining the oriented melt state of the nanonuclear polymer melt. The rapid crystallization process causes crystallization due to nucleation and growth due to the association of molecular chains contained in the polymer oriented melt, and crystallization with a nanonucleating agent as a nucleus. Produces.

  When the polymer melt in the oriented melt state is left as it is, the entropy increases according to the thermodynamic law, and the original melt state is restored. Therefore, it can be said that it is preferable to cool and crystallize as quickly as possible in order to crystallize while maintaining the orientation melt state. Further, the temperature of the atmosphere when the polymer melt is cooled (that is, “degree of supercooling ΔT”) is not particularly limited as long as it is lower than the melting point of the polymer. In particular, since the optimum degree of supercooling varies markedly depending on the type of polymer, the optimum conditions may be adopted as appropriate. For example, in the case of polypropylene, ΔT = 20 to 60 ° C. is preferable. When the degree of supercooling is not more than the above preferable range, the crystallization rate is remarkably slowed, and the yield of the polymer oriented crystal may be lowered. On the other hand, when the degree of supercooling is not less than the above preferable range, the crystallization rate may be lowered because the diffusion of the molecular chain is delayed.

  The cooling method may be performed in the gas phase or in the liquid phase. As a cooling method, a method and means generally used in the production of polymers or a modified method thereof may be appropriately selected and employed. FIG. 5 shows a schematic diagram of an apparatus (one example) used in the method for producing a polymer oriented crystal according to the present invention. This process will be described in more detail with reference to the schematic diagram. For example, the nano nucleating agent polymer oriented melt 31 discharged or ejected from the throttle hole 32 of the die is rapidly crystallized at a desired cooling temperature. The contact with the part 33 is mentioned. As a result, the nano nucleating agent polymer oriented crystal 34 is generated after the rapid crystallization part 33. Alternatively, the nano nucleating agent polymer oriented melt 31 injected from the throttle hole 32 may be cooled by flowing into a liquid such as water having a desired cooling temperature. Further, the nano nucleating agent polymer oriented melt 31 injected from the throttle hole 32 may be exposed to an atmosphere of a desired cooling temperature. Moreover, you may cool by making the nano nucleating agent polymer oriented melt 31 inject | emitted from the aperture hole 32 contact with the roller which is desired cooling temperature. Further, when the nano nucleating agent polymer oriented melt 31 is injected from the die 33 to the mold, the mold may be cooled at a desired cooling temperature.

  In addition, the other example of the apparatus used for the manufacturing method of a polymeric oriented crystal is shown in FIG. The apparatus shown in FIG. 6 is provided with a roller 35 for pulling out the nano nucleating agent polymer oriented melt 31 in the apparatus shown in FIG. Such a roller 35 may be used to cool the nano nucleating agent polymer oriented melt 31 to a desired cooling temperature as described above.

  The polymer oriented crystal obtained as described above is a bulk molded product of polymer oriented crystals that could not be obtained so far. The bulk molded body of polymer oriented crystals includes a sparsely generated shish and kebab which is a laminated lamellar structure surrounding it, which is a conventional oriented crystal material in that it is almost entirely made of dense shish. It is different from that in which only a part is an oriented crystal, such as “incompletely oriented crystal material” and “spiral crystal” discovered by the present inventors.

  Examples of the use of the polymer oriented crystal produced as described above include the following. The polymer oriented crystal of PP can be used as the majority (90% or more) of automotive interior materials. In addition, PP polymer oriented crystals are used for interior and exterior materials of vehicles such as automobiles, airplanes, rockets, trains, ships, motorcycles, and bicycles, or parts for machine tools as substitutes for metals by taking advantage of high strength and toughness. It can be used as a mechanical member. The oriented polymer crystal can be used as a diaphragm for speakers and microphones by utilizing its high rigidity and light weight. Moreover, the polymer oriented crystal can be used as a CD or DVD as a substitute for PC by taking advantage of high transparency. Further, the polymer oriented crystal can be used as a mask for liquid crystal or plasma display by utilizing its high transparency. In addition, the polymer oriented crystal can be used as a medical article or device such as a disposable syringe, an infusion device, a drug container, etc. by utilizing its high transparency. In addition, the polymer oriented crystal can be used as a large water tank for commercial use from various bottles, glasses, and small water tanks for household use as a substitute for glass by making use of high transparency. The oriented polymer crystal can be used as a contact lens, a lens for eyeglasses, and various optical lenses by utilizing its high transparency. The oriented polymer crystal can be used as glass for buildings and houses by utilizing its high transparency. Further, the polymer oriented crystal can be used as a wide range of sports equipment such as ski shoes, skis, boards, rackets, various nets, tents, rucksacks, etc. by utilizing its high rigidity, high toughness and light weight. The oriented polymer crystals can be used as handicrafts and decorative items such as needles, scissors, and sewing machines by taking advantage of high rigidity, high toughness and light weight. Further, the polymer oriented crystal can be used as a commercial product such as a show window or a display component. The oriented polymer crystal can be used as equipment or facilities for parks, amusement parks, theme parks such as swings, seesaws, and roller coasters. In addition, the polymer oriented crystal is a structural material or box material for parts of precision equipment such as electrical / electronic / information equipment or watches; stationery such as files, folders, pencil cases, writing utensils, scissors; knives, balls, etc. Cooking utensils; packaging materials for food, sweets, tobacco, etc .; food containers, tableware, disposable chopsticks, toothpicks; furniture such as household furniture and office furniture; building materials, interior materials and exterior materials for buildings and houses; roads or Materials for bridges; materials for toys; super strong fibers and threads; fishing gear for fishing, fishing nets, fishing tools; agricultural tools, agricultural supplies; plastic bags, garbage bags; various pipes; garden supplies; and transport containers, pallets, It can be used as a box;

  On the other hand, polymer oriented crystals of PE can be used as super strength fibers or super strength yarns.

