阅读说明：本技术 一种抗湿滑低滚阻热塑性聚氨酯弹性体及制备方法 (Anti-slippery low-rolling-resistance thermoplastic polyurethane elastomer and preparation method thereof ) 是由 张立群 胡仕凯 寿韬 赵秀英 于 2019-09-30 设计创作，主要内容包括：本发明提供了一种抗湿滑低滚阻热塑性聚氨酯弹性体,以包含大分子二元醇的链段为软段,以包含二甲基联苯二异氰酸酯和小分子二元醇和/或小分子二元胺的链段为硬段,通过预聚法制备出一系列不同分子量的热塑性聚氨酯弹性体,该热塑性聚氨酯弹性体具有优异的抗湿滑、低滚动阻力、低生热等性能,能完美解决轮胎工业中魔鬼三角问题；而且可以直接加工成制品,降低加工能耗,同时边角余料和废料可回收利用,是解决传统橡胶的高能耗、高物耗、高污染的重要途径。(The invention provides a wet-skid-resistant low-rolling-resistance thermoplastic polyurethane elastomer, which takes a chain segment containing macromolecular dihydric alcohol as a soft segment and a chain segment containing dimethyl diphenyl diisocyanate and micromolecular dihydric alcohol and/or micromolecular diamine as a hard segment, and prepares a series of thermoplastic polyurethane elastomers with different molecular weights by a prepolymerization method, wherein the thermoplastic polyurethane elastomer has excellent performances of wet skid resistance, low rolling resistance, low heat generation and the like, and can perfectly solve the magic triangle problem in the tire industry; and the rubber can be directly processed into products, so that the processing energy consumption is reduced, and meanwhile, leftover materials and waste materials can be recycled, so that the rubber is an important way for solving the problems of high energy consumption, high material consumption and high pollution of the traditional rubber.)

1. The thermoplastic polyurethane elastomer takes a chain segment containing macromolecular dihydric alcohol as a soft segment and takes a chain segment containing dimethyl diphenyl diisocyanate and micromolecular dihydric alcohol and/or micromolecular diamine as a hard segment.

2. The thermoplastic polyurethane elastomer according to claim 1, characterized in that:

the molecular weight of the macromolecular dihydric alcohol is 650-4000, preferably 1000-3000; and/or the presence of a gas in the gas,

the molecular weight of the micromolecular dihydric alcohol or the micromolecular diamine is 62-500, preferably 90-380; and/or the presence of a gas in the gas,

the molar ratio of the macromolecular dihydric alcohol, the dimethyl biphenyl diisocyanate to the micromolecular dihydric alcohol and/or micromolecular diamine is 1: (1-5): (0.3 to 4), preferably 1: (1.5-4): (0.5 to 3).

3. The thermoplastic polyurethane elastomer according to claim 1 or2, characterized in that:

the macromolecular dihydric alcohol is polyglycol; the polyglycol is preferably at least one of polyester diol, polycaprolactone diol, polycarbonate diol, polycaprolactone carbonate copolyol, polybutadiene diol and polylactic caprolactone copolyol; and/or the presence of a gas in the gas,

the micromolecular dihydric alcohol is at least one selected from ethylene glycol, diethylene glycol, 1, 3-propylene glycol, 1, 4-butanediol, 1, 6-hexanediol, hydroquinone dihydroxyethyl ether, resorcinol dihydroxyethyl ether and bisphenol A dihydroxyethyl ether; and/or the presence of a gas in the gas,

the small-molecular diamine is selected from at least one of 3, 3' -dichloro-4, 4 ' -diphenylmethane diamine, 3, 5-dimethylthiotoluene diamine, 3, 5-diethyltoluene diamine, 4 ' -methylene bis (3-2, 6-diethylaniline), 4-methylene bis (2-isopropyl-6-methyl) aniline and 4, 4-methylene bis (2-ethylaniline).

