A reactive moisture-curing polyurethane hot melt adhesive, its preparation method and its application

Abstract

The present invention belongs to the field of polymer chemistry, and particularly relates to a reactive moisture-curing polyurethane hot melt adhesive with high moisture permeability. This hot melt adhesive is prepared by reacting an isocyanate component and an isocyanate-reactive component comprising the following parts by mass: The isocyanate component is: 20 to 35 parts by mass of isocyanate; The isocyanate-reactive component includes: at least one polyether polyol 35 to 45 parts by mass; at least one polyester polyol 10 to 25 parts by mass; at least one secondary amine group-containing polyether 5 to 10 parts by mass; chain extender 3 to 8 parts by mass. The reactive moisture-curing polyurethane hot melt adhesive of the present invention has excellent moisture permeability, high bonding strength, and excellent water washing resistance.

Description

Technical Field

[0001] The present invention belongs to the field of polymer chemistry, and particularly relates to a reactive moisture-curing polyurethane hot melt adhesive with high moisture permeability. Background Art

[0002] With the increasing improvement of human living standards, people's functional requirements for clothing are also getting higher and higher, such as warmth retention, fashion, antibacterial, waterproof, moisture permeability, windproof, etc. Fabrics with waterproof and moisture-permeable functions can reduce the stuffy feeling generated during exercise, so they are widely used in fields such as sportswear, mountaineering clothing, medical clothing, waterproof cloth, windbreaker, ski clothing, etc.

[0003] As a kind of environmentally friendly adhesive, reactive moisture-curing polyurethane hot melt adhesive (PUR) is currently widely used in various fabric composite fabrics. If general PUR products are used, the air permeability and moisture permeability of the composite fabric will be greatly reduced. Therefore, researchers are committed to developing PUR products with high moisture permeability performance.

[0004] Chinese patent document CN108290993 discloses a preparation method of a moisture-curing polyurethane hot melt adhesive: using polyethylene oxide ether, aromatic polyester, and crystalline polyester as polyol components. The disadvantage of this preparation method is that the introduced polyethylene oxide ether and aromatic polyester polyols are not conducive to the washability of textile fabrics.

[0005] Chinese patent document CN102167794 discloses a preparation method of a polyurethane prepolymer: more than 75% of the polyol is polybutylene glycol-ethylene glycol or polypropylene glycol. Although the prepolymer prepared by this method has excellent moisture permeability and washability, due to the high polyether content, it is not conducive to the final bonding performance of the product.

[0006] Chinese patent document CN1341133 discloses a high moisture permeability polyurethane hot melt adhesive with good hydrolysis resistance. The raw materials used are two kinds of polyether polyols, one is a polyethylene oxide-propylene oxide copolymerized diol with a low ethylene oxide content (less than 40%), and the other is a low molecular weight polyalkylene glycol. The polyester used is a crystalline polyester polyol. The hot melt adhesive prepared by this method has good washability, but due to the low ethylene oxide content, the moisture permeability is not good enough.

[0007] Chinese patent document CN101547991 discloses a moisture-curing polyurethane hot melt adhesive, a laminate using the same, and a moisture-permeable film. The raw material used is a high molecular weight polyethylene oxide ether with a number average molecular weight of 2000 - 25000. The hot melt adhesive prepared by this method has good moisture permeability, but the high molecular weight polyether has obvious crystallization, which affects the compatibility with other polyol components, and the bonding performance is average.

[0008] Chinese Patent CN109401282 discloses a highly flexible TPU film for clothing and its preparation method. Using a compound containing acidic groups and a small molecule aliphatic diamine as chain extenders at the same time, the primary amine forms a urea bond with the isocyanate, and a cross-linked structure is formed at the same time, making it difficult to achieve a soft handfeel.

