DE1228753B - Manufacture of threads from mixtures containing polypropylene - Google Patents

Description

FEDERAL REPUBLIC OF GERMANY

GERMAN

PATENT OFFICE

EDITORIAL

Int. Cl .:

DOIf

German class: 29 b-3/65

Number: 1 228 753

File number: E20061IVc / 29b

Filing date: October 19, 1960

Opening day: November 17, 1966

It is known that polypropylene, in particular partially or completely crystalline polypropylene, spun into synthetic fibers with exceptional physical properties can. The polymers available, however, have a number of disadvantages that prevent their use severely restrict the manufacture of general purpose threads. For example, high molecular weight, thread-forming crystalline polypropylenes, relatively insoluble, chemically inert, hydrophobic Fabrics. Since water cannot easily penetrate polypropylene, it can also be used according to the usual Staining process cannot be stained in a satisfactory manner. Because it is chemically relatively inert it cannot be permanently colored even with dyes soluble in hydrocarbons. In addition, threads and fibers made of essentially crystalline polypropylene can also be used many disperse dyes and dyes containing metal atoms are not readily colored will. In particular, no deep shades with good light and gas fastness properties can be found achieve. In addition, the usefulness of polypropylene threads is due to their susceptibility to oxidative degradation, instability to ultraviolet light and poor weather resistance limited.

The object of the invention is to provide polypropylene threads with improved dye affinity, the colored with a variety of disperse dyes and dyes containing metal atoms that normally do not dye unmodified polypropylene.

The subject of the invention is a method for producing threads by melt spinning Mixtures containing polypropylene, characterized in that a mixture is spun that Polypropylene and 1 to 25 weight percent of a polyvinyl acetal having a molecular weight of at least 1000, which consists of at least 50 mol percent of acetal groups.

Mixtures which contain 5 to 15 percent by weight of the polyvinyl acetal are preferably spun.

The polypropylene threads produced according to the invention have a greatly improved resistance against oxidation and weather influences as well as ultraviolet light in addition to good ones general physical properties.

The dyed threads have excellent light and gas fastness and unexpectedly good resistance to oxidation on.

Although unmodified polypropylene is useful in making threads from mixtures that
Contains polypropylene

Applicant:

Estman Kodak Company,

Rochester, N. Y. (V. St. A.)

Representative:

Dr.-Ing. W. Wolff and H. Bartels, patent attorneys, Stuttgart 1, Langestr. 51

Named as inventor:
Harry Wesley Coover Jr.,
Frederick Blount Joyner,
Kingsport, Tenn. (V. St. A.)

Claimed priority:

V. St. v. America February 4, 1960 (6596)

shows no affinity for dyes, but with certain dyes it can be used to produce pale shades dye very poor fastness properties. Surprisingly, it has now been shown that the shades, which are achieved by using a certain dye on threads made of unmodified polypropylene from those shades that are completely different that you can use with the same dyes Achieved threads produced according to the invention. This unexpected result shows that those from the described Polymer blends of spun threads have properties that are common to threads made from simple threads Mixtures of the polymers in question were normally not to be expected.

The threads produced according to the invention can be mixed with any stabilizers customary for polyolefins be stabilized against thermal degradation and against the effects of the weather. As functional it has have been found to add such stabilizers to the polymerization mixtures prior to spinning.

The threads that can be produced according to the invention can be used to achieve high tenacity, low elongation values and other excellent properties are drawn, values being obtained which correspond to threads made of unmodified polypropylene. This result is surprising because the polyvinyl acetals are essentially non-crystalline, if they are made by conventional methods, and therefore threads with low tenacity, high shrinkage deliver with no commercial value. With that in mind

609 727/407

it was to be expected that these polymers, when used to modify polypropylene threads, would whose properties would adversely affect.

The polyvinyl acetals used to carry out the method of the invention are known materials. They can be prepared by known methods by hydrolysis of polyvinyl acetate and the following Produce reaction with an aldehyde. According to page 358 of Schildknecht's book, "Vinyl and Related Polymers", New York, 1952, the term "polyvinyl acetal" is used for Polyvinyl alcohols, the majority of which are hydroxyl groups condensed with aldehyde. 1 mole of aldehyde condenses with two hydroxyl groups to form acetals. The remaining hydroxyl groups can be substituted freely or by acyl groups.

