HK1068930A - Process for the production of polyurethane urea fibers by including a combination of polydimethylsiloxane, alkoxylated polydimethylsiloxane and a fatty acid salt in the spinning solution - Google Patents

Description

Method for producing polyurethane urea fibers by dry spinning or wet spinning

Technical Field

The invention relates to a method for wet spinning or dry spinning, in particular to a dry spinning method, which is used for producing polyurethane urea fiber, and the method is characterized in that the following components are added into a polyurethane urea component before spinning: 0.1-5 wt% polydimethylsiloxane having a viscosity of 2-20cSt (25 ℃); 0.1 to 5% by weight of an alkoxylated polydimethylsiloxane having a number-average molecular weight of less than 30,000g/mol and a viscosity of from 10 to 5000cSt (25 ℃); and 0.01 to 3 wt% of a fatty acid salt (wt% is based on the weight percentage of the polyurethaneurea fiber).

Background

Elastic polyurethaneurea fibers mean fibers composed of at least 85% by weight of a blocked polyurethane based, for example, on polyethers, polyesters and/or polycarbonates and aromatic diisocyanates and/or aliphatic diisocyanates. Polyurethaneurea fibers are generally prepared from spinning solutions according to a melt spinning process, a wet spinning process, or, in particular, a dry spinning process. Solvents suitable for the wet and dry spinning process are polar solvents, such as dimethyl sulfoxide, dimethylformamide, N-methylpyrrolidone, and preferably dimethylacetamide. The above spinning methods are described, for example, in Polyurethane-Elastomerfasem, H.Gall and M.Kausch in Kunststoff-Handbuch7, Polyurethane, editor: oertel, Carl Hanser Verlag Munich Vienna, 1993, page 679-694.

Polyurethaneurea fibers exhibit outstanding elasticity and significant extensibility, while having high recovery forces. Because of the good combination of the above properties, polyurethaneurea fibers are widely used in the clothing industry. The most important applications of the fibres are to give elasticity to linen, corsets and sportswear (e.g. bathrobes, swim pants) and in hosiery cuffs, socks, elastics or diapers.

The economic efficiency of producing polyurethaneurea fibers depends mainly on the spinning process used. In the dry spinning process, for example, a highly viscous spinning solution is fed to a heated spinning shaft, filtered, extruded through a porous nozzle, and the solvent is rapidly evaporated as a result of the hot spinning air used. The obtained single yarns are bundled together at the spinning shaft according to the required fineness to form yarn, and then the yarn is bonded together through a twisting device to form the substantial single thick yarn. An oil agent may be used. The finished wire is finally wound onto a bobbin. In the above method, one 480 dtex elastic yarn, for example, can be made of 36 filaments.

The economic efficiency of the polyurethaneurea fiber production process depends mainly on the winding speed of the yarn onto the bobbin. If the winding speed is high, the throughput of the spinning solution per spinneret is high. Therefore, the spinning solution or the additives contained therein should be selected such that the filter is not clogged during spinning. The spinning process must be interrupted if a blockage is still to occur. In this case, in connection with this, the yield and economic efficiency are reduced. Another equally important parameter in relation to economic efficiency is the data obtained for a textile yarn without the whole spinning process being changed. If the yarn data changes during spinning, it is possible to obtain a polyurethaneurea fiber that is out of specification. After removing products that do not meet the specifications, the economic benefits are reduced.

The object of the present invention is to produce a polyurethaneurea fiber in a manner that the data of the spun yarn is not changed during the whole spinning process and the productivity is improved.

Disclosure of Invention

It was found that, surprisingly, the above object can be achieved by the following process. A mixture of the following ingredients was added to the polyurethaneurea component prior to spinning: 0.1-5 wt% Polydimethylsiloxane (PDMS) having a viscosity of 2-20cSt (25 ℃); 0.1 to 5% by weight of an alkoxylated polydimethylsiloxane having a molar mass (number average molecular weight) of less than 30,000g/mol and a viscosity of from 10 to 5000cSt (25 ℃); and 0.01 to 3 wt% of a fatty acid salt (wt% is based on the weight percentage of the polyurethaneurea fiber); then the spinning process is carried out.

Methods for including pure polydimethylsiloxane in the spinning solution of polyurethaneurea fibers are basically disclosed. For example, DE-A-3912510 discloses a process for producing elastic fibers by a specific spinning process in which superheated steam is introduced to produce elastic fibers of coarse denier. The patent mentions the use of silicone oils as flow promoters among other possible additives. Us patent 4973647 also mentions that the spinning solution contains silicone oil. Neither document mentions that a spinning solution may contain a specific combination of oils with specific properties.

The inclusion of the pentylsiloxane-modified polydimethylsiloxane oil in the spinning solution is not the point of the invention, and the process has also been disclosed in the specification of DE-AS 1469452.

