Polyurethane urea fiber or film and its preparation method

Abstract

The present invention relates to a polyurethane urea fiber or film having high elongation, low tensile stress, low hysteresis loss and excellent elastic recovery at the same time. The elastic polyurethane fiber or film of the present invention is formed from a copolymer glycol, a diisocyanate, a chain extender and optionally a chain terminator. The polyurethane fiber is characterized in that its hard segment content is within the range of 8.0 to 13.0 wt%.

Description

[Technical field]

[0001] The present invention relates to a polyurethaneurea fiber or film and a method for preparing the same.The present invention further relates to a polyurethaneurea fiber or film having high elongation, low tensile stress, excellent elastic recovery and low hysteresis loss. [Background technology]

[0002] Elastic polyurethane urea fibers have considerable extensibility combined with outstanding elasticity and high contraction force. Due to this combination of outstanding properties, they are widely used in underwear, outerwear, sportswear, swimwear, socks, girdles, medical products, hygiene products, etc. Such elastic polyurethane fibers and the process for producing them are described in U.S. Pat. Nos. 5,541,280, 6,692,828, EP 1,401,946, DE 19931,255, JP 63-219620 A and U.S. Pat. No. 6,503,996.

[0003] Disadvantages of these elastic polyurethaneurea fibers include, for some applications, insufficient elongation at break (which therefore allows incorporation into textiles only under relatively low pretension) and still substantial increase in tension at customary garment elongations of 200-400% (which can lead to uncomfortable pressure, especially at high elastic polyurethane fiber contents, e.g. as athletic wear, medical bandages, cuffs, socks or baby diapers).

[0004] While polyurethaneurea fibers exhibiting extremely high breaking elongation or stretch with low stretch stress can usually provide soft stretch, low recovery can cause bulging or ragging after repeated large stretching or bending, such as in leotards, athletic wear, degrading the comfort and aesthetics of the associated article.

[0005] A polyurethaneurea elastic fiber with balanced performance in terms of high elongation, low tensile stress, good elastic recovery and low hysteresis loss is required for soft-fitting garments.

[0006] US Patent No. 5,000,899A discloses a process using a copolymer of tetrahydrofuran and 3-methyltetrahydrofuran to prepare polyurethaneurea fibers in combination with a diamine mixture, which shows good thermosetting properties, but does not mention the improvement of elongation, elastic recovery and tensile stress.

[0007] US Patent No. 5,879,799A discloses a process using a copolymer of polyalkylene ether glycols consisting of different alkylene ethers containing 2 to 10 carbon atoms to make polyurethaneurea fibers with balanced performance among heat resistance, abrasion resistance, elongation and low temperature performance, but the tensile stress of the fibers is high.

[0008] US20090182113A discloses a process using copolymers of polytetrahydrofuran glycol and isophthalic acid or isophthalic acid derivatives to make polyurethaneurea fibers, but the fibers produced therefrom do not show improvement in the bulging or ragging problems associated with high stretchability and low tensile stress, and furthermore, due to the lack of polymer composition design, the polyurethaneurea solutions made therefrom show poor polyurethane viscosity stability and poor spinnability due to gelation, even at 20 wt% polymer solids, and / or other side reactions are expected.

[0009] Therefore, there is a need to provide polyurethaneurea fibers or films that have high elongation, low tensile stress, excellent elastic recovery and low hysteresis loss. Summary of the Invention [Problem to be solved by the invention]

[0010] An object of the present invention is to provide a polyurethaneurea fiber or film having a balanced performance among high elongation, low tensile stress, excellent elastic recovery and low hysteresis loss. [Means for solving the problem]

[0011] Surprisingly, it has been found that the above objectives can be achieved by the following embodiments.

[0012] 1. A polyurethaneurea fiber or film comprising a hard segment content (HS) of 8.0 to 13.0 wt.%, wherein the hard segment content is determined by the following formula:

number

[0013] 2. The polyurethane urea fiber or film according to item 1, wherein the hard segment content of the polyurethane urea fiber or film is within the range of 8.0 to 12.5% ​​by weight, the urethane portion has a number average molecular weight Mn (urethane) of 5000 to 9000 g / mol, and the urea portion has a number average molecular weight Mn (urea) of 500 to 900 g / mol, and preferably the hard segment content of the polyurethane urea fiber or film is within the range of 8.5 to 12.5% ​​by weight, the urethane portion has a Mn (urethane) of 5500 to 8500 g / mol, and the urea portion has a Mn (urea) of 550 to 850 g / mol.

[0014] 3. The polyurethaneurea fiber or film according to claim 1 or 2, wherein the copolymer glycol is prepared from at least one aromatic carboxylic acid and / or its anhydride and / or its ester and at least one polymeric glycol.

