CA1211592A - Mixed polyvinyl chloride and acrylic polymer fibers and threads, and their manufacture - Google Patents

Abstract

The present invention relates to filaments, threads or fibers consisting of at least 75% by weight of polyvinyl chloride and up to 25% by weight of acrylic polymer and their process for obtaining. Said yarns and fibers have, after retraction in boiling water, a tenacity of at least 20 cN / tex, preferably at least 25 cN / tex, an elongation of less than 60%, preferably of 50%, a rate of residual shrinkage in boiling water less than 5%, preferably less than 2%. They are obtained by wet spinning, double drawing, stabilization under tension and free retraction. The yarns and fibers according to the invention can in particular be used for the production of fabrics or knits, capable of being dyed with broth.

Description

The present invention relates to filaments son fibers and other synthetic articles made of synthetic material at least 75% by weight of ordinary polyvinyl chloride and up to 25% by weight of acrylic polymer.
Polyvinyl chloride fibers are popular in the textile sector due to certain particular properties proud such as flame retardancy, negative triboelectricity, resistance to light, chemical inertness and insulating power thermal, acoustic and electrical. . Ioutefoi6 polychloride of ordinary vinyl most commonly prepared used, that is to say hot, at temperatures between 0 and B0C, because the least expensive is a pre-tactical finance were yielding a transition temperature the second order T of the order of QUE As a result, the wires and fibers obtained from tactical polyvinyl chloride alone have after stretching and stabilization and before shrinking sufficient mechanical qualities for their textile transformation, but finished articles have too high a withdrawal rate seen, being able to go ~ usqu ~ 30 Z; if they are subjected to this stage a retraction treatment, ifs then have ~ ualltés insufficient mechanical to avoid re-stretching during textile conversion, which results in too much shrinkage important to be able to dye these fibers "to the broth"; this say according to a usual dyeing process THAT.
In order to improve the properties of base fibers polyvinyl chloride it has been developed new polo mothers from vinyl chloride by a technique based on a pol ~ merisatioll performed at lower temperatures OC
and descending to -QUE or even lower, in the presence of these:
suitable talysers, effective at these temperatures These new polymers, predominantly syndic-tactics have a second order transition temperature (T) generally higher than conferring on wires and fibers obtained better thermal Slow and properties significantly ~ m ~ lior ~ es compared to textile products from ordinary vinyl polychloride. French demand born 2 161 oB4 published 06.07.1973 illufitre of fibers with good properties mechanical basis of this type of polymer. However, such a squeeze-due to low temperature polymerization is a process e ~ tremement expensive which considerably increases the cost price of fibers and takes away a lot of interest from their industrial production.
oven improve the di ~ olutlon of polyvinyl chloride ~ ynd ~ otactlque, we tried to e l 8 D ger with 5 to 50% by weight of polyacrylonitrile, so as to obtain stable solutions high temperature. Month such a mixture does does not solve the problem of the cost price of polyvinyl chloride syndiotactic.
We have also proposed, Delon the French patent 1,359,178 improve polyvinyl chloride fibers and yarns (PIC) by mixing ordinary polyvinyl chloride with polo vinyl chloride on chlorinated. This 601utiou which allows effective-hold better yarns and fibers mechanical is a solution yelled all the more expensive in-industrially that the proportion of polyvinyl chloride on chlorinated added this important.
It has now been found that it was possible to obtain yarns and fibers containing a preponderant proportion of polo ordinary vinyl chloride with good characteristics antique antiques, especially both good toughness and a not too high elongation linked to a low residual shrinkage rate, - as well as good dimensional stability, stable from being dyed Delon the pr ~ c ~ d ~ dye seen broth, by adding the polo ordinary vinyl chloride with a small amount of polymer Jo acrylic, using a continuous industrial process, this is ~
dan economic collditlo ~ s int ~ ressant ~ 6.
More particularly, the present invention relates to filaments, threads, fibers, consisting of 75 92 y by weight of polo ordinary vinyl chloride and 8 25 by weight of acrid polymer fig, having after shrinking in boiling water, a teta-cited at least 20 between an elongation the lower rupture 60 X, a residual retr ~ lt rate in the lower boiling lobs 5 dr Preferably, the toughness is at least 25 CN / tex ~ Walloon germinate at break less than 50 y, and the withdrawal rate in saturated water vapor Los less than or equal to 10 2.