EP 643159 describes a process for producing polyurethaneurea fibers in a spinning solution comprising a combination of a polydimethylsiloxane having a viscosity of from 50 to 300cSt (25 ℃) and an ethoxylated polydimethylsiloxane having a viscosity of from 20 to 150cSt (25℃). However, the use of a spinning solution containing the mixture recommended in the above patent application reduces the effect of the antiblocking agent (such as magnesium stearate). In order to obtain the necessary adhesion for processing the polyurethaneurea fibers into, for example, a woven fabric, it is necessary to include an additional amount, i.e., an increased amount, of the antiblocking agent in the spinning solution. Increasing the amount of detackifier (e.g., magnesium stearate) results in a shorter filter life in the spinning process due to increased clogging. The spinning process is interrupted due to the necessity of replacing the filter prematurely, thereby reducing the yield. Furthermore, the mixtures proposed in the above patent applications, depending on time and temperature, lead to the agglomeration of magnesium stearate before it is added to the polyurethaneurea component which is fed to the spinning process. The agglomeration that forms over time can alter the effectiveness of magnesium stearate as an anti-tacking agent. As the spinning process continues, textile data, such as adhesion, may change over time. The off-specification polyurethaneurea fiber is then removed by complicated operations, resulting in a decrease in yield. The above publication does not mention that the viscosity of the polydimethylsiloxane used must be below 50cSt (25 ℃ C.). According to the invention, the spinning solution contains a mixture of the following components: polydimethylsiloxanes (PDMS) having viscosities of from 2 to 20cSt (25 ℃), alkoxylated polydimethylsiloxanes having viscosities of from 10 to 5000cSt (25 ℃), and fatty acid salts do not give the above-mentioned disadvantages with regard to the economic efficiency of the production of polyurethane urea fibres.

Methods of applying a mixture of polydimethylsiloxane and polyether modified PDMS to the finished spun elastic yarn by dipping, spraying or with a roller have also been disclosed (see JP 57128276 or JP 03146774). The oil agent can improve the unwinding performance of the elastic fiber in the warping and knitting processes. This is not mentioned in those specifications in which the spinning solution contains the mixture. Likewise, it is not mentioned that the mixture contained in the elastane spinning solution, in particular the mixture according to the invention containing the above-mentioned components, can increase the productivity of the spinning process.

Detailed Description

The invention provides a polyurethane urea fiber, which is characterized by comprising the following components:

A) a polyurethaneurea polymer in an amount of 99.7 to 65% by weight, preferably 99.5 to 80% by weight, more preferably 99 to 85% by weight,

B) polydimethylsiloxane in an amount of from 0.1 to 5% by weight, preferably from 0.2 to 3% by weight, more preferably from 0.3 to 2% by weight, having a viscosity of from 2 to 20cSt (25 ℃),

C) alkoxylated Polydimethylsiloxane (PDMS) corresponding to general formula (1), in an amount of from 0.1 to 5% by weight, preferably from 0.2 to 3% by weight, more preferably from 0.3 to 2% by weight,

wherein

PE is a monovalent radical-CH₂-CH₂-CH₂-O(ep_v/po_w)_mZ，

eo represents an ethylene oxide, and the reaction product of ethylene oxide,

po represents propylene oxide, and

z is hydrogen or C₁-C₆The alkyl group of (a) is,

v and w are integers of 0 or more and are not 0 at the same time,

x, y and m are integers greater than or equal to 1, preferably such that the number average molecular weight of formula (1) does not exceed 30,000g/mol and C) has a viscosity of from 10 to 5000cSt (25 ℃),

D) saturated or unsaturated, mono-or difunctional C₆-C₃₀In an amount of 0.01 to 3% by weight, preferably 0.05 to 2% by weight, more preferably 0.1 to 1.5% by weight, of a metal salt of a fatty acid, wherein the metal is selected from the metals of main groups 1, 2 or 3 of the periodic table or zinc, and

E) additives in an amount of 0 to 20% by weight, preferably 0 to 15% by weight.

The present invention also provides a process for producing an improved polyurethaneurea fiber by dry or wet spinning, preferably dry spinning, the process comprising: preparing a spinning solution, spinning the spinning solution using a spinneret and forming a yarn under the spinneret by drying or removing the solvent in a coagulation bath, and then finishing and winding the yarn, characterized in that the following components are added to the polyurethaneurea solution before the spinning solution is spun into polyurethaneurea fibers:

B) polydimethylsiloxane in an amount of from 0.1 to 5% by weight, preferably from 0.2 to 3% by weight, more preferably from 0.3 to 2% by weight, having a viscosity of from 2 to 20cSt (25 ℃),

C) alkoxylated Polydimethylsiloxane (PDMS) corresponding to general formula (1), in an amount of from 0.1 to 5% by weight, preferably from 0.2 to 3% by weight, more preferably from 0.3 to 2% by weight,

wherein

PE is a monovalent radical-CH₂-CH₂-CH₂-O(eo_v/poO_w)_mZ，

eo represents an ethylene oxide, and the reaction product of ethylene oxide,

po represents propylene oxide, and

z is hydrogen or C₁-C₆The alkyl group of (a) is,

v and w are integers of 0 or more and are not 0 at the same time,

x, y and m are integers greater than or equal to 1, preferably such that the number average molecular weight of formula (1) does not exceed 30,000g/mol and component C) has a viscosity of from 10 to 5000cSt (25 ℃), and

D) saturated or unsaturated, mono-or difunctional C₆-C₃₀In an amount of 0.01 to 3% by weight, preferably 0.05 to 2% by weight, more preferably 0.1 to 1.5% by weight, wherein the metal is selected from the metals of main groups 1, 2 or 3 of the periodic table or zinc.

