A low processing temperature high resilience thermoplastic polyurethane elastomer

Abstract

The application provides a low-processing-temperature high-rebound thermoplastic polyurethane elastomer. By using a chain extender with a specific structure and a diol to react with diisocyanate, a multiple hydrogen bond structure is obtained, the introduction of the multiple hydrogen bond structure strengthens the rebound performance of the thermoplastic polyurethane elastomer, and the thermoplastic polyurethane elastomer has a lower initial flow temperature and is easy to process. The bonding adaptability of the elastic fabric for sports underwear, yoga clothes and the like is high, and the comprehensive performance is excellent.

Description

Technical Field

[0001] This invention belongs to the field of polyurethane elastomers, and specifically relates to a low-processing-temperature, high-resilience thermoplastic polyurethane elastomer. Background Technology

[0002] With the promotion and development of thermoplastic polyurethane elastomers, there is a high demand for materials with high resilience in the fields of seamless footwear and elastic clothing.

[0003] CN 100344666 C discloses a chain extender, 2,4-diamino-6-R-1,3,5-triazine, for synthesizing polyurethane elastomers, wherein R is an alkyl group. Thermoplastic polyurethane elastomers are synthesized by using this chain extender with polyols and isocyanates. The thermoplastic polyurethane elastomers have the characteristics of low tensile hysteresis deformation and high resilience. However, this chain extender increases the initial flow temperature of the thermoplastic polyurethane elastomer, which affects subsequent processing and use.

[0004] CN 110903805 A discloses a method for synthesizing thermoplastic polyurethane elastomers using modified hydroxyl-terminated hydrogenated polybutadiene polyols, diisocyanates, and small molecule chain extenders, followed by blending with SEBS / SEPS adhesive powder to prepare a polyurethane hot melt adhesive. This hot melt adhesive has advantages such as low polarity, high resilience, and low thermal activation temperature. However, the addition of SEBS / SEPS adhesive powder makes the product non-degradable, thus limiting its application.

[0005] Existing technologies have the problem of not being able to maintain high resilience at low processing temperatures, and cannot achieve both high resilience and low processing temperature in thermoplastic polyurethane elastomers. Summary of the Invention

[0006] One of the objectives of this invention is to provide a high-resilience thermoplastic polyurethane elastomer that has both low processing temperature and high resilience, thus achieving a thermoplastic polyurethane elastomer that combines high resilience and low processing temperature.

[0007] To achieve the above-mentioned objectives, the present invention provides the following technical solution:

[0008] A thermoplastic polyurethane elastomer, said elastomer being prepared from raw materials comprising the following parts by weight:

[0009] 60-80 wt% polyol, preferably 60-80 wt%.

[0010] Isocyanate 19-39 wt%, preferably 20-35 wt%.

[0011] Small molecule diols, 0-20 wt%, preferably 0-10 wt%.

[0012] Small molecule diamine, 1-21 wt%, preferably 2-20 wt%;

[0013] The small molecule diamine comprises the following structure:

[0014]

[0015] Where R1 and R2 independently represent O, S, and -NR. 1 One of them, R 1 It is a linear C1-C30 alkyl or a branched C1-C30 alkyl; R3 independently represents a linear C1-C30 alkyl. 30 Alkyl, branched C1-C 30 Alkyl, C6-C 10 Aryl, -OR 2 One of them, R 2 It is H, linear C1-C 30 Alkyl, branched C1-C 30 Alkyl group; n is an integer from 1 to 3; R4 and R5 independently represent C1-C2. 30 Alkyl groups, preferably C1-C 15 alkyl.

[0016] This invention obtains a multi-hydrogen bond structure by reacting a chain extender with a specific structure and a diol with a diisocyanate. The introduction of the multi-hydrogen bond structure enhances the resilience of the thermoplastic polyurethane elastomer, while also having a lower initial flow temperature, making it easy to process, and exhibiting high adhesion compatibility with elastic fabrics such as sports bras and yoga wear, resulting in excellent overall performance.