4. The thermoplastic polyurethane elastomer according to any one of claims 1 to 3, which has a molecular weight of 40000 to 100000, a molecular weight distribution of 1.2 to 1.9, a glass transition temperature of-25 to-15 ℃, a hardness in the range of 60 Shore A to 95 Shore A, a loss factor tan δ max of 0.38 to 0.81, a loss factor at 0 ℃ of 0.31 to 0.71, and a loss factor at 60 ℃ of 0.02 to 0.05.

5. A method for preparing the wet skid resistant low rolling resistance thermoplastic polyurethane elastomer according to any one of claims 1 to 4, characterized by comprising the steps of:

1) carrying out prepolymerization reaction on macromolecular diol and dimethyl biphenyl diisocyanate to obtain an isocyanate-terminated prepolymer;

2) adding a chain extender into the prepolymer obtained in the step 1) to carry out chain extension reaction to obtain the wet-skid-resistant low-rolling-resistance thermoplastic polyurethane elastomer.

6. The method of claim 5, wherein:

the macrodiol is polyglycol, the molecular weight of the polyglycol is 650-4000, preferably 1000-2000, and the polyglycol is further selected from at least one of polyester diol, polycaprolactone diol, polycarbonate diol, polycaprolactone carbonate copolyol, polybutadiene diol and polylactic acid caprolactone copolyol; and/or the presence of a gas in the gas,

the chain extender is selected from micromolecular dihydric alcohol and/or micromolecular diamine, wherein the micromolecular dihydric alcohol is selected from at least one of ethylene glycol, diethylene glycol, 1, 3-propylene glycol, 1, 4-butanediol, 1, 6-hexanediol, hydroquinone dihydroxyethyl ether, resorcinol dihydroxyethyl ether and bisphenol A dihydroxyethyl ether; the small molecule diamine is at least one selected from 3,3 '-dichloro-4, 4' -diphenylmethanediamine, 3, 5-dimethylthiotoluenediamine, 3, 5-diethyltoluenediamine, 4, -methylenebis (3-2, 6-diethylaniline), 4, -methylenebis (2-isopropyl-6-methyl) aniline, 4, -methylenebis (2-ethylaniline).

7. The method of claim 5, wherein:

the molar ratio of the macromolecular diol to the dimethyl biphenyl diisocyanate to the chain extender is 1: (1-5): (0.3 to 4), preferably 1: (1.5-4): (0.5 to 3).

8. The method of claim 5, wherein:

in the step 1), before the macromolecular dihydric alcohol reacts with the dimethyl biphenyl diisocyanate, the macromolecular dihydric alcohol is subjected to water removal treatment; and/or the presence of a gas in the gas,

in the step 1), 0.005-0.1 wt% of catalyst, 0.1-2 wt% of antioxidant and 0.1-2 wt% of anti-ultraviolet agent are added according to the mass of macromolecular diol, micromolecular diol and dimethyl biphenyl diisocyanate; and/or the presence of a gas in the gas,

the thermoplastic polyurethane elastomer obtained in the step 2) is also subjected to curing treatment.

9. The method of claim 8, wherein:

the catalyst is at least one of an organic tin catalyst, an organic zinc catalyst and an organic bismuth catalyst, and preferably at least one of stannous octoate, dibutyltin diacetate, dibutyltin dilaurate, dibutyltin didodecyl sulfide, zinc isooctoate and bismuth isooctanoate.

10. The method of claim 5, wherein:

the prepolymerization temperature is 60-100 ℃, and the prepolymerization time is 2-4 h; and/or the presence of a gas in the gas,

the chain extension reaction temperature is 70-100 ℃, and the chain extension reaction time is 2-40 min.

Technical Field

The invention relates to the field of preparation of polyurethane elastomer materials, in particular to a wet-skid-resistant low-rolling-resistance thermoplastic polyurethane elastomer and a preparation method thereof.