Preference is also given to fibers which can be prepared by the process according to the invention.

The polyurethaneurea fibers of the invention comprise the polydimethylsiloxanes, alkoxylated polydimethylsiloxanes and fatty acid salts mentioned under B), C) and D), which are present in the fibers in finely divided form (domains) or in dissolved form. The length of the region in the lengthwise direction of the filament in the polyurethaneurea fiber is in particular less than 24um, preferably less than 18um, more preferably less than 15 um. The size of the region in the cross direction of the filament is in particular less than 6um, preferably less than 5um, more preferably less than 4 um. The polyurethane urea fiber of the invention is composed of segmented polyurethane urea polymer. The polymers have a block structure, that is to say the polymers consist of "crystalline" and "amorphous" blocks (also called hard and soft segments).

The polyurethaneurea compositions and polyurethaneurea fibers can be prepared, in particular, from linear homopolymers or copolymers having hydroxyl groups at the molecular ends and a molecular weight of 600-6000g/mol, such as polyether diols, polyester amide diols, polycarbonate diols, or copolymers or mixtures of the abovementioned classes. They may also be based on organic diisocyanates in which a polymeric diol is reacted with the latter to form an isocyanate-terminated prepolymer and a diamine or a mixture of different diamines is used as chain extender, so that the isocyanate-terminated prepolymer reacts with the latter to form a high polymer.

The reaction is usually carried out in an inert polar solvent such as dimethylacetamide, dimethylformamide, N-methylpyrrolidone, and the like. Prepolymers with isocyanate functional groups at the end can also be prepared in melt form.

It is also possible to use polyester diols and/or polyether diols in combination with diols containing tertiary amine groups to prepare prepolymers which bear isocyanate functional groups at the end. For example, N-alkyl-N, N-bishydroxyalkylamines are particularly suitable. Examples of ingredients that may be mentioned include: 4-tert-butyl-3-aza-2, 6-heptanediol, 4-methyl-4-aza-2, 6-heptanediol, 3-ethyl-3-aza-1, 5-pentanediol, 2-ethyl-2-dimethylaminomethyl-1, 3-propanediol, 4-tert-amyl-4-aza-2, 6-heptanediol, 3-cyclohexyl-3-aza-1, 5-pentanediol, 3-methyl-3-aza-1, 5-pentanediol, 3-tert-butylmethyl-3-aza-1, 5-pentanediol and 3-tert-amyl-3-aza-1, 5-pentanediol.

Examples of the organic diisocyanate include 4-4 '-dicyclohexylmethane diisocyanate, isophorone diisocyanate, and 4' -diphenylmethane diisocyanate. Examples of the diamine include ethylenediamine, 1, 2-propylenediamine, 2-methyl-1, 5-diaminopentane, isophorone diamine, 1, 3-diaminocyclohexane, 1-methyl-2, 4-diaminocyclohexane and 1, 2-diaminocyclohexane. The desired molecular weight can be formed by using a small amount of monoamine chain terminator during chain extension, such as diethylamine, dibutylamine or ethanolamine. Using CO₂As a polymerization inhibitor, it can be self-chain-extended.

Polyurethane urea fibres may be prepared according to generally known methods, for example as described in the specifications of US 2929804, US3097192, US 3428711, US 3553290 and US 3555115 and in the specification of WO 9309174.

The polyurethaneurea fibers of the present invention can be used to produce elastic fabrics, knitted goods, hosiery, and other textile products. The invention also provides the use.

According to the process of the invention, the polydimethylsiloxane having a viscosity of from 2 to 20cSt (25 ℃) is present in an amount of from 0.1 to 5% by weight, the alkoxylated polydimethylsiloxane having a molar mass (number average molecular weight) of less than 30,000g/mol and a viscosity of from 10 to 5000cSt (25 ℃) is present in an amount of from 0.1 to 5.0% by weight, the metal salt of a fatty acid is present in an amount of from 0.01 to 3.0% by weight, the% by weight being based on the weight of the polyurethaneurea fiber. After the adjustment of subcomponents B), C) and D), the weight ratio of polydimethylsiloxane to alkoxylated polydimethylsiloxane in the finishing stage is preferably from 2: 1 to 1: 2. The weight ratio of polydimethylsiloxane to fatty acid salt in the finishing stage is preferably from 2: 1 to 1: 2, the data on concentration representing the content of silicone oil or fatty acid salt in the finished elastic spun yarn.