[0017] In one embodiment of the present invention, the polyol is a polyester polyol, preferably one or more of polyethylene adipate diol, polypropylene adipate diol, polybutylene adipate diol, polyhexane adipate diol, polyethylene adipate butylene adipate diol, polybutylene adipate butylene adipate diol, and polycaprolactone diol, more preferably one or more of polybutylene adipate diol, polyethylene adipate butylene adipate diol, polybutylene adipate butylene adipate diol, and polycaprolactone diol; preferably, the molecular weight of the polyol is 400-4500, more preferably 500-2500.

[0018] In one embodiment of the present invention, the diisocyanate is an aromatic diisocyanate and / or an aliphatic diisocyanate, preferably one or more of diphenylmethane diisocyanate, hexamethylene diisocyanate, toluene diisocyanate, isophorone diisocyanate, isophthalic diisocyanate, 1,5-naphthalene diisocyanate, and 4,4'-dicyclohexylmethane diisocyanate, more preferably one or more of hexamethylene diisocyanate, 4,4'-dicyclohexylmethane diisocyanate, diphenylmethane diisocyanate, and isophorone diisocyanate.

[0019] In one embodiment of the present invention, the small molecule diol is a C2-C12 small molecule diol, preferably one or more of ethylene glycol, 1,3-propanediol, 1,4-butanediol, methylpropanediol, diethylene glycol, 1,4-cyclohexanol, neopentyl glycol, 1,6-hexanediol, and 1,10-decanediol.

[0020] Another object of the present invention is to provide a method for preparing thermoplastic polyurethane elastomers.

[0021] A method for preparing thermoplastic polyurethane elastomer, wherein the method is a one-step method comprising the following steps: mixing a polyol component with a diisocyanate component, a small molecule diol and a small molecule diamine uniformly, and then preparing the elastomer by twin-screw reactive extrusion.

[0022] Alternatively, in one embodiment of the present invention, the method is a prepolymerization method, comprising the following steps: premixing a polyol component and a diisocyanate in a single-screw mixer to obtain a preliminary reaction mixture, and injecting the reaction mixture with a small molecule diol and a small molecule diamine into a twin-screw continuous reactive extruder for reaction.

[0023] Another object of the present invention is to provide a use of a thermoplastic polyurethane elastomer.

[0024] Use of a thermoplastic polyurethane elastomer, wherein the elastomer is the elastomer described above or an elastomer prepared by the method described above, wherein the elastomer is used to prepare a high-resilience thermoplastic polyurethane elastomer, preferably for preparing a high-resilience film, fine wire, or a web woven from the wire.

[0025] Another object of the present invention is to provide a thermoplastic polyurethane article.

[0026] A thermoplastic polyurethane article, wherein the article is made of the elastomer described above or an elastomer prepared by the method described above, wherein the article is a high-resilience thermoplastic polyurethane elastomer, preferably used for high-resilience films, fine wires, and wire meshes.

[0027] Compared with the prior art, the positive effects of the present invention are as follows:

[0028] (1) It has a low processing temperature, with an initial flow temperature between 110-132℃;

[0029] (2) It maintains excellent rebound performance, with a rebound rate of 300% between 75% and 100%. Detailed Implementation

[0030] The implementation method of the present invention is described in detail below, but the present invention is not limited thereto. Any modifications made to the technical solution of the present invention by those skilled in the art are within the scope of protection of the present invention. Unless otherwise specified, the raw materials used in the embodiments are commercially available.

[0031] Polybutylene adipate hexanediol (Mw=1500), Wanhua Chemical Group Co., Ltd., WHP-1546.

[0032] Polybutylene adipate hexanediol (Mw=2000), Wanhua Chemical Group Co., Ltd., WHP-2046.

[0033] Polybutylene adipate diol (Mw=1200), Wanhua Chemical Group Co., Ltd., WHP-124.

[0034] Polycaprolactone diol (Mw=500), Hunan Juren New Materials Co., Ltd., PCL-500

[0035] Polycaprolactone diol (Mw=800), Hunan Juren New Materials Co., Ltd., PCL-800

[0036] Polycaprolactone diol (Mw=400), Hunan Juren New Materials Co., Ltd., PCL-4500

[0037] Polyhexanediol adipate neopentyl glycol ester diol (Mw=4000), Wanhua Chemical Group Co., Ltd., WHP-4056.

[0038] Poly(ethylene glycol adipate) butylene glycol (Mw=1500), Wanhua Chemical Group Co., Ltd., WHP-1524.