It has proven advantageous to use polyvinyl acetals which are at least 70 mol percent There are vinyl acetal groups which differ from the aldehydes mentioned below or mixtures thereof derive, it being possible for the remaining hydroxyl groups of the polyvinyl alcohol to be free or acylated. Typical examples are: poly (acetaldehyde vinyl acetal), poly (n-valeraldehyde vinyl acetal), poly (formaldehyde vinyl acetal), Poly (butyraldehyde vinyl acetal) and poly (heptaldehyde vinyl acetal). To produce the polyvinyl acetals used according to the invention can for example formaldehyde, acetaldehyde, propionaldehyde, butyraldehyde, valeraldehyde, hexaldehyde, Benzaldehyde, crotonaldehyde, heptaldehyde, pelargonaldehyde, dodecanaldehyde, margarinaldehyde, octadecanaldehyde and the like, as well as mixtures thereof, can be used. In general, preference is given to polyvinyl acetals, which differ from low, saturated ones derive aliphatic aldehydes. Polyvinyl acetals of saturated aliphatic ones have proven particularly useful Aldehydes with up to 8 carbon atoms, which in turn are those of formaldehyde, Acetaldehydes and butyraldehyde and mixtures thereof have proven particularly advantageous.

According to the method of the invention, the polypropylene mixtures in Tempeiaturen of 25 to 65 ⁰ C below that temperatures be spun, which are necessary for the melt spinning of pure polypropylene.

The mixtures that are spun by the process of the invention can be used in any manner be produced, be it by mechanical mixing, coprecipitation or another mixing process, for example by means of rolling at elevated temperatures or by multiple extrusion processes.

Preferably, polypropylenes with a normal density of about 0.900 and an intrinsic viscosity, measured in tetralin at 145 ⁰ C, of 0.9 to 1.2 used as the starting material. The specified basic viscosity is identical to the so-called inherent viscosity i? _iBÄ> which is defined as the ratio of

In"

where η _τ = ~ = ^ -, ie the relative viscosity and c is the concentration of the polymer in grams per 100 ml of solvent. (See: FW Billmeyer, Jr., Textbook of Polymer Science, Interscience Publishers, New York, 1965,

Pp. 80 to 81.)

The term »normal density« refers to a density that is determined on a sample, which has been annealed to achieve maximum crystallinity. A common annealing process exists

¹⁵ seconds is to place the sample in a tube and heat it under high vacuum or in a nitrogen atmosphere to just below the softening point and then let the sample cool down slowly. Polypropylenes with intrinsic viscosities above 1.2 can also be used to practice the process of the invention, but it is then usually necessary to thermally degrade these blends to a low viscosity in order to achieve optimum melt spinning and filament properties.

Required for such degradation Tempsraturen are usually above 300 ⁰ C and often lead to a significant loss of modifier by depolymerization. Polypropylenes with basic viscosities below 0.9 can also be used, but do not lead to threads with optimal physical properties.

The polypropylene blends can be made into threads with different cross-sections which, for. B. also clover-shaped or Y-shaped can be spun.

example 1

Several mixtures of crystalline polypropylene (basic viscosity = 1.0; density = 0.912) and polyacetaldehyde vinyl acetal) prepared by Pastilles of the two polymer products mixed mechanically, then pressed out of the melt and were again brought into lozenge form. The poly (acetaldehyde-vinyl acetal) was replaced by the Acetyl groups of polyvinyl acetate have been made up to 70% by acetaldehyde. The received Mixtures were then made into 34 monofilaments with those listed in the table below Properties melt-spun. Knitted tubes from the threads can be mixed with disperse dyes, such as 4 - (4 '- hydroxyethylanilino - 5 - nitro -1,8 - dihydroxyanthraquinone, 2-nitro-4-sulfonamido-4'-ethoxy-diphenylamine and amyl-4- (l'-amino-2'-methoxy-anthraquinonyl) -carbamate, by boiling for one hour in aqueous dye bands in deep shades stain. Even lower tones were obtained when using carriers such as benzyl n-butyrate. All Samples showed excellent fastness to ultraviolet light when treated in for 20 hours a fadeometer.

Characteristic value

Percentage ratio of polypropylene to poly (vinyl acetal)
100: 0 I 95: 5 I 90:10 I 85:15 I 80:20

Basic viscosity

Total titer den

Strength, g / den

Strain, %

Young's modulus, g / den.