The silicone oil and fatty acid salt may be added to the polyurethaneurea composition at any time desired for the preparation of the composition prior to production of the polyurethaneurea fiber. For example, the silicone oil and the fatty acid salt may be added in the form of a solution to a solution, dispersion or suspension of the other additives. It can be mixed with or injected into the polymer solution upstream relative to the spinneret of the fiber during fiber processing.

The silicone oil and fatty acid salt are preferably added to the polyurethaneurea composition via stock formulations so that the silicone oil and fatty acid salt can be dispersed in a solvent, such as dimethylacetamide, along with other spinning aids. The stock preparation is then mixed with the spinning solution by means of a dynamic or static mixer. The concentration of both silicone oils together with the fatty acid salt in a common stock formulation solution is preferably 10-25% by weight.

The polyurethaneurea fibers are then prepared from the resulting spinning solution by wet spinning or dry spinning, preferably dry spinning. The fibers produced by the process preferably have an individual titer of from 10 to 1280 dtex. The individual denier may be produced in monofilament form or formed from multifilament fibers, for example consisting of 2-200 coalesced individual capillaries. After leaving the spinning shaft, the fibers can be subjected to an external finishing.

Suitable fatty acid salts D) within the scope of the invention are those whose metal is a metal of main groups 1 to 3 of the periodic Table or zinc. The fatty acids are saturated or unsaturated, consist of at least 6 and up to 30 carbon atoms, and are mono-or bifunctional. The fatty acid salts according to the invention are preferably lithium, magnesium, calcium, aluminum and zinc oleates, palmitates or stearates, particularly preferably magnesium, calcium or aluminum stearate.

The polyurethaneurea compositions or polyurethaneurea fibers produced according to the invention may contain, as additives E), delustrants, fillers, antioxidants, dyes, pigments, colorants and stabilizers against heat, light and ultraviolet radiation, chlorinated water, chemical fiber cleaners, especially chlorinated hydrocarbons and anti-steam agents (agaist vapors).

Examples of antioxidants and stabilizers against heat, light and ultraviolet light are sterically hindered phenols, HALS stabilizers (hindered amine light stabilizers), triazines, benzophenones and benzotriazoles. Examples of pigments and matting agents are titanium dioxide, zinc oxide and barium sulphate. Examples of dyes are acid dyes, disperse dyes and organic pigments and also fluorescent whitening agents. Examples of stabilizers which prevent degradation of the fibers by chlorine or chlorine-containing water are zinc oxide, magnesium oxide, calcium magnesium carbonate, calcium magnesium hydroxycarbonate or magnesium aluminum hydroxycarbonate, in particular hydrotalcite. The above-mentioned stabilizers may also be used in combination, and contain an organic or inorganic coating agent.

Detailed Description

The present invention is illustrated in more detail by the following examples, which, however, do not represent any limitation of the present invention.

Examples：

The polyurethaneurea solutions used in the following examples were prepared according to the following method:

in all examples, the polyurethaneurea composition was prepared from a polyester diol having a molecular weight (number average molecular weight) of 2000g/mol, which consists of adipic acid, hexanediol and neopentyl glycol and has been masked by methylene bis (4-phenyl diisocyanate) (MDI, Bayer AG) and then chain extended by a mixture of Ethylenediamine (EDA) and Diethylamine (DEA).

The polyurethaneurea compositions in each example were prepared in the same manner.

For the preparation of the polyurethaneurea composition, 50% by weight of a polyester diol having a molecular weight (number average molecular weight) of 2000g/mol was mixed at 25 ℃ with 1% by weight of 4-methyl-4-aza-2, 6-heptanediol, 36.2% by weight of Dimethylacetamide (DMAC) and 12.8% by weight of MDI, heated to 50 ℃ and held at that temperature for 110 minutes to give an isocyanate-masked polymer having an NCO group content of 2.65% NCO.

After cooling to 25 ℃, 100 parts by weight of the masking polymer was rapidly mixed with a solution of 1.32 parts by weight EDA and 0.04 parts by weight DEA in 187 parts by weight DMAC to form a DMAC solution containing 22% solids of the polyurethaneurea composition. The molecular weight of the polymer was adjusted by adding hexamethylene diisocyanate (HDI, bayer ag) to give a viscosity of 70Pa s (25 ℃).

Following the preparation of the polymer described above, the additive stock formulation was added thereto. The stock formulation consisted of 65.6 wt% DMAC, 11.5 wt% CYANOX^TM1790((1, 3, 5-tris (4-tert-butyl-3-hydroxy-2, 5-dimethylbenzyl) -1, 3, 5-triazine-2, 4, 6- (1H, 3H, 5H) -trione, cytec), 5.7% by weight of TIUNVIN^TM622 (polymer with a molecular weight of approximately 3500g/mol, consisting of succinic acid and 4-hydroxy-2, 2, 6, 6-tetramethyl-1-piperidineethanol, Ciba Geigy), 17.2% by weight of a 22% spinning solution and 0.001% by weight of the dye MAKROVOVIOLET^TMB (Bayer AG). The stock preparation is metered into the spinning solution in such a way that CYANOX^TM1790 content 1.0 wt%, TINUVIN^TM622 was present in an amount of 0.5 wt% (based on the total solids content of the polyurethaneurea composition).