[0015] 4. The polyurethane urea fiber or film according to any one of items 1 to 3, wherein the number average molecular weight (Mn) of the copolymer glycol is 500 to 5000 g / mol, preferably 1800 to 4000 g / mol, more preferably 2000 to 3500 g / mol.

[0016] 5. The polyurethane urea fiber or film according to item 3 or 4, wherein the content of the aromatic carboxylic acid and / or its anhydride and / or its ester moiety in the copolymer glycol is 6.0 to 20.0% by weight.

[0017] 6. The polyurethane urea fiber or film according to any one of items 3 to 5, wherein the aromatic carboxylic acid and / or its anhydride and / or its ester is selected from isophthalic acid, dimethyl isophthalate, phthalic acid, terephthalic acid, and their anhydrides, preferably isophthalic acid, dimethyl isophthalate, and mixtures thereof, more preferably isophthalic acid.

[0018] 7. The polyurethaneurea fiber or film according to any one of claims 1 to 6, wherein the polymer glycol is selected from the group consisting of polytetrahydrofuran glycol, polyesterol, polyetherol, polycaprolactone and / or mixtures thereof, preferably the polymer glycol comprises polytetrahydrofuran glycol, more preferably the polymer glycol is polytetrahydrofuran glycol.

[0019] 8. A process for producing the polyurethane urea fiber according to any one of claims 1 to 7, comprising: a) reacting a copolymer glycol with at least one diisocyanate to obtain a urethane prepolymer containing isocyanates at both ends; b) adding a chain extender and optionally a chain terminator to the above urethane prepolymer in an inert solvent to obtain a polyurethane solution; c) dry spinning the polyurethane solution to obtain polyurethane urea fibers. A process including.

[0020] 9. The process of paragraph 8, wherein the diisocyanate comprises 4,4'-methylene diphenyl diisocyanate, preferably greater than 60% 4,4'-methylene diphenyl diisocyanate, more preferably greater than 80% 4,4'-methylene diphenyl diisocyanate, and most preferably greater than 95% 4,4'-methylene diphenyl diisocyanate.

[0021] 10. The process of paragraph 8 or 9, wherein the chain extender comprises an aliphatic diamine having two hydrogen atoms reactive with isocyanate groups, preferably the aliphatic diamine is selected from 1,2-ethylenediamine, 1,2-propylenediamine, 1,3-propylenediamine, 1,4-butanediamine, 1,5-pentanediamine, 1,4-cyclohexanediamine and mixtures thereof, more preferably the aliphatic diamine is 1,2-ethylenediamine.

[0022] 11. The process according to any one of clauses 8 to 10, wherein the chain terminator is an alkyl alcohol and / or a dialkylamine, preferably, the chain terminator is selected from n-butanol, cyclohexanol, ethanolamine, diethanolamine, N,N-diethylamine, N,N-dibutylamine or mixtures thereof.

[0023] 12. The process according to any one of paragraphs 8 to 11, wherein amines other than the chain extender and chain terminator are added together with the chain extender, preferably such amines other than the chain extender and chain terminator are diethylene-triamine and / or diethanolamine.

[0024] 13. Use of the polyurethaneurea fiber according to any one of claims 1 to 7 for making a fabric. [Brief description of the drawings]

[0025] [Figure 1]1 shows the HNMR spectrum of the chemical shifts of the methylene groups in the 4,4′-methylenediphenyldiisocyanate (4,4′-MDI) moiety of Example 2. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0026] Unless otherwise defined, all technical and scientific terms used herein have the meaning commonly understood by one of ordinary skill in the art to which this invention belongs. As used herein, the following terms have the following meanings ascribed to them unless otherwise specified:

[0027] The indefinite articles "a," "an," and "the" refer to one or more of the kind designated by the term following the article.

[0028] In the context of this disclosure, any specific values ​​recited in relation to characteristics (including specific values ​​recited within a range as endpoints) can be recombined to form new ranges.

[0029] It will be understood that the features of the subject matter of the invention described above and not yet described below can be used not only in the specific combinations shown, but also in other combinations, without departing from the scope of the invention.

[0030] In one embodiment, the polyurethaneurea fibers of the present invention are prepared from a copolymer glycol, at least one diisocyanate, at least one chain extender, and optionally a chain terminator.