  On the other hand, fluoropolymer oriented crystals such as polyvinylidene fluoride can be used as high-precision ultrasonic elements, high-speed switching elements, high-efficiency speakers, or high-sensitivity microphones by taking advantage of high ferroelectric and piezoelectric characteristics. .

  On the other hand, the polymer oriented crystal of PET can be used as an industrial material requiring high heat resistance of about 200 ° C.

  As described above, according to the present invention, a polymer crystal can be produced. Therefore, general-purpose plastic can be used as an alternative to engineering plastic, and the cost of various industrial products made of polymer can be greatly reduced. In addition, since the polymer can be made as strong as metal, the polymer crystal can be used as a substitute for metal.

  Therefore, the present invention can be used not only in various industries that handle polymer parts, but also in all industries that handle metal parts.

It is a schematic diagram showing a compression type crystallization apparatus used for determining the critical elongation strain rate of a polymer melt. (A) is a side view of a compression crystallization apparatus, and (b) is a top view of the crystallization apparatus. It is the sectional side view seen from the y-axis direction of the die | dye (an example) used for the manufacturing method of the polymeric oriented crystal concerning this invention. It is the sectional side view seen from the z-axis direction of the die | dye (an example) used for the manufacturing method of the polymeric oriented crystal concerning this invention. It is a schematic diagram of the apparatus (an example) used for the manufacturing method of the polymer oriented crystal concerning this invention. It is a schematic diagram of the apparatus (other example) used for the manufacturing method of the polymer oriented crystal concerning this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1, 1 'upper transparent plate 2, 2' lower transparent plate 3 Nanonuclear polymer melt 10 Compression type crystallizer

Claims (23)

A polymer crystal containing a polymer crystal and a nucleating agent,
A polymer crystal characterized by satisfying the following conditions (I), (II) and (III):
(I) contains 0.1 to 0.5% by weight of nucleating agent;
(II) The crystallinity of the polymer crystal is 70% or more;
(III) The size of the polymer crystal is 300 nm or less. A polymer crystal containing a polymer crystal and a nucleating agent,
A polymer crystal characterized by satisfying the following conditions (I), (II) and (III ′):
(I) contains 0.1 to 0.5% by weight of nucleating agent;
(II) The crystallinity of the polymer crystal is 70% or more;
(III ′) The number density of the polymer crystals is 40 μm ⁻³ or more.   The polymer crystal body according to claim 1 or 2, comprising 0.15 to 0.4% by weight of a nucleating agent.   The polymer crystal according to any one of claims 1 to 3, wherein the crystallinity of the polymer crystal is 80% or more.   The polymer crystal according to any one of claims 1 to 3, wherein the crystallinity of the polymer crystal is 90% or more.   The polymer crystal body according to claim 1, 3, 4, or 5, wherein the size of the polymer crystal is 100 nm or less.   6. The polymer crystal according to claim 1, 3, 4, or 5, wherein the size of the polymer crystal is 20 nm or less. 6. The polymer crystal according to claim 2, wherein the polymer crystal has a number density of 10 ³ μm ⁻³ or more. 6. The polymer crystal according to claim 2, wherein the polymer crystal has a number density of 10 ⁵ μm ⁻³ or more.   The polymer crystal according to any one of claims 1 to 9, wherein the polymer is a general-purpose plastic.   The polymer crystal according to any one of claims 1 to 9, wherein the polymer is polypropylene. The polymer crystal is
A polymer melt containing 0.1 to 0.5% by weight of a nucleating agent having a number average particle size of 0.1 μm or less is stretched at a strain rate equal to or higher than the critical elongation strain rate, and the polymer melt is oriented and melted. 10. The method according to any one of claims 1 to 9, which is produced by a production method comprising an alignment melt crystallization step for bringing a liquid state and a rapid crystallization step for cooling crystallization while maintaining the orientation melt state of the polymer melt. 2. The polymer crystal according to item 1.   The polymer crystal according to claim 12, wherein the polymer melt is a general-purpose plastic melt.   The polymer crystal according to claim 12, wherein the polymer melt is a polypropylene melt.   The polymer crystal according to claim 12, wherein the polymer melt is an isotactic polypropylene melt.   The polymer crystal body according to any one of claims 1 to 15, which is a bulk molded body.   The polymer crystal body according to claim 16, which is an extruded body.   The polymer crystal body according to claim 16, which is an injection-molded body.   The polymer crystal body according to claim 16, which is a blow molded body. A polymer melt containing 0.1 to 0.5% by weight of a nucleating agent having a number average particle size of 0.1 μm or less is stretched at a strain rate equal to or higher than the critical elongation strain rate, and the polymer melt is oriented and melted. An alignment melt-forming step to make a liquid state;
And a rapid crystallization step of cooling and crystallization while maintaining the orientation melt state of the polymer melt.   The method for producing a polymer crystal according to claim 20, wherein the polymer melt is a general-purpose plastic melt.   The method for producing a polymer crystal according to claim 20, wherein the polymer melt is a polypropylene melt.   The method for producing a polymer crystal according to claim 20, wherein the polymer melt is an isotactic polypropylene melt.

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