The second stock preparation consisted of 31% by weight of a dioxygenTitanium (TRONOX)^TMTiO₂ R-KB-3，Kerr-McGee Pigments GmbH &Kg), 44.5 wt.% of dimethylacetamide and 24.5 wt.% of 22% of a spinning solution, were added to the first spinning solution in such a way that the titanium dioxide content in the finished yarn was 0.05 wt.% (based on the finished polyurethaneurea fiber).

Additional stock formulation is then added to the spinning solution. These formulations consisted of 5.3 wt.% magnesium stearate (Peter Green), 49.6 wt.% DMAC, 33.8 wt.% 22% spin solution, 6.0 wt.% polydimethylsiloxane, and 5.3 wt.% SILWET^TML7607(Crompton specialities GmbH; ethoxylated polydimethylsiloxane, methyl end-capped, molecular weight 1000g/mol, viscosity 50cSt (25 ℃)), the contents of the components being selected such that the percentage of finished fiber is as

The expression in examples 1 to 3.

Example 1

The content of the additives in the finished polyurethane urea fiber is as follows:

0.28% by weight of magnesium stearate

0.28 wt% SILWE^TML7607

0.32 wt% BAYSILONE^TMOil M5 (polydimethylsiloxane GE Bayer Silicones, viscosity 5cSt (25 ℃ C.)).

Example 2

The content of the additives in the finished polyurethane urea fiber is as follows:

0.19% by weight of magnesium stearate

0.19 wt% SILWET^TM L7607

0.22 wt% BAYSILONE^TMOil M5(GE Bayer Silicones, viscosity 5cSt (25 ℃ C.)).

Example 3Comparative example

The content of the additives in the finished polyurethane urea fiber is as follows:

0.28% by weight of magnesium stearate

0.28 wt% SILWET^TML7607

0.32 wt% BAYSILONE^TMOil M100(GE Bayer Silicones, viscosity 100cSt (25 ℃ C.)).

In examples 1 to 3, the polyurethaneurea composition was spun in a typical dry spinning apparatus to form a filament having a fineness of 11dtex, 4 filaments were combined to form a coagulated yarn of 44dtex, and then wound at a take-up speed of 550 m/min.

The resulting filaments were tested for mechanical properties and characteristics. For this purpose, the relative branch strength (CS) and in particular the elongation at break (EB) can be tested in accordance with DIN53834 Part 1. For this purpose, the tensile test of the elastic filament yarn was carried out under air conditioning. For this purpose, the sample to be prepared is looped around the hook of the measuring head and then placed under a pretension of 0.001cN/dtex in a 10mm loop-shaped clamp. The total grip length was 200 mm. A small piece of aluminum foil is accurately suspended on the level of the light barrier. The slider was moved at a deformation rate of 400%/minute (800mm take-up) until the yarn broke and after the test was finished the slider returned to the original position. Each sample was tested 20 times.

The method for measuring the adhesion of yarn to bobbin includes: firstly, taking off the yarn (except 3 mm) from the bobbin, wherein the bobbin shell is provided with a 500g weight; then, a weight was hung on the yarn, and the weight of the unwinding of the yarn was measured. The adhesion thus determined is a measure of the processability of the bobbin. If the adhesion is too great, the processing of the thin textile product may be more difficult due to yarn tearing. If the adhesion is too low, it is possible that during winding in the dry spinning shaft or during further processing of the bobbin into textile fabrics, the yarn will fall off the bobbin, tear and thus cannot withstand further processing.

The optical uniformity was evaluated by the method described below.

In a first step, 1340 yarns of 44dtex are beamed through 156% pre-draw and 40% post-draw onto two Sectional Warping Beams (SWBs) of an elastic warper (model DSE50/30, from Karl Mayer, Oberhausen).

In a second step, elastic warp knit fabrics were prepared from the above sectional beams together with SWBs of two dtex44/10 polyamides from Snia. A warp knitting machine (Karl Mayer, Oberhausen) of the type HKS 2/E32 was used as the warp knitting machine.

The warp knit fabric thus produced relaxes on the steam board. In the further course of the processing, the shaping was carried out in a tenter frame in the unpressed state with hot air for 40 seconds at a temperature of 195 ℃ and an overfeed of 8%. The set width was 100 cm.

The set fabric was separately passed through a tenter frame and cooled and wound onto a porous dyed beam.

The fabric was dyed blue in a beam dyeing machine according to the following recipe:

0.90％TELON^TMlichtblau RR 182% (Bayer AG; acid dye)

0.05％TELON^TMEchtorange AGT 200% (Byer AG; acid dye)

2.00g/l sodium acetate

1.50％LEVOGAL^TMFTS (Byer AG; leveling agent) and

0.30ml/l of acetic acid.

