DE901332C - Process for the production of artificial, non-matt structures from linear polymers, preferably polyhexamethylene adipic amide - Google Patents

Description

(WiGBl. P. 175)

ISSUED JANUARY 11, 1954

P 3599IV c 129b

acid amide

The invention relates to the production of threads with several individual threads or fibers with fine Synthetic linear polymer titers. It is characterized by the fact that the threads have a finely divided, contain indifferent material that causes the threads or individual threads to tear during of cold stretching is significantly reduced.

Melt spinning and cold drawing of synthetic linear polymers are known, e.g. B. off U.S. Patents 2071250, 2 071 251, 2,071,253 and 2,130,948 in which melt spinning and stretching of polyamides, polyesters, polyethers, polyanhydrides and the polymer blends or copolymers, e.g. B. polyamide-polyester is described. The most interesting and Most valuable of these polymers are the synthetic linear polyamides that have been used in recent years both of the above-mentioned patents are described in more detail. It is also known that other synthetic linear polymers, e.g. B. polyvinyl chloride, polyacrylonitrile and mixed polymers of vinyl acetate and vinyl chloride processed using the melt spinning and cold drawing process can be.

The invention can be explained in its further meaning tion on the melt spinning and cold drawing of any fiber-forming synthetic linear polymer use.

According to the invention are artificial, non-matted structures, such as threads or fibers made from linear polymers by the dope before or after the polymerization with inert materials of small particle size, such as titanium dioxide, preferably in amounts of about 0.005 to ° '° 5 ⁰ ^ ⁰ offset, spun, stretched and finished. According to a particular embodiment of the invention, a synthetic linear polyamide, preferably polyhexamethylene adipamide, is used as the spinning mass.

One already has pigments or pigment-like substances made of synthetic thread-forming masses added to linear polymers, but around

Create 5 opaque or matt threads. However, it has not been recognized that a low content of less than 0.05% is more finely divided, more indifferent Substances in a melt made of synthetic linear polymers after melt spinning The result is threads that tear considerably less easily than spinning masses without this addition. Such a small one The amount that is to be added according to the present invention is also far from sufficient to achieve the technical effects of the

“5 knew procedures.

It is known that titanium dioxide can easily reduce the mechanical strength of the threads entry. It is also known that cold stretching is right because of the tensile force that has to be expended difficult. From this it could be concluded that the cold stretching of threads with the addition of a finely divided, indifferent material would cause the individual threads and threads to tear more easily. It was therefore very surprising that, with the small additions according to the invention the opposite occurs and threads of the finest titer can be produced.

example 1

Polyhexamethylene adipamide with a relative Viscosity of 33.5 with a homogeneously distributed addition of 0.01 <Vo titanium dioxide, on the Total weight calculated, were spun from the melt into a thread with 69 individual threads, which was then drawn to a yarn of 210 deniers at a draw ratio of 4.40 became. The thread had a tensile strength of 6.3 g / denier and an elongation of 16%. While of stretching, 0.2 complete threads occurred for every 0.453 kg of threads The thread was broken, and a test after the spinning mirror test showed four broken filaments on 1043 m of thread. The thread showed no noticeable matting. For comparison was the same polyhexamethylene adipamide with a relative viscosity of 33.5, but without addition of titanium dioxide, spun as a melt into a thread with 69 individual threads. The string was then stretched at the same 4.40 stretch. It became a thread with 69 single threads of 2ίο deniers with a tensile strength of 6.5 g / denier and an elongation of 14% obtain. During the stretching, 2.0 complete breaks occurred for every 0.453 kg of threads, and one test in the spinning mirror there were 40 broken individual threads per 1043 m thread.

Example

Polyhexamethylene adipamide with a relative viscosity of 34 and an addition of 0.05% titanium dioxide was spun from a molten mass into a thread with 69 individual threads and then spun to a thread of 210 deniers at a stretch ratio of 4.40. Of the The thread had a tensile strength of 6.2 g / denier and an elongation of 15%. While stretching 0.2 complete breaks occurred per 0.453 kg of thread on, and an examination in the spinning mirror showed two broken individual threads for 1043 m of thread each. Of the The shine of the thread was practically not affected.

A similar polyhexamethylene adipamide with a relative viscosity of 34 was used as a control without titanium dioxide as a molten mass spun into a thread with 69 individual threads and then stretched with a draw ratio of 4.40. The thread had a titer of 210 deniers, a tensile strength of 6.5 g / denier and an elongation of 14%. Several kicked while stretching complete breaks, and the test in the spinning mirror showed 70 broken individual threads each 1043 m of the thread.