[0031] The copolymer glycols of the present invention are essentially prepared by condensing a polymer glycol with at least one aromatic carboxylic acid and / or its anhydride and / or its ester. In a preferred embodiment, said at least one aromatic carboxylic acid and / or its anhydride and / or its ester are transesterified with isopropyl orthotitanate in the presence of a transesterification catalyst, such as titanium tetrabutyl orthotitanate, tetraisopropyl orthotitanate, dibutyltin laurate, dibutyltin oxide, tin octoate, tin chloride, tin oxide, sulfuric acid, para-toluenesulfonic acid, potassium hydroxide, sodium methoxide, titanium zeolite, lipase or hydrolase, preferably tetrabutyl orthotitanate (comparison with each other), immobilized on a support. The distillate is removed from the reaction system in a multi-stage operation at various pressure levels, at least one reaction stage being under atmospheric pressure and at least one reaction stage being under reduced pressure, and the process includes heating the reaction mixture in two or more phases in an atmospheric pressure reaction stage, the heating phase being interrupted by at least one phase in which the temperature is kept constant. The preparation process of the copolymer glycol of the present invention is disclosed in US Patent Application Publication No. 2012 / 0059143, which is incorporated herein by reference below, in particular in paragraphs 0011-0028 and Example 1 thereof.

[0032] Substantially means that the major components of the copolymer glycol are aromatic carboxylic acids and / or their anhydrides and / or their esters and at least one polymeric glycol, although other diacids may also be incorporated during copolymerization, provided that such additional components do not seriously adversely affect the performance of the elastic fibers.

[0033] Polymeric glycols as used herein include, but are not limited to, polyesterols having two hydroxy groups per molecule, and / or polyetherols, and / or polycaprolactones, such as polytetrahydrofuran glycol and its derivatives, polyethers and copolyethers, such as polytetrahydrofuran glycol, poly(tetrahydrofuran-co-ethylene ether) glycol, polycarbonate glycols, such as poly(pentane-1,5-carbonate) glycol, and poly(hexane-1,6-carbonate) glycol, and poly(ethylene-co-propylene adipate) glycol, and polyesterols, such as polyesters of adipic acid, 1,4-butanediol, and neopentyl glycol, polyesters of adipic acid, 1,4-butanediol, and 1,6-hexanediol, polyesters of adipic acid and 1,4-butanediol, polyesters of adipic acid and 1,6-hexanediol, polyesters of dodecanedioic acid and neopentyl glycol, or polyesters of sebacic acid and neopentyl glycol. Preference is given to using polycaprolactone, polyesters of adipic acid and 1,4-butanediol, polytetrahydrofuran glycol, polyesters of adipic acid, butanediol and neopentyl glycol, polyesters of adipic acid, 1,4-butanediol and 1,6-hexanediol, polyesters of adipic acid and 1,6-hexanediol, polyesters of dodecanedioic acid and neopentyl glycol or polyesters of sebacic acid and neopentyl glycol or mixtures thereof. Particular preference is given to the use of polytetrahydrofuran glycol, alone or in a mixture with further glycols, in particular alone.

[0034] When polytetrahydrofuran glycol is used alone as the polymer glycol, its number average molecular weight Mn is preferably 200 to 2500 g / mol, more preferably 200 to 2100 g / mol, and most preferably 500 to 1500 g / mol. When polytetrahydrofuran glycol has an Mn of less than 200 g / mol, the hysteresis loss of the resulting polyurethaneurea fiber or film is poor, and when polytetrahydrofuran glycol has a number average molecular weight exceeding 1500 g / mol, it exhibits an unsatisfactorily high tensile stress.

[0035] In one embodiment, the aromatic carboxylic acid and / or its anhydride and / or its ester moiety is in the range of 6-20 wt %, depending on the starting molecular weight of the polymeric glycol and the target Mn of the copolymeric glycol. The aromatic carboxylic acid and / or its anhydride and / or its ester moiety in the copolymeric glycol is defined below as a modifier. The molecular weight cutoff of the modifier moiety is approximately 1 mole H when isophthalic acid, an example of a diacid, is used to make the copolymer. 2 Where O is defined as the residue portion of a diacid subtracted, and when a diester, such as dimethyl phthalate, is used to make the copolymer, one mole of dimethyl ether is subtracted, and in either case the molecular weight cut off of the modifier portion is 148 g / mole.

[0036] In another embodiment, the copolymer glycol has a number average molecular weight Mn of 500 to 5000 g / mol, preferably 1800 to 4000 g / mol, more preferably 2000 to 3500 g / mol.

[0037] Suitable diisocyanates for the present invention include, but are not limited to, aromatic diisocyanates such as 4,4'-methylenediphenyl diisocyanate (4,4'-MDI), naphthylene diisocyanate (NDI), 2,4- or 2,6-toluene diisocyanate (TDI), 1,4-phenyl diisocyanate, and aliphatic diisocyanates such as 4,4'-diisocyanato-dicyclohexylmethane (HMDI), isophorone diisocyanate. These may be used individually or in combination. Aromatic diisocyanates, especially 4,4'-MDI, are preferred. 2,4'-methylenediphenyl diisocyanate (2,4'-MDI) may be used in combination with 4,4'-MDI with the mole percentage of 2,4'-MDI being less than 40%, preferably less than 20%, more preferably less than 5% of the total diisocyanate.