[0009] Therefore, there is an urgent need to prepare a reactive moisture-curing polyurethane hot melt adhesive with excellent moisture permeability, bonding strength, washability and soft handfeel. Summary of the Invention

[0010] The present invention provides a reactive moisture-curing polyurethane hot melt adhesive PUR, which is prepared by reacting an isocyanate component and an isocyanate-reactive component including the following parts by mass:

[0011] The isocyanate component is:

[0012] 20-35 parts by mass of isocyanate, preferably 20-30 parts by mass, such as 20 parts by mass, 25 parts by mass or 30 parts by mass;

[0013] The isocyanate-reactive component includes:

[0014] At least one polyether polyol 35-45 parts by mass, preferably 40-45 parts by mass, such as 35 parts by mass, 40 parts by mass or 45 parts by mass;

[0015] At least one polyester polyol 10-25 parts by mass, preferably 15-25 parts by mass, such as 14 parts by mass, 17 parts by mass, 22 parts by mass or 25 parts by mass;

[0016] At least one secondary amino polyether 5-10 parts by mass, such as 5 parts by mass, 8 parts by mass, or 10 parts by mass;

[0017] Chain extender 3-8 parts by mass, such as 3 parts by mass, 5 parts by mass, or 8 parts by mass.

[0018] In a preferred example, the isocyanate-reactive component does not contain polyethylene oxide ether. Since the washability of polyethylene oxide ether is inferior to that of polyethylene oxide-propylene oxide copolymer ether and it has strong hygroscopicity, it is not conducive to the use stability of PUR products in an open state.

[0019] In a preferred example, the polyester polyol in the isocyanate-reactive component is a crystalline polyester polyol.

[0020] Preferably, in the above reactive moisture-curing polyurethane hot melt adhesive PUR, the chain extender is selected from small molecule diols containing carboxyl groups. Preferably, the small molecule diol containing carboxyl groups is dimethylolpropionic acid, dimethylolbutyric acid. More preferably, the small molecule diol containing carboxyl groups is dimethylolpropionic acid.

[0021] Preferably, in the above-mentioned reactive moisture-curing polyurethane hot melt adhesive PUR, the secondary amino polyether is secondary amino polyoxypropylene ether, and specifically, it can be selected from SD231, SD401 and SD2001 of Huntsman, and SD2001 is particularly preferred.

[0022] Preferably, in the above-mentioned reactive moisture-curing polyurethane hot melt adhesive PUR, the polyether polyol is selected from one or more of polyethylene oxide polyol, polypropylene oxide polyol, polyethylene oxide-propylene oxide copolymer and polytetrahydrofuran polyol; preferably, the polyether polyol is a polyethylene oxide-propylene oxide copolymer; more preferably, the content of ethylene oxide groups in the polyether polyol is 70-95 wt%, and the hydroxyl value is 25-120 mgKOH / g. The above-mentioned polyether polyol selected in the present invention has strong hydrophilicity due to its high ethylene oxide content, so it can significantly improve the moisture permeability of PUR. At the same time, it contains part of propylene oxide, which breaks the crystallinity of polyethylene oxide, making production convenient and improving the water wash resistance.

[0023] Preferably, in the above-mentioned reactive moisture-curing polyurethane hot melt adhesive PUR, the polyester polyol is a crystalline polyester polyol. Among them, the main chain of the crystalline polyester polyol does not contain side methyl groups, and the hydroxyl value is 20-300 mgKOH / g, preferably 30-120 mgKOH / g;

[0024] Preferably, the crystalline polyester polyol can be obtained by reacting a dibasic acid and a diol. The diol is selected from one or more of ethylene glycol, butanediol, hexanediol, octanediol and decanediol, and the dibasic acid is selected from one or more of adipic acid, suberic acid, sebacic acid and dodecanedioic acid. It can also be obtained by ring-opening of lactones, such as caprolactone, valerolactone, etc. Preferably, the initiator of the polycaprolactone is dimethylolpropionic acid.

[0025] The isocyanate component refers to compounds having isocyanate groups, and examples thereof include, but are not limited to, toluene diisocyanate (TDI), diphenylmethane diisocyanate (MDI), 1,5-naphthalene diisocyanate (NDI), hexamethylene diisocyanate (HDI), methylcyclohexyl diisocyanate, 4,4'-dicyclohexylmethane diisocyanate, isophorone diisocyanate (IPDI), p-phenylene diisocyanate (PPDI), p-xylylene diisocyanate (XDI), tetramethylxylylene diisocyanate (TMXDI), 1,4-cyclohexane diisocyanate (CHDI), cyclohexane dimethylene diisocyanate (HXDI), trimethyl-1,6-hexamethylene diisocyanate (TMHDI), norbornane diisocyanate (NBDI), dimethylbiphenyl diisocyanate (TODI), methylcyclohexyl diisocyanate (HTDI), etc., as well as polymers and modified products of such compounds. Such isocyanate compounds can be used alone or in combination (above); preferably, the isocyanate component is preferably diphenylmethane diisocyanate.