[0039] 4,4'-Diphenylmethane diisocyanate: CAS101-68-8, Wanhua Chemical Group Co., Ltd.;

[0040] Hexamethylene diisocyanate: CAS 822-06-0, Wanhua Chemical Group Co., Ltd.;

[0041] Toluene diisocyanate: CAS 584-84-9, Wanhua Chemical Group Co., Ltd.;

[0042] 1,4-Butanediol: CAS110-63-4, Wanhua Chemical Group Co., Ltd.;

[0043] 1,6-Hexanediol: CAS 629-11-8, Shanghai Maclean Biochemical Technology Co., Ltd.;

[0044] 1,10-Decanediol: CAS112-47-0, Shanghai Maclean Biochemical Technology Co., Ltd.;

[0045] 1,12-Dodecanediol: 5675-51-4, Shanghai Maclean Biochemical Technology Co., Ltd.;

[0046] Diethyltoluenediamine (DETDA): Shanghai Maclean Biochemical Technology Co., Ltd.;

[0047] Biuret, N,N',2-Trimethyl: CAS 816-00-2, Hubei Yangxin Pharmaceutical Technology Co., Ltd.;

[0048] Urea, N,N'-dimethyl-N'-[(methylamino)(methyl)methyl]: CAS 780717-00-2, Shenzhen Aituo Chemical Co., Ltd.;

[0049] Methoxyamine: CAS 67-62-9, Aibisin (Shanghai) Biotechnology Co., Ltd.;

[0050] Propyl isocyanate: CAS110-78-1, Shanghai Aladdin Biochemical Technology Co., Ltd.;

[0051] N,N-Diethylhydrazine: CAS1615-80-1, Shaanxi Didu Pharmaceutical Chemical Co., Ltd.;

[0052] Cyclohexyl isocyanate: CAS 3173-53-3, Shanghai Aladdin Biochemical Technology Co., Ltd.;

[0053] 2-Methoxy-N,N'-dipropyl: CAS 5710-24-7, synthesized according to the following method: 1 mol of methoxyamine and 2 mol of propyl isocyanate were added in proportion to 1 L of frozen benzene as solvent and reacted at 10 °C for 1 h. Unreacted reactants and solvent benzene were removed by distillation, with the temperature gradually increased from 40 °C to 80 °C. The resulting product was analyzed by carbon NMR spectroscopy and found to have a purity of 99.6%.

[0054] 1,2-Hydroxyhydrazine, N,N'-dicyclohexyl-1,2-diethyl: CAS 40028-64-6, synthesized by the following method: 1 mol of N,N-diethylhydrazine and 2 mol of cyclohexyl isocyanate were added in proportion to 1 L of benzene at room temperature and reacted at 50 °C for 2 h. Unreacted reactants and benzene solvent were removed by vacuum distillation, with the temperature gradually increased from 40 °C to 80 °C. The resulting product was analyzed by carbon NMR spectroscopy and found to have a purity of 99.2%. Diethyltoluene diamine: CAS 68479-98-1, Shanghai Maclean Biochemical Technology Co., Ltd.

[0055] The initial flow temperature was tested using a Shimadzu CFT-500D rheometer, with the initial temperature set at 40℃ and the heating rate at 3℃ / min.

[0056] Example 1

[0057] 200 kg of thermoplastic polyurethane elastomer was prepared using a one-step method based on the following parts by weight of raw materials:

[0058] A high-resilience thermoplastic polyurethane elastomer was prepared by twin-screw reactive extrusion of 80 wt% polybutylene adipate hexanediol diol-1500, 19 wt% 4,4'-diphenylmethane diisocyanate, 1 wt% aminodicarbodiamine, and N,N',2-trimethylammonium (extruder temperatures: feed section 130℃, compression section 170℃, metering section 185℃, die 180℃). After pelleting under cooling water at 10℃, the elastomer was dried at 30℃ until the moisture content was less than 0.1%.