[0038] Suitable chain extenders for the present invention include compounds having two isocyanate-reactive hydrogen atoms and a molecular weight of less than 500 g / mol. Such substances are described, for example, in "Kunststoffhandbuch, 7, Polyurethane", Carl Hanser Verlag, 3rd edition 1993, Chapter 3.4.3. (e.g. ethylenediamine, 1,2-propylenediamine, 1,3-propylenediamine, 1,4-butanediamine, 1,5-diaminopentane, hydrazine, m-xylylenediamine, p-xylylenediamine, 1,4-cyclohexanediamine, 1,3-cyclohexanediamine, 1,3-diamine-4-methylcyclohexane, 1-amino-3-aminoethyl-3,3,5-trimethylcyclohexane (isophoronediamine), 1,1'-methylenebis(4,4'-diamino-hexane)toluenediamine, piperazine, ethylene glycol, 1,2-propanediol, 1,3-propanediol, 1,4-butanediol, 1,5-pentanediol, 1,6-hexanediol or mixtures thereof). Particularly preferred are diamines, such as ethylenediamine, 1,2-propylenediamine, 1,3-propylenediamine, 1,4-butanediamine, 1,5-diaminopentane, hydrazine, m-xylylenediamine, p-xylylenediamine, 1,4-cyclohexanediamine, 1,3-cyclohexanediamine, 4-methylcyclohexane-1,3-diamine and isophoronediamine, diaminohexane and toluenediamine, as well as mixtures thereof, in particular ethylenediamine, used alone or in combination with the abovementioned diamines in a molar ratio of 80% or more.

[0039] Optionally, a chain terminator can also be used in the preparation of the polyurethaneurea fiber or film of the present invention.Suitable chain terminators for the present invention include secondary amines such as diethylamine, dibutylamine, dicyclohexylamine or primary amines such as ethanolamine or primary alcohols such as n-butanol (alone or as a mixture).Preferably, the chain terminator is a monofunctional amine.Specific amines can be used, examples of which are diethylene-triamine or diethanolamine.

[0040] The preparation of the polyurethaneurea polymer in the present invention can be carried out by the following process.

[0041] First, the copolymer glycol is capped with a diisocyanate with a molar ratio of diisocyanate to polymer glycol ranging from 1.2 to 3.0, preferably ranging from 1.5 to 2.3. To adjust the hard segment content, the diisocyanate can be added to the reactor in stages, i.e., both the soft segment portion and the hard segment portion can be stretched by dividing the diisocyanate into the reactor, which is advantageous for the stretchability and recovery of the polyurethane polymer.

[0042] When all the OH groups of the polymer glycol are converted into urethane groups, as indicated by the residual NCO content by weight reaching the theoretical NCO% content, a urethane prepolymer is obtained, which can be chain extended by diamines in a solvent such as N,N-dimethylacetamide (DMAC), N,N-dimethylformamide (DMF), etc. The theoretical NCO% content by weight when the prepolymerization is completed is calculated in the present invention as follows:

number

[0043] Mn(copolymer) is the number average molecular weight of the copolymer glycol or other polymer glycol used to prepare the polyurethaneurea polymer of the present invention as tested by the method of ASTM 1899-2016.

[0044] Chain terminators such as diethylamine or n-butanol can be used to adjust the molecular weight of the polyurethaneurea polymer within the processing range by processes well known in the art.

[0045] During the prepolymerization process of the copolymer glycol with the diisocyanate, it is necessary to monitor the NCO% that reacts with amine after the OH group of the copolymer glycol is completely converted to a urethane group, and adjust the effective hard segment content to within the range of 8.0-13.0 wt%, preferably 8.0-12.5 wt%, more preferably 8.5-12.5 wt%. Otherwise, the NCO% content will further decrease during and / or after the prepolymerization of the copolymer glycol with the diisocyanate, resulting in undesirable gelation and / or a decrease in the effective hard segment content, which will deteriorate the spinnability and / or stress-strain performance and recovery of the fiber.

[0046] Amine capped NCO% is the titrated NCO% content after completion of prepolymerization of diisocyanate with copolymeric or polymeric glycol and before chain extension, where NCO capped prepolymer reacts with amine, as tested by method ASTM D2572-19. Side reactions during prepolymerization of polymeric glycol with isocyanate and / or during dissolution of prepolymer in solvents such as DMAC or DMF are well known to degrade spinning and elastic performance of spandex.