The present invention relates to ~ galemenL a method for obtaining basic yarns and fibers from 75 to 92% by weight of polyvinyl chloride and 25 X of an acrylic polymer, which consists in spinning a polymer concentration solution included between 15 and 30 Y preferably 20 25 2, in a coagulating bath containing S 90 Z by weight of d ~ methylformamide and 35 10 by weight of water, preferably 75 90 by weight of dimethylforma-Gide and 25 10 X by weight of maintained a coma temperature taken between 0 and THAT carry out a first drawing of the mounted in a medium of water and dimethylformamide, preferably between 20 and QUE at a rate between 2 and 4 X, wash said filaments, stretch the filaments again in a fluid medium aqueous at a temperature higher than THAT, a rate included between 3 and 5 Y the overall drawing rate being between 6 and 10 X; the filaments then do so and then submitted a stabilization under tension in a temperate aqueous medium erasure seen equal to THAT then to a retraction the state free in aqueous fluid medium At a temperature greater than or equal THAN.
By ordinary polyvinyl chloride, an essential is-Gent le ~ vinyl chloride having a transition temperature second order generally between 65 and QUE consisting of Faisal predominant by the atavic isomeric form Such a polymer is most commonly held in the least costly manner by known techniques Fe bulk polymerization, suspension or emulsion temperatures generally higher than PLUS
generally between 20 and QUE or even more.
By the expression polyvinyl chloride, we mean loudly copolymers containing at least 95% (by weight) of chloride vinyl as defined above copolymerized with co ~ lposés there having donkey double bond ~ hyl ~ ique, such as ac ~ tate vinyl vinyl esters and ethers and ~ me ~ h3acryliques, acryl-lonitrile, olefins such as ethylene By acrylic polymer is meant the polymer containing at least 85% by weight of acrylonitrile and ~ u8qu ~ 15 by weight of units from one or more ethylenic mono-mothers co-poly despicable with acrylonitrile such as vinyl compounds6 vinyl chloride and acetate for example, ester acids and methacrylic seen acrylic amides ~ methacrylonitrile, Ifs compounds and carboxylic acid function ~ elsque itaconic acid y or sulfonic acid function such as sulfonic vinyl compounds niques, allie- and methallyl-sulfon acids ~ that, derivatives aromatic sulfones, ~ tyrene-sulfonic acids; vinyloxyarene sulionics, basic type vinyl drive such as vinyl pyridine and its alcohol derivatives vinyl and dialkyl oxides y amine etc .. Toutefofsy preferably use copolymers ~ res acrylonitrile rather than homopclymer.
The filaments, threads, fibers according to the present invention, while retaining the interesting qualities of free polo vinyl chloride especially flammability ~ power insulation, even with low polymer usage acrylic, less than 25 Z, surprisingly, crackles very interesting mechanical tris tics: after shrinking in brilliant water they have a tenacity of at least 20 cN / tex, preferably seen minus 25 Latex an allorl ~ ing breakage sorter 60 y, preferably lower than Jo these two carat nlaya ~ l importance of relying on a withdrawal rate residual in boiling water below 5 X, preferably there sorter at 2 y.
In addition, the yarn and fibers have a dimensional stability water vapor to QUE such that their removal if duel is less than 7 'y.
The yarns and free according to the present invention are obtained as follows . the two polymers are first introduced cold in the desired proportions in dimethylfonmamide then the stirred solution is heated to a temperature of at least THAT, the total polymer concentration of the solution being included between 15 and 30 X, preferably between 20 and 25 y. The solution as well obtained is spun in a coagulating bath constitutes from 65 to 90 X in weight of dimethylformamide and 35 to 10 'b by weight of water, maintained low temperature generally between 0 and pre lake frowns between 5 and lay. The filaments are then drawn a pro-mother once in a medium consisting of dimethylfor ~ amide and water generally in proportion of 3 ~ -70 70-30 X by weight, per step-wise on suitable rollers or in a bin, a Lease of 2 4 X, preferably between 10 and QUE, the stretching rate being the higher the higher the temperature, then weary, usually in running water, room temperature in a horizontal bin. During washing there may be low rate controlled retraction by simply adjusting the feeds calves. The filaments are again drawn in a fluid medium aqueous temperature of yew, preferably in a bath boiling water, possibly in a tube, a rate included between 3 and 5 X, then teaches in the usual way.
They then undergo stress stabilization in mini aqueous fluid temperature greater than or equal to THAT;