[0026] Preferably, in the above reactive moisture-curing polyurethane hot melt adhesive PUR, the molar ratio of the isocyanate group in the isocyanate component to the active hydrogen in the isocyanate-reactive component is 1.1 to 3.0:1, preferably 1.5 to 1.8:1, such as 1.5:1, 1.6:1 or 1.8:1; the active hydrogen is derived from: the hydroxyl group of polyether polyol; the hydroxyl group of polyester polyol; the amino group of secondary amine polyether; the hydroxyl group of chain extender dimethylolpropionic acid.

[0027] The reactive moisture-curing polyurethane hot melt adhesive PUR according to the present invention can be added with one or more auxiliaries known in the prior art as needed.

[0028] The auxiliaries include, but are not limited to, catalysts, stabilizers, chain extenders, fillers, dyes, defoamers, thixotropic aids, plasticizers, coupling agents, adhesion promoters, leveling agents, etc. known in the art.

[0029] Preferably, in the above reactive moisture-curing polyurethane hot melt adhesive PUR, the reactive moisture-curing polyurethane hot melt adhesive further comprises at least one of the following auxiliaries in parts by mass:

[0030]

[0031] The catalyst refers to a class of compounds commonly used in the art for catalyzing the reaction of isocyanate groups with active hydrogen atoms, and examples thereof include, but are not limited to, stannous octoate, dibutyltin dilaurate, 2,2-dimorpholinodiethyl ether, triethylenediamine, triethanolamine, etc.

[0032] The stabilizer is one or a combination of an antioxidant and a light stabilizer. The antioxidant is one or more of BHT, CHINOX1010, CHINOX 1076, CHINOX 1098, CHINOX 1024, CHINOX 245, CHINOX 1035, CHINOX 1135; the light stabilizer is one or more of CHISORB 320, UV-1, UV-P, UV-292, UV-329.

[0033] Coupling agents are well-known in the art of the present invention and include, but are not limited to, aminopropyltriethoxysilane, glycidoxypropyltrimethoxysilane, methacryloxypropyltrimethoxysilane, etc.

[0034] The defoamer refers to polymers such as polyolefins and polysiloxanes commonly used in the art to improve the performance of products.

[0035] In a specific embodiment, the preparation method of the reactive moisture-curing polyurethane hot melt adhesive PUR includes the following steps:

[0036] (1) Take the raw material polyether polyol and polyester polyol into a four-necked flask, and then evacuate to dehydrate so that the moisture content does not exceed 0.03 wt%; (2) Take the measured isocyanate and add it to the four-necked flask, control the temperature in the reaction flask at 60-80 °C, and react for 2-4 h; (3) Then add the measured antioxidant and catalyst under stirring; (4) Continue to add the measured secondary amino group polyol, control the reaction temperature at 60-80 °C, and stir and react for 0.5-2 h; (5) Raise the reaction temperature to 110-120 °C, then add the measured dimethylolpropionic acid, control the reaction temperature at 110-120 °C, and stir and react for 1-3 h; (6) Then add the measured coupling agent, control the reaction temperature at 110-120 °C, and stir and react for 0.5-2 h; (7) When the NCO value in the reaction system reaches the theoretical NCO value ±0.2 wt%, stir evenly, discharge, and package in a sealed manner to obtain the corresponding PUR product.

[0037] In the step (1), the temperature for vacuum dehydration is 100-120 °C and the time is 1-4 h.

[0038] The present invention also provides the application of the reactive moisture-curing polyurethane hot melt adhesive PUR in the adhesion of textile fabrics. The textile fabrics include, but are not limited to, polyester fabrics, nylon fabrics, blended fabrics, TPU films, PU films, and PTFE films. The fabrics can be of no waterproof grade or of high waterproof grade.

[0039] It should be noted that the various technical effects described in the present invention are all achieved by the combined action and mutual cooperation of the various components.