0.93 1.00 0.90 1.06 0.82 223 180 184 228 216 7.35 7.42 6.86 6.60 5.07 18th 13th 13th 23 25th 63 97 87 56 76

Similar results were obtained when using a polyvinyl acetal containing 50% vinyl acetal groups, derived from n-valeraldehyde, 35% vinyl acetate groups and contained 15% vinyl alcohol groups.

Example 2

A mixture of 9 parts of crystalline polypropylene (intrinsic viscosity = 1.05; density = 0.914) and 1 part of poly (vinyl formal) with 79 mol percent vinyl formal groups and 21 mol percent vinyl alcohol groups was prepared by mechanically mixing grains of the two polymers. The mixture was then extruded from the melt into a rod about 3.2 mm in diameter and cut into chips about 3.2 mm in length. The chips were then melt spun into a yarn of 34 filaments at a spinning temperature of 260 ⁰ C. The unmodified polypropylene required a melt spinning temperature of 280 ° C to achieve optimal spinning properties. A knitted piece, which was used for dyeing tests, was produced from the thread obtained. The knitted fabric had excellent dye affinity for disperse dyes. When using 4- (4 '- /? - hydroxyethylanilino) - 5 - nitro -1,8 - dihydroxy - anthraquinone and amyl - 4 - (1' - amino - 2 '- methoxy - anthraquinonyl) - carbamate, deep colors were achieved .

Other poly (vinyl formals) that can be used with equally good results are for example those with 5 to 20% vinyl alcohol or vinyl acetate groups or a combination such groups.

Example 3

Blends of crystalline polypropylene with poly (vinyl butyral) were melt molded mechanical blends of the two polymers. As polyvinyl butyral) was a polymer with 80% vinyl butyral groups, 19% vinyl alcohol groups and 1% vinyl acetate groups used. The resulting mixtures were spun into threads of 34 single threads, which are as follows Features:

Characteristic value

Basic viscosity

Overall, the

Strength, g / den

Strain, %

Young's modulus, g / den

Percentage ratio of polypropylene

to polyvinyl butyral)
96.5: 3.5 | 88:12 | 75:25

1.07
154,

8.22
17th
89

0.92
160
7.08
20th

81

0.88
199

5.71
19th
58 active pipes, the threads were easily with 4 - (4 "-beta - Hydr oxyäthylanilino) - 5 - nitro -1,8 dihydroxyanthraquinone, amyl-4- (l'-amino-2'-methoxy-anthraquinonyl) carbamate and stain 2-nitro-4-sulfonamido-4'-ethoxy-diphenylamine. Deep shades with good light and gas fastness properties were achieved.

Instead of poly- (vinylbutyral), with corresponding results, poly- (isobutyraldehyde-vinyl acetal) be used.

Example 4

The procedure described in Example 2 was repeated, but this time a poly (heptaldehyde-vinyl acetal) with about 35% vinyl alcohol groups and about 5% vinyl acetate groups used in place of the poly (vinyl formal). The received Thread showed a maximum strength of 6.8 g / den and could easily be put in with disperse dyes dye deep shades with good lightfastness properties.

Corresponding results were obtained when instead of poly (heptaldehyde-vinyl acetals) polyvinyl acetals, derived from pelargon aldehyde, margarine aldehyde and oleic aldehyde.

Example 5

The procedure described in Example 3 was repeated, but this time a poly (propionaldehyde vinyl acetal) used in place of poly (vinyl butyral). The poly (propionaldehyde vinyl acetal) used contained 90% vinyl propional groups and about 10% vinyl alcohol groups. It became threads obtained with strengths of 4.9 to 7.5 g / den. The threads could be deeply dispersed with disperse dyes Coloring shades of color.

The polypropylene threads produced according to the invention can be used in the same way as conventional polypropylene threads be used. For example, they can be used for wool-like blankets, for the production of Covers can be used for car seats or for ship ropes.

Claims (1)

Claim: Process for making filaments by melt spinning mixtures containing polypropylene contain, characterized in that a mixture is spun, the polypropylene and 1 to 25 percent by weight of a polyvinyl acetal having a molecular weight of at least 1000, which consists of at least 50 mol percent of acetal groups.