The closed apparatus was first filled with water before all the auxiliaries were added, in which case there was no circulation of the liquid. After the circulation pump is started and the desired pressure of 2.2-2.0bar is reached, the above-mentioned auxiliaries are added. The liquid is heated at a rate of 1 c/min, the direction of the liquid being chosen such that the outside/inside temperature reaches 80 c and the temperature of the liquid pumped from the inside outwards is higher than 80 c. Once the desired final temperature of 98 ℃ was reached, further treatment was carried out for 60 minutes. Then indirectly cooled to 70 ℃, then continuously flushed with cooled fresh water, and finally flushed again with fresh water.

After dyeing, the dyed beam with the wet fabric is transported to a pad-dyeing machine, passed through the pad-dyeing machine with wash water and then pressed dry uniformly.

The latter intermediate drying was carried out in a perforated drum dryer at a temperature of 120 ℃ and a travelling speed of about 7 m/min. The fabric is laid flat as it enters the porous tumble dryer.

The freshly dried fabric was finally tentered on a tenter frame at a temperature of 150c, a fabric speed of 10 m/min, 5% overfeed, and the smooth finished fabric thus obtained was wound up as it left the tenter frame.

Optical uniformity was evaluated by visually inspecting the finished dyed fabric using transmitted light and reflected light, and the rating (inspection index) was in the range of 1 to 9. For the 44dex polyurethaneurea fiber described here, a rating of 4 represents a very uniform fabric, a rating of 5 indicates that the fabric still meets good uniformity, and a rating of 6 indicates that the fabric meets satisfactory uniformity. If grade 7, the fabric can only be used for special purposes. Fabrics of grades 8 and 9 are not marketable.

Table 1 shows the measured filament properties and the test grades for evaluating the optical homogeneity.

TABLE 1

Yarn data are compared to a table evaluating inspection grade for optical uniformity:

example number	Fineness (dtex)	CS(cN/dtex)	EB(％)	Adhesion (cN)	Grade of inspection
						1	43.6	1.24	417	0.05	n.d.
2	45.7	1.21	420	0.23	5.0
						3 (comparative example)	45.2	1.21	402	0.23	5.0

CS: relative count intensity, EB: elongation at break

As shown in the examples, the addition of BAYSILONE-based^TMStock preparation formulation of oil M5 and addition of BAYSILONE-based^TMPreparation of oil M100Compared with the material preparation, the adhesion force is obviously changed. Thus, the addition of BAYSILONE-based^TMStock preparation formulation of oil M5 and addition of BAYSILONE-based^TMThe adhesion was greatly reduced compared to the stock formulation for oil M100. Thus, the use of BAYSILONE-based^TMThe effect of magnesium stearate as an anti-adherent was significantly enhanced when the stock formulation of oil M5 was used. Using BAYSILONE-based^TMIn the case of the stock formulation of oil M100, the effect of magnesium stearate is reduced due to agglomeration of the formulation. By reducing BAYSILONE in the spinning solution^TMThe content of oil M5 is easy to adjust the adhesion to BAYSILONE-based^TMLevel of stock formulation for oil M100. The spinning solution contains BAYSILONE-based^TMThe preparation of oil M5 resulted in an increased filter life and hence increased productivity during spinning.

The evaluation of the relative Count Strength (CS) and optical homogeneity is independent of the stock preparation formulation and remains constant at a constant level.

In a series of experiments on examples 4-9, stock formulations were formulated using different polydimethylsiloxanes and alkoxylated polydimethylsiloxanes. The stock formulation consisted of 5.3 wt% magnesium stearate (peterggreven), 49.6 wt% DMAC, 33.8 wt% 30% spinning solution, 6.0 wt% polydimethylsiloxane, and 5.3 wt% alkoxylated polydimethylsiloxane.

The stock formulations were stored at 25 ℃ and 50 ℃ and evaluated for homogeneity immediately after the preparation and after 24 hours of standing, respectively.

The evaluation of the homogeneity of the stock formulation is shown in table 2.

The 30% spinning solution used for the formulation of the stock preparation was prepared from a polyether diol consisting of polytetrahydrofuran (PTHF, e.g.Terathane 2000 from DuPont) and having an average molecular weight (number average) of 2000 g/mol. The diol was masked with methylene bis (4-phenyl diisocyanate) (MDI, Bayer AG) in a molar ratio of 1: 1.65 and then chain extended by a mixture of Ethylenediamine (EDA) and Diethylamine (DEA) in a weight ratio of 97: 3 in Dimethylacetamide (DMAC). The ratio of the amount of chain extender and chain terminator to unreacted isocyanate in the prepolymer was 1.075. The solids content of the resulting polyurethaneurea solution was 30% by weight.

The additive stock formulation is then mixed with the polymer. Stock formulation was prepared from 62.7 wt% Dimethylacetamide (DMAC), 10.3 wt% CYANOX^TM1790((1, 3, 5-tris (4-tert-butyl-3-hydroxy-2, 5-dimethylbenzyl) -1, 3, 5-triazine-2, 4, 6- (1H, 3H, 5H) -trione, cytec), 27.0% by weight of 30% spinning solution and 0.001% by weight of the dye MAKROXIVIOLET^TMB (Bayer AG). The stock formulation is added to the polyurethaneurea composition in a manner such that CYANOX^TMThe content of 1790 is 1.0% by weight, based on the total solids content.