[0040] The technical solution of the present invention has the following advantages:

[0041] (1) The present invention uses dimethylolpropionic acid as a chain extender. The introduction of carboxyl groups can, on the one hand, improve the moisture permeability of the product, and on the other hand, inhibit the side effects in the urethane reaction, improving the production and use performance of the product. Due to its own water solubility, dimethylolpropionic acid causes a certain degree of reduction in the washability of the fabric composite product. In the present invention, by using dimethylolpropionic acid in combination with secondary amine polyether, the bond energy between molecules and with the fabric substrate is enhanced, and a polyurethane hot melt adhesive product with excellent washability can be prepared.

[0042] (2) In the present invention, the raw materials cooperate with each other, and the prepared reactive moisture-curing polyurethane hot melt adhesive not only has excellent moisture permeability and peel strength, but also has excellent washability. Specific Embodiments

[0043] The present invention will be further described below in conjunction with embodiments, but is not intended to limit the present invention.

[0044] The raw materials and sources of the examples and comparative examples are as follows:

[0045] Isocyanate: Wannate MDI-100, diphenylmethane diisocyanate, Wanhua Chemical Group Co., Ltd.;

[0046] Polyether polyol 2A: Polyethylene oxide-propylene oxide copolymer, diol, with an ethylene oxide content of 75 wt% and a hydroxyl value of 30 mg KOH / g;

[0047] Polyether polyol 2B: Polyethylene glycol, with an ethylene oxide content of 100 wt% and a hydroxyl value of 56 mg KOH / g;

[0048] Crystalline polyester 3A: Obtained by reacting dodecanedioic acid and hexanediol, with a hydroxyl value of 32 mg KOH / g;

[0049] Crystalline polyester 3B: Obtained by reacting adipic acid and hexanediol, with a hydroxyl value of 112 mg KOH / g;

[0050] Crystalline polyester 3C: Obtained by reacting adipic acid and hexanediol, with a hydroxyl value of 14 mg KOH / g;

[0051] Crystalline polyester 3D: Obtained by reacting adipic acid and hexanediol, with a hydroxyl value of 32 mg KOH / g;

[0052] Dimethylolpropionic acid, chemically pure, GEO Specialties;

[0053] SD2001: Secondary amine polyether, supplier Huntman;

[0054] Antioxidant 1010: Pentaerythritol tetra[β-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate], Double Bond Chemical Industry;

[0055] Catalyst: DMDEE, 2,2-Dimorpholinodiethyl ether;

[0056] Coupling agent: KH560, γ-Glycidoxypropyltrimethoxysilane.

[0057] The raw material ratios of Examples 1-4 and Comparative Examples 1-2 are shown in Table 1.

[0058] Table 1 Raw material ratios of examples and comparative examples

[0059] Raw materials, parts by mass Example 1 Example 2 Example 3 Example 4 Comparative Example 1 Comparative Example 2 Isocyanate 20 25 31 35 21 21 Polyether polyol 2A 42 40 0 0 42 42 Polyether polyol 2B 0 0 45 35 0 0 Crystalline polyester 3A 5 4 0 0 0 0 Crystalline polyester 3B 0 0 0 0 37 0 Crystalline polyester 3C 20 0 0 0 0 32 Crystalline polyester 3D 0 18 14 17 0 0 SD2001 10 8 5 5 0 0 Dimethylolpropionic acid 3 5 6 8 0 5 Antioxidant 1010 0.01 0.01 0.01 0.01 0.01 0.01 Catalyst DMDEE 0.05 0.05 0.05 0.05 0.05 0.05 Coupling agent KH560 0.5 0.5 0.5 0.5 0.5 0.5 NCO, % 3 3.4 3.9 4.7 2.9 2.5 R 1.8 1.7 1.6 1.7 1.7 1.6

[0060] The preparation method of the reactive moisture-curing polyurethane hot melt adhesive PUR of Examples 1-4 and Comparative Examples 1-2 includes the following steps: (1) According to the raw material ratios in Table 1, take the measured polyether polyols 2A-2B and polyester polyols 3A-3D and add them to a four-necked flask, and then dehydrate under vacuum at 120°C for 2 hours to make the moisture content not exceed 0.03 wt%; (2) Then take the measured isocyanate and add it to the four-necked flask, control the temperature in the reaction flask at 80°C, and react for 3 h; (3) Then add the measured antioxidant and catalyst under stirring; (4) Continue to add the measured secondary amino group polyol, control the reaction temperature at 80°C, and stir and react for 1 h; (5) Raise the reaction temperature to 120°C, then add the measured dimethylolpropionic acid, control the reaction temperature at 120°C, and stir and react for 1 h; (5) Then add the measured coupling agent KH560, control the reaction temperature at 120°C, and stir and react for 0.5 h; (6) When the NCO value in the reaction system reaches the theoretical NCO value ±0.2 wt%, stir evenly, discharge, and package tightly to obtain the corresponding PUR product.