A second sample of the same polymer melt spun into an ogfädigen thread spun. The thread was then drawn to a degree of stretch of 4.28. It was one thread with 69 monofilaments of 210 deniers with a tensile strength of 5.5 g / denier; and one Elongation of 19% obtained. Several complete breaks of the single filaments occurred during the stretch on, and a test · dm Spinnspäegel showed 88 broken individual threads on 1043 m thread each.

The two exemplary embodiments show that, according to the present invention, two very important ones Advantages. Firstly, the addition of a small amount of titanium dioxide in the woven makes it possible Polymers enable the drawing of shiny threads without too many breaks during the drawing Single threads occur. Second, the addition of the small amount of titanium dioxide has the consequence that a Thread of greater elongation is obtained. When stretching threads of the same type with a low- no Ren degree of stretching (see Example 2), the elongation is greater and the tensile strength is lower. But that Tearing in stretching and twisting was not decreased. Hence the effect of titanium dioxide not due to a change in the degree of stretching. On the other hand goes out of the Examples show that threads with a low addition of titanium dioxide at a higher degree of stretching can be pulled, but have the same elongation, which increases the performance the spinning machine means.

Although relative viscosities of 33.5 to 34.0 are mentioned in the examples, the relative viscosity between 15 and 60.

The term relative viscosity denotes the ratio of the absolute viscosity in centipoise

a solution of synthetic linear polyamide in 9o ° / cent formic acid (io ° / o of water and 90% formic acid) at a temperature of 25 ⁰ to the absolute viscosity in Zentipoisen of 90 ° / cent formic acid at a temperature of 25 ^0th A 8.4% solution of the synthetic linear polyamides, calculated on the total weight, which are completely soluble in 90% formic acid, is used for this determination. The moisture content of the polyamides is not taken into account when preparing the solutions for the polyamide-formic acid sample, if it is less than 0.4%. The absolute viscosity of 8.4 ° / o polyamide solution and the solvent alone is determined in the usual manner at 25 ^0, and the relative viscosity from the ratio of the two calculated to each other.

The invention is not limited to these examples and can be applied to melt spinning in general and stretching all of the filamentary synthetic linear polymers, e.g. B. the linear polyamides, can be applied. In addition, the invention also includes the drawing of polyamide threads, which in other ways, e.g. B. from a solution. The invention is limited essentially on fine denier filaments; d. H. less than 20 deniers per thread because of this Thread structures are stretched in the air, while much larger threads are in a spinning liquid are stretched and are therefore not particularly prone to breakage.

The invention is not limited to the use of titanium dioxide, but can also be used under Use of other finely divided, indifferent substances can be carried out, e.g. B. with powdered glass, Silica, Calcium Sulphate, Banum Sulphate, Kaolin, Clay, Zinc Oxide, Lithopone and other similar ones Substances that can be finely divided in the molten polymer.

The preferred addition is in amounts of o, o> n to 0.03% of titanium dioxide, based on the weight of the Polyamide related. The technical effect described is achieved with additions between 0.005 and 0.05% and obtain threads of high gloss. The optimal addition of every other finely divided, indifferent one Substance can be easily identified.

With the expression finely divided, indifferent substance is meant a substance which the polymer chemically does not attack and is distributed like the fabrics used for matting and coloring.

The present invention represents a significant advance in the manufacture of elongated shiny threads made of synthetic linear polymers and enables high performance and the production of excellent threads with the existing work facilities. It has shown, that the number of breaks of the threads during stretching is significantly reduced, so that a higher proportion of the product can be classified as completely flawless threads. It also has has been shown to be a highly drawn, glossy thread of high tensile strength and fine denier can be produced.

It was astonishing and unexpected that the filaments made in accordance with the present invention When tested in the spinning mirror, they do not show up nearly as wildly as the usual shiny threads. This makes a much better processability in the knitting and weaving machines and a better texture of the fabric is achieved.

It is also interesting that, contrary to previous experience, the refractive index of the added Pigments or finely divided, indifferent substance need not be taken into account. from The only thing that matters is that the amount of pigment added is such that it is achieved shiny threads are not affected.

Claims (1)

PATENT CLAIM: Process for the production of artificial, non-matted structures, such as threads or fibers, of linear polymers, preferably polyhexamethylene adipamide, characterized in that that the spinning mass before or after the polymerization with inert substances of small particle size, such as titanium dioxide, preferably in amounts of about 0.005 to 0.05% offset, spun, stretched and finished. 5677 12.