[0059] Example 2

[0060] 200 kg of thermoplastic polyurethane elastomer was prepared using a two-step method based on the following parts by weight of raw materials:

[0061] 80 wt% of polybutylene adipate hexanediol diol-1500 and 19 wt% 4,4'-diphenylmethane diisocyanate were premixed in a single-screw extruder. 1 wt% aminodicarbodiamine and N,N',2-trimethylamine were injected into a twin-screw continuous reactive extruder via a mass flow meter for reaction (feed section: 130°C, compression section: 180°C, metering section: 190°C, die section: 180°C) to obtain a high-resilience thermoplastic polyurethane elastomer. After pelleting under cooling water at 10°C, it was dried at 30°C until the moisture content was less than 0.1%.

[0062] Example 3

[0063] 200 kg of thermoplastic polyurethane elastomer was prepared using a one-step method based on the following parts by weight of raw materials:

[0064] A high-resilience thermoplastic polyurethane elastomer was prepared by twin-screw reactive extrusion of 72 wt% polybutylene adipate diol-1200, 19.5 wt% hexamethylene diisocyanate, 8.5 wt% aminodicarbodiamine, N,N',2-trimethylammonium (extruder temperature: feed section 120℃, compression section 160℃, metering section 175℃, die 170℃). After pelleting under cooling water at 10℃, the elastomer was dried at 30℃ until the moisture content was less than 0.1%.

[0065] Example 4

[0066] 200 kg of thermoplastic polyurethane elastomer was prepared using a one-step method based on the following parts by weight of raw materials:

[0067] A high-resilience thermoplastic polyurethane elastomer was prepared by reacting 75 wt% polybutylene adipate hexanediol diol-2000, 20 wt% 4,4'-dicyclohexylmethane diisocyanate, 2.5 wt% 1,4-butanediol, 2.5 wt% aminodicarbodiamine, N,N',2-trimethylamine, and 45 wt% ...

[0068] Example 5

[0069] 200 kg of thermoplastic polyurethane elastomer was prepared using a one-step method based on the following parts by weight of raw materials:

[0070] Polycaprolactone diol-500 (65 wt% of the total raw material mass) was mixed with 28.3 wt% toluene diisocyanate, 6.7 wt% urea, and N,N'-dimethyl-N'-[(methylamino)(methyl)methyl] and then subjected to twin-screw reactive extrusion (feed section: 130℃, compression section: 170℃, metering section: 180℃, die head: 175℃) to obtain a high-resilience thermoplastic polyurethane elastomer. After being pelletized in water at 10℃, it was dried at 30℃ until the moisture content was less than 0.1%.

[0071] Example 6

[0072] 200 kg of thermoplastic polyurethane elastomer was prepared using a two-step method based on the following parts by weight of raw materials:

[0073] Polycaprolactone diol-800 (60 wt% of the total raw material mass) and 4,4'-diphenylmethane diisocyanate (30 wt% of the total raw material mass) were premixed in a single-screw extruder. Then, 5 wt% 2-methoxy-N,N'-dipropyl and 5 wt% 1,6-hexanediol were injected into a twin-screw continuous reactive extruder via a mass flow meter for reaction (feed section: 130°C, compression section: 180°C, metering section: 190°C, die section: 180°C) to obtain a high-resilience thermoplastic polyurethane elastomer. After pelleting under cooling water at 10°C, it was dried at 30°C until the moisture content was less than 0.1%.

[0074] Example 7

[0075] 200 kg of thermoplastic polyurethane elastomer was prepared using a one-step method based on the following parts by weight of raw materials:

[0076] A high-resilience thermoplastic polyurethane elastomer was prepared by extruding 60 wt% polycaprolactone diol-4500, 19 wt% 4,4'-diphenylmethane diisocyanate, 1 wt% 1,2-hydrazine dicarboxyl, N,N'-dicyclohexyl-1,2-diethyl, and 20 wt% 1,12-dodecanediol through a twin-screw reactive extruder (feed section: 130°C, compression section: 170°C, metering section: 180°C, die: 175°C). After pelleting in water at 10°C, the elastomer was dried at 30°C until the moisture content was less than 0.1%.

[0077] Example 8

[0078] 200 kg of thermoplastic polyurethane elastomer was prepared using a one-step method based on the following parts by weight of raw materials:

[0079] A high-resilience thermoplastic polyurethane elastomer was prepared by extruding 60 wt% of polyhexamethylene adipate neopentyl glycol ester diol-4000, 19 wt% of 4,4'-dicyclohexylmethane diisocyanate, and 21 wt% of aminodicarbodiamine, N,N',2-trimethylammonium ether using a twin-screw reactive extruder (feed section: 130°C, compression section: 170°C, metering section: 180°C, die: 175°C). After pelletizing in water at 10°C, the elastomer was dried at 30°C until the moisture content was less than 0.1%.