it can be reread silk or its own a boiling water bath lanteJ either by stabilization in pressurized water vapor for 1 3 seconds temperature between 105 and QUE.
They are then retracted in a fluid medium which temperature between QUE and QUE.
Free retraction can be efieotu ~ e in boiling water for a variable duration, for example at least 10 minutes in go-Nepal from 10 to 20 minates, or in steam sutured by example by passing through a nozzle as described in the patent French born 83 329/1 2 ~ 9 491.
In such a nozzle, the filaments are treated by the saturated water vapor at a temperature between QUE and THAT and are simultaneously shrunk and curled which allows a better subsequent textile workability. Moulting, in the case where the retraction is carried out in boiling water, this is preferably preceded by mechanical crimping according to any process Known for the same purpose to improve subsequent workability.
All operations since dissolution can be performed continuously, donation under conditions easily industrially feasible and economically attractive.
Polymers in solutions spun according to the present application may contain usual fillers such as stabilizer, provided pigments, plasticizing dyes capable of improving iron some of their properties such as color or affinity dye electrical resistivity, and such a process makes it possible to obtain an attractive price for filaments capable of undergoing all textile operations a-required for their finishing and dletre used for the reacti-station of fabrics, knitwear, non-woven articles, etc. alone or in line with other threads, which can undergo ha-washing and cleaning rituals under appropriate conditions private Hans {waxed later.

y, The following examples in which parts 6 1 enter tooth by weight are given as an indication / may not limit the invention.
In the following examples, the values of Lnacity and ~ slow extension hides by means of a device known in the art . *
- trade HOU the name of IMST ~ DN, by measurement of the maximum force hou supports a sample, reported Lon titre, ce force removing it measured at gradients of constant elongation.
Example 1 -- Introduced into dLmethylformamide Maintained THAT
first about 4 parts by weight of a copolymer made up of 91.4 by weight of acrylonitrile, 7.75 X of methyl methacrylate and 0.85 of ~ sodium ethallylsulfonate and then 16 parts of polyvinyl chloride tactical so as to obtain a solution Lethal polymer concentration of 20 X by weight; this 60-elf is then heated QUE then spun through a proud with 2,750 orifjc ~ s Hans a coa ~ ulsnt bath maintained THAT and containing 85% by weight of dimethylformamide and seen therein with water.
The filaments pass through a second container maintained ONLY containing 35 'by weight of dimethylformamide per 65 X of water where lob undergo a stretch of 3 X. After washing the water against the current, they undergo Gent then another stretch of 3 X in a tank of boiling water then are taught They are then fixed under tension in the presence of steam of water HOU pressure for two seconds a temperature of THAT before being r ~ trsctés in a vain of boiling water during 20 minutes. The characteristics of the filaments obtained are combined in the table below.
B - A tactical polyvinyl chloride solution is prepared pure and with a concentration of 20% by weight, it is spun in the industrial way than laughed above. The filaments obtained are then processed from the mul-nth indicated in A.
* (trademark) Carsct lys ~ ris ~ iques filaments obtained are gathered in the table below.
Temple 1 A Example 1 B
toughness ~ .cN / tex 28 18 elongation 5 60 residual shrinkage (boiling water) ~ 5 ~ 5 title to strand dLex 2.0 2.0 residual vapor withdrawal water other than QUE X 24 Example 2_ Is introduced into d ~ methylfor ~ amide maintained SUC envi-non dart 2 parts by weight alum copolymer consisting of 91.4 Z
by weight of acrylonitrile, 7.75 of methyl methacrylate eu 0.85% sodium methallylsulfonate, and then 18 parts of tactical polyvinyl chloride: a solution of total polymer concentration of 20 wt. This solution is then heated QUE and then spun through a coma die carry 2,750 orifices coagulating bath maintained at QUE and containing 85 Z by weight of dimethylformamide and 15 Z of water.
ZOU The filaments pass through a second maintained tank THAT contains 35 X by weight of dimthylformamide and 65 of water are born where they undergo feels a stretch of 2.5 X. They are then washed with water current room temperature then shot again in a bath boiling water a rate of 3.52 y, and teaches They do set energized in a boiling water bath before being retracted salted in a bath of boiling water for 20 minutes.
The filaments thus obtained have the characteristics sweating:
tenacity cNttex 21 elongation X 55 residual shrinkage Z (boiling water) 5 stranded title dtex 1.63 residual shrinkage in steam of water seal THAT X 10