[0047] The hard segment content of the present invention is defined as follows.

number

[0048] In the present invention, hard segment content is tested by HNMR method.When hard segment content is more than 13.0wt%, the polyurethaneurea polymer obtained shows unsatisfactorily high tensile stress, for example, more than 10MPa, and further causes gelation and unstable processability.On the other hand, when hard segment content is less than 8.0wt%, the polyurethaneurea polymer obtained shows unpleasantly low recovery force and low elastic recovery rate, which further causes bagging or ragging in clothing article after repeated stretching or bending.

[0049] Assuming that the hard segment content is within the range of 8.0 to 13.0% by weight, Mdo, ie, Mn of the copolymer glycol, is preferably within the range of 1800 to 4000 g / mol, more preferably 2000 to 3500 g / mol.

[0050] The fully reacted solution is subsequently spun to form fibers. Any spinning process can be used by which the fibers of the present invention can be produced. Such spinning processes are described, for example, in "Kunststoffhandbuch, 7, Polyurethane", Carl Hanser Verlag, 3rd edition 1993, Chapter 13.2. These include dry spinning or wet spinning processes, preferably dry spinning processes. In the spinning process, the spinning solution containing the polyurethaneurea of ​​the present invention is spun through a spinneret die to form threads. The polyurethaneurea fiber of the present invention is obtained after removing the spinning solvent, for example by drying.

[0051] The polyurethaneurea fiber of the present invention may further comprise additives. Any additive known for polyurethaneurea fibers may be used herein. For example, matting agents, fillers, antioxidants, dyes, pigments, dye enhancers, such as Methacrol 2462B, and resistance to heat, light, UV radiation, chlorinated water, and gas odors and air pollution, such as NO or NO 2 Stabilizers against the action of antioxidants, heat, light or UV radiation may be included. Examples of stabilizers against antioxidants, heat, light or UV radiation are sterically hindered phenols, such as Irganox® 245 or Cyanox® 1790, hindered amine light stabilizers, stabilizers from the group of triazines, benzophenones and benzotriazoles. Examples of pigments and matting agents are titanium dioxide, magnesium stearate, zinc oxide and barium sulfate. Examples of stabilizers against fiber degradation by chlorine or chlorinated water are zinc oxide, magnesium oxide or coated or uncoated magnesium aluminum hydroxycarbonates, such as hydrotalcite or huntite.

[0052] The polyurethaneurea fibers of the present invention are useful in the production of elastic fabrics, such as wovens, knits, and the like.

[0053] The following are methods for measuring the Mn of the urethane portion, the Mn of the urea portion, and the hard segment content of the polyurethaneurea film of the present invention prepared with 4,4'-MDI as the diisocyanate.

[0054] Figure 1 shows an exemplary HNMR spectrum measured under the above conditions. In Figure 1, peak P1 at 3.87 ppm and 4.9 cm in height represents methylene groups in 4,4'-MDI moieties capped at both ends with urethane groups, peak P2 at 3.84 ppm and 9.0 cm in height represents methylene groups in 4,4'-MDI moieties capped at one end with a urethane group and at the other end with a urea group, and peak P3 at 3.80 ppm and 2.6 cm in height represents methylene groups in 4,4'-MDI moieties capped at both ends with urea groups. The peak heights, shown in Figure 1 as numbers in cm, are used as an indication of the molar amount of moieties in the polyurethane polymer.

[0055] The soft segment Mn (urethane) of the present invention is Mn(urethane)=2*P1 / P2*(Mdi+Mdo)+Mdo(3) The hard segment Mn (urea) of the present invention is calculated by: Mn(urea)=2*P3 / P2*(Mda+Mdi)+Mda+2Mdi(4) where Mdi is the molecular weight of the diisocyanate, for 4,4'-MDI Mdi=250.26, Mda is the molecular weight of the chain extender, and if a mixed chain extender is used Mda is the averaged Mn of the mixed chain extender.

[0056] Mdo is the number average molecular weight of the copolymeric glycol or other polymeric glycol used in the present invention. The Mdo of the polyurethaneurea polymer is tested by HNMR as follows.

number

[0057] In the present invention, the test methods for various properties are as follows:

[0058] Method for determining Mn of urethane moiety, urea moiety and hard segment content. Polyurethane urea fiber or film sample was cut into small pieces and dissolved in deuterated dimethylformamide. The equipment and measurement conditions are summarized below. Measurement equipment: Bruker AVANCE NEO 600MHz (equipped with DCH Cryo probe) Observed nucleus: IH Total: 128 Measurement temperature: 25℃ Measured concentration: 2.0% by weight Chemical shift standard: tetramethylsilane (0 ppm)

[0059] Stress-strain performance evaluation For handling and reproducibility, the mechanical properties of polyurethaneurea were measured on the films. For this purpose, the prepared polyurethaneurea solutions were cast on precisely horizontally aligned glass plates and heated under slow N 2 The membranes were converted by drying in a flow stream for 48 h. The amount and concentration of the solutions as well as the area of ​​the plates were matched to each other to produce membranes with a thickness of about 0.20-0.26 mm. The membranes were mechanically tested according to a) ISO 037:2005 (tensile test) and b) DIN 53835-2:1981 (hysteresis loss).