Example 4

5.3% by weight of magnesium stearate

6.0 wt.% BAYSILONE^TMOil M3(GE Bayer Silicones, viscosity 3cSt (25 ℃ C.)).

5.3 wt% SILWE^TML7607(Crompton Specialities GmbH; ethoxylated polydimethylsiloxane, methyl-terminated, molecular weight 1000g/mol, viscosity 50cSt (25 ℃ C.)).

Example 5

5.3% by weight of magnesium stearate

6.0 wt.% BAYSILONE^TMOil M5(GE Bayer Silicones, viscosity 5cSt (25 ℃ C.)).

5.3 wt% SILWE^TML7607(Crompton Specialities GmbH; ethoxylated polydimethylsiloxane, methyl-terminated, molecular weight 1000g/mol, viscosity 50cSt (25 ℃ C.)).

Example 6Comparative example

5.3% by weight of magnesium stearate

6.0 wt.% BAYSILONE^TMOil M100(GE Bayer Silicones, viscosity 100cSt (25 ℃ C.)).

5.3 wt% SILWE^TML7607(Crompton Specialities GmbH; ethoxylated polydimethylsiloxane, methyl-terminated, molecular weight 1000g/mol, viscosity 50cSt (25 ℃ C.)).

Example 7

5.3% by weight of magnesium stearate

6.0 wt.% BAYSILONE^TMOil M5(GE Bayer Silicones, viscosity 5cSt (25 ℃ C.)).

5.3 wt% SILWE^TML77(Crompton Specialities GmbH; ethoxylated polydimethylsiloxane, methyl-terminated, molecular weight 600g/mol, viscosity 20cSt (25 ℃ C.)).

Example 8

5.3% by weight of magnesium stearate

6.0 wt.% BAYSILONE^TMOil M5(GE Bayer Silicones, viscosity 5cSt (25 ℃ C.)).

5.3 wt% SILWE^TML7608(Crompton Specialities GmbH; ethoxylated polydimethylsiloxane, hydroxyl-terminated, molecular weight 600g/mol, viscosity 35cSt (25 ℃ C.)).

Example 9Comparative example

5.3% by weight of magnesium stearate

6.0 wt.% BAYSILONE^TMOil M100(GE Bayer Silicones, viscosity 100cSt (25 ℃ C.)).

5.3 wt% SILWE^TML7608(Crompton Specialities GmbH; ethoxylated polydimethylsiloxane, hydroxyl-terminated, molecular weight 600g/mol, viscosity 35cSt (25 ℃ C.)).

TABLE 2

Stock preparation uniformity tabulation comparison:

example number	Uniformity after formulation	25℃*Homogeneity after 24 hours	50℃*Homogeneity after 24 hours
				4	Is very good	Is very good	Is very good
5	Is very good	Is very good	Is very good
				6 (comparative example)	Phase separation	Phase separation	Suspected aggregation
7	Is very good	Is very good	Is very good
				8	Is very good	Is very good	Is very good
9 (comparative example)	Phase separation	Phase separation	Agglomeration

^*Storage temperature of stock preparation

As shown in the examples, the homogeneity of the stock formulation is strongly dependent on the viscosity of the polydimethylsiloxane used. If a higher viscosity polydimethylsiloxane is mixed with BAYSILONE^TMThe use of oil M100 together results in phase separation and a decrease in the homogeneity of the stock formulation. In such stock formulations, coagulation also occurs at storage temperatures of 50 ℃, a phenomenon which frequently occurs when preparing polyurethaneurea compositions for the production of polyurethaneurea fibers. In the production of polyurethaneurea fibers, the formation of coacervation leads to a decrease in the effectiveness of magnesium stearate as an agent for adjusting adhesion, which changes the adhesion during spinning and shortens the service life of the filter. Therefore, it is impossible to obtain constant textile fiber data (adhesion) during continuous production of the polyurethaneurea fiber due to the coagulation phenomenon. At the same time, the productivity of the spinning process is reduced.

Claims (25)

1. A process for producing polyurethaneurea fibers by a dry or wet spinning process comprising preparing a polyurethaneurea spinning solution, spinning the spinning solution using a spinneret, forming a yarn under the spinneret by drying or removing the spinning solvent in a coagulation bath, finishing and optionally twisting, and winding the spun fiber, wherein prior to spinning

B) Polydimethylsiloxane, in an amount of 0.1 to 5% by weight, having a viscosity of 2 to 20cSt (25 ℃),

C) alkoxylated Polydimethylsiloxane (PDMS) corresponding to general formula (1), in an amount of 0.1 to 5% by weight,

in the above formula

PE is a monovalent radical-CH₂-CH₂-CH₂-O(eo_v/po_w)_mZ wherein

eo ═ ethylene oxide, po ═ propylene oxide, Z is hydrogen or C₁-C₆The alkyl group of (a) is,

v and w are integers of 0 or more and are not 0 at the same time,

x, y and m are integers greater than or equal to 1, preferably such that the number average molecular weight of the compound of formula (1) does not exceed 30,000g/mol and the viscosity of the C) component is from 10 to 5000cSt (25 ℃),

D) saturated or unsaturated, mono-or difunctional C₆-C₃₀In an amount of 0.01 to 3.0% by weight, wherein the metal is selected from the metals of main groups 1, 2 or 3 of the periodic table or is zinc,

based on the weight of the finished polyurethaneurea fiber.