[0080] Comparative Example 1

[0081] Compared with Example 3, the only difference is that aminodicarbondiamine, N,N',2-trimethyl is replaced with 1,10-decanediol.

[0082] A high-resilience thermoplastic polyurethane elastomer was prepared by twin-screw reactive extrusion of 72 wt% polybutylene adipate diol-1200, 19.5 wt% hexamethylene diisocyanate, and 8.5 wt% 1,10-decanediol (extruder temperature 160℃). The elastomer was pelletized under cooling water at 10℃ and dried at 30℃ until the moisture content was less than 0.1%.

[0083] Comparative Example 2

[0084] Compared with Example 6, the only difference is that 2-methoxy-N,N'-dipropyl is replaced with diethyltoluenediamine.

[0085] Polycaprolactone diol-800 (60 wt% of the total raw material mass) and 4,4'-diphenylmethane diisocyanate (30 wt% of the total raw material mass) were premixed in a single-screw extruder. Then, 5 wt% 1,6-hexanediol and 5 wt% diethyltoluenediamine were injected into a twin-screw continuous reactive extruder via a mass flow meter for reaction (feed section: 130°C, compression section: 180°C, metering section: 190°C, die section: 180°C) to obtain a high-resilience thermoplastic polyurethane elastomer. After pelleting under cooling water at 10°C, it was dried at 30°C until the moisture content was less than 0.1%.

[0086] The properties of thermoplastic polyurethane elastomers are tested as follows:

[0087] Hardness was tested according to ASTM D2240 standard; tensile strength was tested according to ASTM D412_16e1 standard, with a tensile speed of 100 mm / min.

[0088] The resilience was determined according to the standard HG / T3322-1981, "Determination of Permanent Deformation of Vulcanized Rubber at a Fixed Elongation". The resilience retention rate at 100% and 300% fixed elongation was tested respectively: a film with a width of 30mm × length of 127mm × thickness of 0.2mm was stretched to 100% and 300% and held for 5min and 1min respectively. Then the tension was removed and the film was allowed to recover at room temperature for 5min and 1min respectively. The recovery length of the product was then tested to confirm the fixed tensile deformation rate. The test result was the average value of 3 parallel samples.

[0089] The performance data of the TPU provided in the above embodiments and comparative examples are shown in Table 1.

[0090] As can be seen from the data in Table 1, the present invention introduces the small molecule diamine structure into the TPU structure, which adds multiple hydrogen bond structures to the TPU, improves the resilience of the film, and can obtain a film with good resilience by using either a one-step method or a prepolymerization method. At the same time, TPU has a low initial flow temperature and is easy to process.

[0091] Table 1

[0092]

[0093] Table 2

[0094] project Comparative Example 1 Comparative Example 2 polyols PBA-1200 PCL-800 Isocyanates HDI MDI Chain extender 1,10-Sebacic acid HDO + diethyltoluenediamine process One-step method Two-step method Hardness (Shore A) 82 62 Tensile strength (MPa) 39.6 22.8 100% deformation retention 57％ 82％ 300% deformation retention 50％ 75％ Initial flow temperature (°C) 106 146

[0095] The data above shows that Comparative Example 1 differs from Example 3 only in that N,N',2-trimethylamine is replaced with 1,10-decanediol. Although the flow point of Comparative Example 1 is lower than that of Example 3, its resilience is poor. Comparative Example 2 differs from Example 6 only in that 2-methoxy-N,N'-dipropyl is replaced with diethyltoluenediamine, which shows reduced resilience and a higher flow point.

[0096] It is readily understood that the above embodiments are merely illustrative examples for clear explanation and do not imply that the invention is limited thereto. Those skilled in the art will recognize that other variations or modifications can be made based on the above description. It is neither necessary nor possible to exhaustively list all possible implementations here. However, obvious variations or modifications derived therefrom are still within the scope of protection of this invention.