[0060] The trends observed in the membranes are essentially identical to those in the fibers, and the effects of polymer chain orientation seen in the fibers and imparted by the spinning process are not reflected in the membranes. These differences are not intended to interfere with the spirit of the present invention.

[0061] The elastic properties of the specimens are tested by a 1KN Zwick / Roell Z2.5 equipped with a 1kN KAF-TC force sensor.

[0062] Breaking elongation: According to ISO37:2005, take a film sample of standard shape and size of polyurethaneurea, and vary the length of the stretched sample, expressed as % of the original length when the sample breaks. The breaking elongation of the polyurethaneurea film according to the present invention is more than 500%, preferably more than 600%, more preferably more than 700%.

[0063] Tensile stress: take a film sample of standard shape and size of polyurethaneurea according to ISO37:2005, and take the stress of the sample at 300% elongation in MPa according to ISO37:2005. The lower the tensile stress of the material, the more flexible and comfortable the article thus converted will be. In the present invention, the tensile stress of the film is preferably 13MPa or less, more preferably 10MPa or less.

[0064] Hysteresis loss: According to ISO 37:2005, a polyurethane membrane sample of standard shape and dimensions is taken, and according to DIN 53835-2:1981, the sample is stretched and contracted five times.

[0065] Relative stress loss b5 after repeated elongation = (stress at 300% elongation for the first time - stress at 300% elongation for the fifth time) / stress at 300% elongation for the first time * 100. b5 of the polyurethaneurea film of the present invention is preferably 20 or less, more preferably 15 or less.

[0066] Hysteresis loss factor H5=F150,5th unload / F150,5th load, H5 is the ratio of the unload force to the load force at the 5th cycle stretch-recovery at 150% strain. The H5 of the polyurethane membrane of the present invention is preferably 0.70 or more.

[0067] Elastic recovery rate RER%: According to ISO37:2005, take a film sample of standard shape and size of polyurethaneurea, stretch the sample 5 times, then, according to DIN53835-2:1981, test the length of the sample, and calculate the elastic recovery rate as follows: RER%=(1-(5th 300% extension recovery length-start length) / (300% extension length-start length))*100%

[0068] The %RER of the polyurethaneurea film of the present invention is preferably 90% or more.

[0069] The present invention will now be specifically illustrated with reference examples, but the present invention is not limited thereto. Further embodiments of the present invention can be seen from the claims, detailed description and examples.

[0070] Materials used: Lupranate (registered trademark) M: 4,4'-MDI manufactured by BASF DMAC: N,N-dimethylacetamide manufactured by BASF EDA: BASF 1,2-ethylenediamine DEA: N,N-diethylamine manufactured by BASF Irganox® 245: CAS36443-68-2 manufactured by BASF Tinuvin® 622: CAS70198-29-7 manufactured by BASF Deuterated DMF: CAS4472-41-7 from Merck. PolyTHF®: polytetrahydrofuran glycol manufactured by BASF

[0071] Preparation of copolymer glycols: Copolymer 1 is a copolymer glycol prepared according to the procedure of Example 1 of US Patent Application Publication No. 2012 / 0059143. 841 parts of PolyTHF® 650 (Mn 650 g / mol) were reacted with 166 parts of isophthalic acid by gradually increasing the temperature to 220° C. and reducing the pressure to 20 mbar under the catalysis of tetrabutyl orthotitanate at 20 ppm by weight relative to PolyTHF® 650. When the acid value reached 1 mg KOH / g or less, the temperature was cooled to 200° C., 20 ppm of 85 wt.% phosphoric acid was charged, and further cooled, resulting copolymer glycol 1 has an OH value of 34 mg KOH / g. Copolymers 2-4 were prepared according to the same procedure described above for Copolymer 1, and the number average molecular weights of the starting PolyTHF® and final copolymer glycol are summarized in Table 1, both tested according to ASTM-1899-2016.

[0072] [Table 1]

[0073] Example 1 100.00 parts by weight of Copolymer 1, 13.50 parts by weight of 4,4'-MDI, designated MDI-1 in Table 2, 2The NCO-capped prepolymer was then cooled to 40° C. and dissolved in 138.72 parts by weight of DMAC (referred to as DMAC-1 in Table 2). A solution of 1.34 parts by weight of EDA and 0.30 parts by weight of DEA as chain extenders in 105.94 parts by weight of DMAC (referred to as DMAC-2 in Table 2) was charged to the diluted prepolymer solution by high speed mixing to obtain a homogenous polyurethane solution.