[0061] Use the raw material ratios of Examples 1-4 and Comparative Examples 1-2 to prepare reactive moisture-curing polyurethane hot melt adhesive PUR samples to bond the fabric and TPU film. The fabric is 75D polyester pongee, and the TPU film is a medium-transparency film. After completion of the lamination, cure at a temperature of 23°C and a humidity of 50% for 24 h, and then test each property according to the following method.

[0062] Peeling force test method: Use an electric iron to bond the hot melt adhesive strip to the cured fabric-film product, and then cut it along the hot melt adhesive strip to a standard of 2.5 cm, and use a tensile machine to test the peeling force.

[0063] Moisture permeability test method: According to the ASTM E96BW standard, the inverted cup method is used. The prepared composite cloth film samples of a certain area are respectively fixed to the sample cups filled with pure water, and then the sample cups are inverted on the internal turntable of the moisture permeability instrument. Record the mass difference within a certain time difference, and calculate the moisture permeability (g / m 2 ﹒24h) of the sample through the secondary mass difference.

[0064] Washing resistance test method: The prepared composite cloth film samples are respectively washed in a washing machine. The washing conditions are 40°C and each washing lasts for 1 hour; the total number of washings is 20 times.

[0065] The specific test results are shown in Table 2.

[0066] Table 2 Test results of Examples 1-4 and Comparative Examples 1-2

[0067] Performance test Example 1 Example 2 Example 3 Example 4 Comparative Example 1 Comparative Example 2 Viscosity, cps (90 °C) 3200 3600 4200 3300 3000 7000 Peeling force, N / 2.5 cm 15 16 18 18 8 6 Moisture permeability (g / m2·24h) 5700 5800 6000 5500 5000 5400 Washed 20 times No delamination No delamination No delamination No delamination No delamination Delamination

[0068] As can be seen from Table 2, compared with Comparative Examples 1-2, the PUR prepared in Examples 1-4 has higher peeling force, better moisture permeability and excellent washing resistance after being used for fabric composite. In Comparative Example 1, no dimethylolpropionic acid and secondary amino polyether are added, and both the moisture permeability and peeling force are inferior to those in Example 1. In Comparative Example 2, no secondary amino polyether is added, and the peeling force and washing resistance are inferior to those in Example 1.

[0069] Obviously, the above examples are only for clear illustration and not limitations on the implementation manners. For those of ordinary skill in the art, other different forms of changes or modifications can be made based on the above description. It is not necessary and impossible to enumerate all the implementation manners here. And the obvious changes or modifications derived therefrom are still within the protection scope of the present invention.

Claims

1. A reactive moisture-curing polyurethane hot melt adhesive is prepared by reacting an isocyanate component and an isocyanate-reactive component comprising the following parts by mass: The isocyanate component is: 20 - 35 parts by mass of isocyanate; The isocyanate-reactive component includes: 35 - 45 parts by mass of at least one polyether polyol; 10 - 25 parts by mass of at least one polyester polyol; 5 - 10 parts by mass of at least one secondary amino polyether; 3 - 8 parts by mass of a chain extender, and the chain extender in the isocyanate-reactive component is dimethylolpropionic acid.

2. The reactive moisture-curing polyurethane hot melt adhesive according to claim 1, wherein The isocyanate component is: 20 - 30 parts by mass of isocyanate; The isocyanate-reactive component includes: 40 - 45 parts by mass of at least one polyether polyol; 15 - 25 parts by mass of at least one polyester polyol; 5 - 10 parts by mass of at least one secondary amino polyether; 3 - 8 parts by mass of a chain extender, and the chain extender in the isocyanate-reactive component is dimethylolpropionic acid.

3. The reactive moisture-curing polyurethane hot melt adhesive according to claim 1, characterized in that, The secondary amino polyether in the isocyanate-reactive component is secondary amino polyoxypropylene ether.