2. The process according to claim 1, wherein said spinning process is a dry spinning process.

3. The method according to claim 1, wherein the polydimethylsiloxane content is from 0.2 to 3% by weight.

4. A method according to claim 3, wherein the polydimethylsiloxane content is from 0.3 to 2% by weight.

5. The method according to claim 1, wherein the alkoxylated polydimethylsiloxane content is from 0.2 to 3% by weight.

6. The method according to claim 5, wherein the alkoxylated polydimethylsiloxane content is from 0.3 to 2% by weight.

7. The process according to claim 1, wherein the metal salt is present in an amount of 0.05 to 2% by weight.

8. The process according to claim 7, wherein the metal salt is present in an amount of 0.1 to 1.5% by weight.

9. The method according to claim 1, wherein the content of the polyurethaneurea in the spinning solution is adjusted so that the finished polyurethaneurea fiber is obtained to contain 99.7 to 65% by weight of the polyurethaneurea.

10. The method of claim 9 wherein said fibers comprise 99.5 to 80 weight percent polyurethane.

11. The method of claim 10 wherein said fibers comprise 99 to 85 weight percent polyurethane.

12. The process according to claim 1, wherein components B), C) and D) are added to the spinning solution in such amounts that the weight ratio of polydimethylsiloxane B) to alkoxylated polydimethylsiloxane C) in the finished fiber is from 2: 1 to 1: 2 and the weight ratio of polydimethylsiloxane B) to fatty acid salt D) is from 2: 1 to 1: 2.

13. The process according to claim 1, wherein polydimethylsiloxane B), alkoxylated polydimethylsiloxane C) and fatty acid salt D) are added to the spinning solution in the form of a stock formulation solution containing 10 to 25% by weight, based on the total amount of components B), C) and D), of the spinning solvent.

14. The method according to claim 1, wherein the finished spun fiber has a denier of 10 to 1280 dtex.

15. A polyurethaneurea fiber comprising:

A) a polyurethaneurea polymer in an amount of 99.7 to 65% by weight,

B) polydimethylsiloxane, in an amount of 0.1 to 5% by weight, having a viscosity of 2 to 20cSt (25 ℃),

C) alkoxylated Polydimethylsiloxane (PDMS) corresponding to general formula (1), in an amount of 0.1 to 5% by weight,

wherein

PE is a monovalent radical-CH₂-CH₂-CH₂-O(eo_v/po_w)_mZ，

eo represents an ethylene oxide, and the reaction product of ethylene oxide,

po represents propylene oxide, and

z is hydrogen or C₁-C₆The alkyl group of (a) is,

v and w are integers of 0 or more and are not 0 at the same time,

x, y and m are integers greater than or equal to 1, preferably such that the number average molecular weight of the compound of formula (1) does not exceed 30,000g/mol and the viscosity of component C) is from 10 to 5000cSt (25 ℃),

D) saturated or unsaturated, mono-or difunctional C₆-C₃₀In an amount of 0.01 to 3% by weight, wherein the metal is selected from the metals of main groups 1, 2 or 3 of the periodic Table or is zinc, and

E) an additive in an amount of 0 to 20% by weight,

wherein the polydimethylsiloxane, alkoxylated polydimethylsiloxane and fatty acid salt are finely dispersed or dissolved in the fibers.

16. The polyurethaneurea fiber of claim 15, wherein the polyurethaneurea polymer content is 99.5 to 80 wt%.

17. The polyurethaneurea fiber of claim 16, wherein the polyurethaneurea polymer content is 99-85% by weight.

18. The polyurethaneurea fiber of claim 15, wherein the polydimethylsiloxane content is 0.2 to 3% by weight.

19. A polyurethaneurea fiber according to claim 18, wherein the polydimethylsiloxane content is 0.3 to 2% by weight.

20. The polyurethaneurea fiber of claim 15, wherein the alkoxylated polydimethylsiloxane content is from 0.2 to 3 weight percent.

21. A polyurethaneurea fiber according to claim 20, wherein the alkoxylated polydimethylsiloxane content is from 0.3 to 2% by weight.

22. The polyurethaneurea fiber of claim 15, wherein the metal salt is present in an amount of 0.05 to 2 wt.%.

23. The polyurethaneurea fiber of claim 22, wherein the metal salt is present in an amount of 0.1 to 1.5 wt%.

24. The polyurethaneurea fiber of claim 15, wherein the additive is present in an amount of 0 to 15 weight percent.

25. An elastic fabric, knit product or hosiery comprising the polyurethaneurea fiber of claim 15.