[0074] An additive slurry of 0.5 wt% Irganox® 245, 0.2 wt% Tinuvin® 622, 0.2 wt% magnesium stearate, and 0.5 wt% titanium dioxide based on the weight of the solid polyurethane polymer was dosed into the polyurethaneurea solution. The viscosity of the resulting dope solution is 2000 poise at 30°C.

[0075] The doped solution was cast into a 0.24 mm thick film, and 15 mg of this film (cut into small pieces) was dissolved in deuterated DMF and examined by 1 H NMR.

[0076] The properties of the polyurethaneurea films thus obtained were tested according to the methods described above, and the results are summarized in Table 3.

[0077] Examples 2 to 6 A polyurethaneurea film was prepared in a manner similar to that of Example 1, except that the corresponding raw materials and their amounts were used as illustrated in Table 2. The properties of the polyurethaneurea film thus obtained were tested according to the above methods, and the measurement results are summarized in Table 3.

[0078] Comparative Example 1 100.00 parts by weight of Copolymer 2 was mixed with 14.48 parts by weight of 4,4'-MDI, designated MDI-1 in Table 2, to obtain an NCO-capped prepolymer with an NCO content of 1.80% by weight, which was then cooled and dissolved in 139.92 parts by weight of DMAC-1, during which the system was mechanically and N 2The percentage of NCO capped with amine due to side reactions was reduced dramatically to 1.25 wt%, where amine capped NCO refers to the NCO content remaining in the prepolymer at the time the amine solution was added for chain extension. A solution of 0.97 parts by weight of EDA as a chain extender and 0.21 parts by weight of DEA as a chain terminator in 105.86 parts by weight of DMAC-2 was then added with rapid stirring to obtain a polyurethaneurea solution.

[0079] The same additives as in Example 1 were added to obtain a polyurethaneurea solution having a viscosity of 1,400 poise at 30°C.

[0080] The polyurethaneurea film thus obtained exhibited a hard segment HS of 6.5% in Table 3.

[0081] The %RER dropped to 87% and bulging or lagging occurred in the converted fabric based on spinning, further knitting and repeated abrasion test results.

[0082] Comparative Example 2 100.00 parts by weight of Copolymer 2 was reacted with 14.95 parts by weight of 4,4'-MDI (referred to as MDI-1 in Table 2) to obtain an NCO-capped prepolymer having an NCO content of 1.93% by weight, followed by additional 4.67 parts by weight of 4,4'-MDI (referred to as MDI-2 in Table 2) being charged into the cooled prepolymer and stirred to obtain a homogeneous mixture, to which 146.20 parts by weight of DMAC (referred to as DMAC-1 in Table 2) was charged to obtain a prepolymer solution.

[0083] Next, a solution of 2.45 parts by weight of EDA as a chain extender and 0.54 parts by weight of DEA as a chain terminator in 114.34 parts by weight of DMAC (referred to as DMAC-2 in Table 2) was added, followed by the additives as in Example 1, to obtain a polyurethaneurea solution with a viscosity of 2300 poise at 30°C.

[0084] The viscosity of the polyurethaneurea solution increased to 8000 poise, which is outside the spinnable range, after standing at 50° C. for 72 hours. In the present invention, the dope viscosity needs to be adjusted to 2000-6000 poise during aging at 50° C. for 72 hours, otherwise the yarn breakage, binding and curling will be serious based on the results of the spinning test.

[0085] Besides the high and fast viscosity change during aging, the polyurethaneurea film exhibited a tensile stress of 13.6 MPa, as shown in Table 3.

[0086] Comparative Examples 3 and 4 The polyurethane urea elastomers were prepared in a similar manner to Example 1, except for the corresponding raw materials and their amounts as illustrated in Table 2, and in Comparative Example 3, PolyTHF® having Mn of 3000 was used instead of Copolymer 1, and in Comparative Example 4, PolyTHF® having Mn of 1850 was used instead of Copolymer 1.

[0087] In Comparative Example 3 and Comparative Example 4, the polyurethaneurea membranes show high recovery rates of 101% and 98%, respectively, but the high tensile stress and high energy loss of b5 in Table 3 cannot meet the requirements of downstream applications where comfort and fit are required.