4. The reactive moisture-curing polyurethane hot melt adhesive according to any one of claims 1-3, characterized in that, The polyether polyol is selected from one or more of polyethylene oxide polyol, polypropylene oxide polyol, polyethylene oxide - propylene oxide copolymer, and polytetrahydrofuran polyol; and / or, the polyester polyol is a crystalline polyester polyol, and the main chain of the crystalline polyester polyol does not contain side methyl groups and has a hydroxyl value of 20 - 300 mgKOH / g.

5. The reactive moisture-curing polyurethane hot melt adhesive according to claim 4, wherein, The main chain of the crystalline polyester polyol does not contain side methyl groups and has a hydroxyl value of 30 - 120 mgKOH / g.

6. The reactive moisture-curing polyurethane hot melt adhesive according to any one of claims 1-3, characterized in that, The isocyanate component is selected from compounds having isocyanate groups.

7. The reactive moisture-curing polyurethane hot melt adhesive according to claim 6, characterized in that, The isocyanate component is selected from toluene diisocyanate (TDI), diphenylmethane diisocyanate (MDI), 1,5 - naphthalene diisocyanate (NDI), hexamethylene diisocyanate (HDI), methylcyclohexyl diisocyanate, 4,4'-dicyclohexylmethane diisocyanate, isophorone diisocyanate (IPDI), p-phenylene diisocyanate (PPDI), p-phenylenedimethylene diisocyanate (XDI), tetramethylenedimethylene diisocyanate (TMXDI), 1,4 - cyclohexane diisocyanate (CHDI), cyclohexanedimethylene diisocyanate (HXDI), trimethyl - 1,6 - hexamethylene diisocyanate (TMHDI), norbornane diisocyanate (NBDI), dimethylbiphenyl diisocyanate (TODI), methylcyclohexyl diisocyanate (HTDI), and polymers and modified products of such compounds.

8. The reactive moisture-curing polyurethane hot melt adhesive according to any one of claims 1-3, characterized in that, The molar ratio of the isocyanate group in the isocyanate component to the active hydrogen in the isocyanate-reactive component is 1.1 - 3.0:

1.

9. The reactive moisture-curing polyurethane hot melt adhesive according to claim 8, characterized in that, The molar ratio of the isocyanate group in the isocyanate component to the active hydrogen in the isocyanate-reactive component is 1.5 - 1.8:

1.

10. The reactive moisture-curing polyurethane hot melt adhesive according to any one of claims 1 to 3, characterized in that, The reactive moisture-curing polyurethane hot melt adhesive PUR further contains one or more additives, and the additives include but are not limited to catalysts, stabilizers, chain extenders, fillers, dyes, defoamers, thixotropic aids, plasticizers, coupling agents, adhesion promoters, and leveling agents.

11. The reactive moisture-curing polyurethane hot melt adhesive according to claim 10, wherein, The reactive moisture-curing polyurethane hot melt adhesive further comprises at least one of the following auxiliaries in parts by mass: 0 to 0.5 part by mass of a stabilizer; 0 to 0.5 part by mass of an antifoaming agent; 0 to 0.5 part by mass of a catalyst; 0 to 5 parts by mass of a coupling agent.

12. The reactive moisture-curing polyurethane hot melt adhesive according to claim 10, characterized in that, The catalyst is selected from stannous octoate, dibutyltin dilaurate, 2,2-dimorpholinodiethylether, triethylenediamine, and triethanolamine; and / or, the stabilizer is one or a combination of two of an antioxidant and a light stabilizer. The antioxidant is one or more of BHT, CHINOX 1010, CHINOX 1076, CHINOX 1098, CHINOX 1024, CHINOX 245, CHINOX 1035, and CHINOX 1135; the light stabilizer is one or more of CHISORB 320, UV-1, UV-P, UV-292, and UV-329; and / or, the coupling agent is selected from aminopropyltriethoxysilane, glycidoxypropyltrimethoxysilane, and methacryloxypropyltrimethoxysilane; and / or, the antifoaming agent is selected from polyolefins and polymers of polysiloxanes.

13. Application of the reactive moisture-curing polyurethane hot melt adhesive according to any one of claims 1-12 in the adhesion of textile fabrics, where the textile fabrics include but are not limited to polyester fabrics, nylon fabrics, blended fabrics, TPU films, PU films, and PTFE films.

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