Claims (12)

The achievements of the invention, about which them an exclusive property right or lien is claimed, are defined as follows: 1. Polychloride filaments, threads or fibers vinyl and acrylic polymer, characterized by the fact that they are made up of - 75 to 92% by weight of polyvinyl chloride - 8 to 25% by weight of acrylic polymer and that they have after shrinking in boiling water - a residual shrinkage in boiling water of less than 5%
- a tenacity of at least 20 cN / teX, - an elongation at break of less than 60%. 2. Filaments, threads or fibers according to the claim tion 1, characterized by the fact that they have a rate residual shrinkage less than 2%, measured in water boiling. 3. Filaments, threads or fibers according to the claim tion 1, characterized by the fact that they have a toughness of at least 25 cN / tex. 4. Filaments, threads or fibers according to the claim tion 1, characterized by the fact that they have an extension breaking strength less than 50%. 5. Filaments, threads or fibers according to the claim tion 1, characterized by the fact that they have a shrinkage in saturated steam at 105 ° C less than 10%. 6. Process for obtaining filaments, threads or fibers as defined in claim 1, charac-terrified by the fact that we are spinning a concentra-tion in polymer between 15 and 30% in a bath coagulant consisting of 65 to 90% by weight of dimethylformamide and 10 to 35% water, maintained at a temperature between 0 and 15 ° C, then the filaments are removed first times in a medium consisting of water and dimethylformamide, at a rate between 2 and 4 X, washed and then stretched new in an aqueous fluid medium at a temperature higher than 90 ° C, at a rate between 3 and 5 X, the rate overall drawing being between 6 and 10 x, sized, subjected to tension stabilization in a fluid medium aqueous at a temperature greater than or equal to 100 ° C, then to a retraction in the free state in an aqueous medium at a temperature of at least about 100 ° C. 7. Method according to claim 6, characterized by the fact that the first stretching is carried out in a medium consisting of 30 to 70% by weight of dimethylformamide and 70 to 30% water. 8. Method according to claim 6, characterized by the fact that the first stretching is carried out at a temperature between 10 and 50 ° C. 9. Method according to claim 6, characterized by the fact that the second stretching is carried out in a bath of boiling water. 10. The method of claim 6, wherein stress stabilization treatment is performed in a boiling water bath. 11. The method of claim 6, wherein stabilization is carried out in the presence of water vapor under pressure for 1 to 3 seconds at a temperature between 105 and 130 ° C. 12. Method according to claim 6, characterized by the fact that the free retraction processing is performed in boiling water for at least 10 minutes.