Background

The thermoplastic polyurethane elastomer is a block copolymer which is mainly composed of isocyanate, macromolecular polyol and micromolecular polyol chain extender. The traditional rubber processing industry has two problems of high energy consumption and difficult recovery, the thermoplastic elasticity has the elasticity of rubber when in use, meanwhile, the thermoplastic plastic can be directly processed and molded into products without mixing and vulcanization like rubber, the processing energy consumption is obviously reduced, and meanwhile, leftover bits and pieces and waste materials can be recycled, so that the rubber processing industry is an important way for solving the problems of high energy consumption, high material consumption and high pollution of the traditional rubber. The thermoplastic polyurethane elastomer has wide hardness range, the hardness can be as low as a low-modulus material below Shore A10, and as high as Shore D90, and the hardness range almost comprises the hardness range of the used high polymer.

The thermoplastic polyurethane elastomer is prepared by adopting Toluene Diisocyanate (TDI) and diphenylmethane diisocyanate (MDI) by persons skilled in the art, and due to the asymmetry of the structures of the toluene diisocyanate and the diphenylmethane diisocyanate, the storage time of the prepolymer is short, the phase separation degree of the synthesized thermoplastic polyurethane is not high, the dynamic performance is not good, and the heat generation is high.

Chinese patent CN107760015A discloses that dimethyl diphenyl diisocyanate (TODI) is used as a diisocyanate and 1, 5-Naphthalene Diisocyanate (NDI) is used together to synthesize a polyurethane composite material dedicated for circuit boards, and the obtained polyurethane composite material cannot be processed repeatedly. Chinese patent CN105237729A discloses that TODI synthesizes a corrosion resistant polyurethane material, and the obtained polyurethane is not a thermoplastic polyurethane material and can not be processed repeatedly. China patent CN102181037A Shielen and the like disclose that TODI synthesizes thermoplastic polyurethane with hardness of Shore A86-96, but the thermoplastic polyurethane is applied to tires and does not solve the magic triangle problem of the tires, namely the balance among wear resistance, wet skid resistance and rolling resistance.

Disclosure of Invention

In order to solve the technical problems, the invention combines the characteristics of symmetrical structure, excellent dynamic performance and small endogenous heat of the dimethylbiphenyl diisocyanate (TODI) to prepare a series of wet-skid-resistant low-rolling-resistance thermoplastic polyurethane elastomers based on the TODI by a prepolymer method.

One of the purposes of the invention is to provide a wet-skid-resistant low-rolling-resistance thermoplastic polyurethane elastomer, wherein a chain segment containing macrodiol is used as a soft segment, and a chain segment containing dimethylbiphenyl diisocyanate and micromolecular diol and/or micromolecular diamine is used as a hard segment.

Wherein the molecular weight of the macrodiol is 650-4000, preferably 1000-3000; the macrodiol is polyglycol, preferably at least one of polyester diol, polycaprolactone diol, polycarbonate diol, polycaprolactone carbonate copolyol, polybutadiene diol, and polylactic caprolactone copolyol;

the molecular weight of the small molecular diol or the small molecular diamine is 62-500, preferably 90-380, wherein the small molecular diol is at least one selected from ethylene glycol, diethylene glycol, 1, 3-propylene glycol, 1, 4-Butanediol (BDO), 1, 6-Hexanediol (HDO), hydroquinone dihydroxyethyl ether (HQEE), resorcinol dihydroxyethyl ether (HER) and bisphenol A dihydroxyethyl ether; the small molecule diamine is at least one selected from 3, 3' -dichloro-4, 4 ' -diphenylmethane diamine (MOCA), 3, 5-dimethylthiotoluene diamine (DMTDA), 3, 5-diethyltoluene diamine, 4 ' -methylenebis (3-2, 6-diethylaniline) (M-CDEA), 4-methylenebis (2-isopropyl-6-methyl) aniline (M-MPA), 4-methylenebis (2-ethylaniline).

The molar ratio of the macromolecular dihydric alcohol, the dimethyl biphenyl diisocyanate to the micromolecular dihydric alcohol and/or the micromolecular diamine is 1: (1-5): (0.3 to 4), preferably 1: (1.5-4): (0.5 to 3).