[0088] Comparative Example 5 When 100.00 parts by weight of copolymer 2 was reacted with 15.20 parts by weight of 4,4'-MDI (referred to as MDI-1 in Table 2) to obtain an NCO capped prepolymer with an NCO content of 1.60% by weight instead of 2.00% by weight due to excessive NCO depletion by NCO side reactions or impurities such as water during the polymerization process, the prepolymer was subsequently dissolved in 140.80 parts by weight of DMAC-1, followed by rapid stirring of a solution of 1.24 parts by weight of EDA as a chain extender and 0.28 parts by weight of DEA as a chain terminator in 107.23 parts by weight of DMAC-2, the polymer solution showed severe gelation with the polyurethaneurea dope sticking to the stirring blade, and the viscosity was over 10,000 poise, far beyond the spinnable range of 2000-6000 poise, and no further measurements were made.

[0089] The polyurethaneurea films prepared according to the present invention exhibit a balanced combination of high elongation, low tensile stress, low hysteresis loss and good recovery force.

[0090] [Table 2]

[0091] [Table 3]

Claims

1. A polyurethane-urea fiber or film, comprising a hard segment content of 8.0 to 13.0% by weight, wherein the hard segment content is defined by the following formula: 【Number 1】 and the polyurethane-urea fiber or film is prepared via the use of a copolymer glycol, a polyurethane-urea fiber or film.

2. The hard segment content of the polyurethane-urea fiber or film is in the range of 8.0 to 12.5% by weight, the urethane moiety has a number average molecular weight Mn(urethane) of 5000 to 9000 g / mol, and the urea moiety has a number average molecular weight Mn(urea) of 500 to 900 g / mol. Preferably, the hard segment content of the polyurethane-urea fiber or film is in the range of 8.5 to 12.5% by weight, the urethane moiety has an Mn(urethane) of 5500 to 8500 g / mol, and the urea moiety has an Mn(urea) of 550 to 850 g / mol. The polyurethane-urea fiber or film according to Claim 1.

3. The copolymer glycol is prepared from at least one aromatic carboxylic acid and / or its anhydride and / or its ester and at least one polymer glycol. The polyurethane-urea fiber or film according to Claim 1.

4. The number average molecular weight (Mn) of the copolymer glycol is 500 to 5000 g / mol, preferably 1800 to 4000 g / mol, more preferably 2000 to 3500 g / mol. The polyurethane-urea fiber or film according to Claim 1.

5. The content of the aromatic carboxylic acid and / or its anhydride and / or its ester moiety in the copolymer glycol is 6.0 to 20.0% by weight. The polyurethane-urea fiber or film according to Claim 3.

6. The aromatic carboxylic acid and / or its anhydride and / or its ester is selected from isophthalic acid, dimethyl isophthalate, phthalic acid, terephthalic acid, and their anhydrides, preferably selected from isophthalic acid, dimethyl isophthalate, and mixtures thereof, more preferably selected from isophthalic acid. The polyurethane-urea fiber or film according to Claim 3.

7. The polymer glycol is selected from the group consisting of polytetrahydrofuran glycol, polyesterol, polyetherol, polycaprolactone and / or mixtures thereof, preferably, the polymer glycol contains polytetrahydrofuran glycol, more preferably, the polymer glycol is polytetrahydrofuran glycol, the polyurethane-urea fiber or film according to claim 1.

8. A process for producing the polyurethane-urea fiber or film according to any one of claims 1 to 7, a) reacting a copolymer glycol with at least one diisocyanate to obtain a urethane prepolymer containing isocyanate at both ends; b) adding a chain extender and optionally a chain terminator to the urethane prepolymer under an inert solvent to obtain a polyurethane-urea solution; c) dry-spinning the polyurethane-urea solution to obtain the polyurethane-urea fiber A process comprising.

9. The diisocyanate contains 4,4'-methylenediphenyl diisocyanate, preferably more than 60% of 4,4'-methylenediphenyl diisocyanate, more preferably more than 80% of 4,4'-methylenediphenyl diisocyanate, most preferably more than 95% of 4,4'-methylenediphenyl diisocyanate, the process according to claim 8.

10. The chain extender contains an aliphatic diamine having two hydrogen atoms reactive with isocyanate groups, preferably, the aliphatic diamine is selected from 1,2-ethylenediamine, 1,2-propylenediamine, 1,3-propylenediamine, 1,4-butanediamine, 1,5-pentanediamine, 1,4-cyclohexanediamine and mixtures thereof, more preferably, the aliphatic diamine is 1,2-ethylenediamine, the process according to claim 8.

11. The chain terminator is an alkyl alcohol and / or a dialkylamine, preferably, the chain terminator is selected from n-butanol, cyclohexanol, ethanolamine, diethanolamine, N,N-diethylamine, N,N-dibutylamine or mixtures thereof, the process according to claim 8.

12. Amines other than the chain extender and the chain terminator are added together with the chain extender, and preferably, the amines other than the chain extender and the chain terminator are diethylene triamine and / or diethanolamine, the process according to claim 8.

13. Use of the polyurethaneurea fiber according to any one of claims 1 to 7 for producing a fabric.

Images