Claims

1. A thermoplastic polyurethane elastomer, characterized in that, The elastomer is prepared from raw materials comprising the following parts by weight: Polyols 60-80 wt%, Isocyanates 19-39 wt%, Small molecule diols 0-20wt%, Small molecule diamines, 1-21 wt%; The small molecule diamine comprises the following structure: Where R1 and R2 independently represent O, S, and -NR. 1 One of them, R 1 It is linear C1-C 30 Alkyl or branched C1-C 30 Alkyl; R3 independently represents linear C1-C 30 Alkyl, branched C1-C 30 Alkyl, C6-C 10 Aryl, -OR 2 One of them, R 2 It is linear C1-C 30 Alkyl, branched C1-C 30 Alkyl group; n is an integer from 1 to 3; R4 and R5 independently represent C1-C2. 30 alkyl.

2. The elastomer according to claim 1, characterized in that, The elastomer is prepared from raw materials comprising the following parts by weight: Polyols 60-75 wt%, Isocyanate 20-35 wt%, Small molecule diols 0-10 wt%, Small molecule diamines, 2-20 wt%; In the small molecule diamine, R4 and R5 independently represent C1-C2. 15 alkyl.

3. The elastomer according to claim 1 or 2, characterized in that, The polyol is a polyester polyol.

4. The elastomer according to claim 3, characterized in that, The polyol is one or more of the following: polyethylene adipate diol, propylene adipate diol, butyl adipate diol, hexane adipate diol, ethylene glycol butylene adipate diol, butylene adipate hexane adipate diol, and polycaprolactone diol. The molecular weight of the polyol is 400-4500.

5. The elastomer according to claim 4, characterized in that, The polyol is one or more of polybutylene adipate diol, polyethylene glycol butylene adipate diol, polybutylene adipate ethylene glycol butylene adipate diol, and polycaprolactone diol. The molecular weight of the polyol is 500-2500.

6. The elastomer according to claim 1 or 2, characterized in that, The isocyanate is an aromatic diisocyanate and / or an aliphatic diisocyanate.

7. The elastomer according to claim 6, characterized in that, The isocyanate is one or more selected from diphenylmethane diisocyanate, hexamethylene diisocyanate, toluene diisocyanate, isophorone diisocyanate, isophenyl dimethyl diisocyanate, 1,5-naphthalene diisocyanate, and 4,4'-dicyclohexylmethane diisocyanate.

8. The elastomer according to claim 7, characterized in that, The isocyanate is one or more of hexamethylene diisocyanate, 4,4'-dicyclohexylmethane diisocyanate, diphenylmethane diisocyanate, and isophorone diisocyanate.

9. The elastomer according to claim 1, characterized in that, The small molecule diol is a C2-C12 small molecule diol.

10. The elastomer according to claim 9, characterized in that, The small molecule diol is one or more selected from ethylene glycol, 1,3-propanediol, 1,4-butanediol, methylpropanediol, diethylene glycol, 1,4-cyclohexanol, neopentyl glycol, 1,6-hexanediol, and 1,10-decanediol.

11. A method for preparing a thermoplastic polyurethane elastomer, said method preparing the elastomer according to any one of claims 1-10, characterized in that, The method is a one-step method, which includes the following steps: mixing the polyol component with the isocyanate component, the small molecule diol and the small molecule diamine evenly, and then preparing it by twin-screw reactive extrusion; Alternatively, the method is a prepolymerization method, comprising the following steps: premixing polyol components and isocyanates in a single-screw mixer to obtain a preliminary reaction mixture, and injecting the reaction mixture with small molecule diols and small molecule diamines into a twin-screw continuous reactive extruder for reaction.

12. Use of a thermoplastic polyurethane elastomer, wherein the elastomer is any one of claims 1-10, or is an elastomer prepared by the method of claim 11, and the elastomer is used to prepare a high-resilience thermoplastic polyurethane elastomer.

13. The use according to claim 12, wherein the elastomer is used to prepare highly resilient films, fine threads, and webs woven from the threads.

14. A thermoplastic polyurethane article, wherein the article is prepared using the elastomer according to any one of claims 1-10, or the elastomer prepared by the method of claim 11, wherein the article is a high-resilience thermoplastic polyurethane elastomer.

15. The article of claim 14, wherein the article is a high-resilience film, a fine thread, or a mesh woven from the thread.

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