The thermoplastic polyurethane elastomer containing the macromolecular diol, the dimethyl biphenyl diisocyanate and the micromolecular diol and/or micromolecular diamine chain segment has the molecular weight of 40000-100000, the molecular weight distribution of 1.2-1.9, the glass transition temperature of-25-15 ℃, the hardness range of 60 Shore A-95 Shore A, the loss factor tan delta max of 0.38-0.81, the loss factor at 0 ℃ of 0.31-0.71 and the loss factor at 60 ℃ of 0.02-0.05.

Another object of the present invention is to provide a method for preparing the above-mentioned wet skid resistant low rolling resistance thermoplastic polyurethane elastomer, which is characterized by comprising the following steps:

1) carrying out prepolymerization reaction on macromolecular diol and dimethyl biphenyl diisocyanate to obtain an isocyanate-terminated prepolymer; 2) adding a chain extender into the prepolymer obtained in the step 1) to carry out chain extension reaction to obtain the wet-skid-resistant low-rolling-resistance thermoplastic polyurethane elastomer.

Wherein the macrodiol is polyglycol, the molecular weight of the polyglycol is 650-4000, preferably 1000-2000, and the polyglycol is further selected from at least one of polyester diol, polycaprolactone diol, polycarbonate diol, polycaprolactone carbonate copolymer diol, polybutadiene diol and polylactic caprolactone copolymer diol;

the chain extender is selected from micromolecular dihydric alcohol and/or micromolecular diamine, wherein the micromolecular dihydric alcohol is selected from at least one of ethylene glycol, diethylene glycol, 1, 3-propylene glycol, 1, 4-Butanediol (BDO), 1, 6-Hexanediol (HDO), hydroquinone dihydroxyethyl ether (HQEE), resorcinol dihydroxyethyl ether (HER) and bisphenol A dihydroxyethyl ether; the small molecule diamine is at least one selected from 3, 3' -dichloro-4, 4 ' -diphenylmethane diamine (MOCA), 3, 5-dimethylthiotoluene diamine (DMTDA), 3, 5-diethyltoluene diamine, 4 ' -methylenebis (3-2, 6-diethylaniline) (M-CDEA), 4-methylenebis (2-isopropyl-6-methyl) aniline (M-MPA), 4-methylenebis (2-ethylaniline).

The molar ratio of the macromolecular diol to the dimethyl biphenyl diisocyanate to the chain extender is 1: 1-5: 0.3 to 4, preferably 1: 1.5-4: 0.5-3, and ensuring that the molar ratio of-NCO to-OH in the system is 1: 0.95-1.02.

Wherein, in the step 1), before the reaction of the macrodiol and the dimethylbiphenyl diisocyanate, the reaction is carried out, the water removal treatment is carried out, the water removal condition is that the stirring is carried out for 1 to 2.5 hours at 100 to 130 ℃ under the vacuum condition, and the stirring speed is 80 to 120r/min, and the operation is to remove the water in the raw materials;

in the step 1), a catalyst, an antioxidant and an anti-ultraviolet agent can be added, wherein the adding amount of the catalyst is 0.005-0.1 wt%, the adding amount of the antioxidant is 0.1-2 wt%, and the adding amount of the anti-ultraviolet agent is 0.1-2 wt% based on the mass of the macromolecular dihydric alcohol, the micromolecular dihydric alcohol and the dimethyl biphenyl diisocyanate; the adopted catalyst is at least one of an organic tin catalyst, an organic zinc catalyst and an organic bismuth catalyst, and preferably at least one of stannous octoate, dibutyltin diacetate, dibutyltin dilaurate, dibutyltin didodecyl sulfide, zinc isooctanoate and bismuth isooctanoate; the antioxidant is at least one of triethylene glycol bis [ beta- (3-tert-butyl-4-hydroxy-5-methylphenyl) propionate ] (antioxidant 245), pentaerythritol tetrakis [ beta- (3, 5-di-tert-butyl-4-hydroxyphenyl) propionate ] (antioxidant 1010) and 1,3, 5-trimethyl-2, 4,6- (3, 5-di-tert-butyl-4-hydroxybenzyl) benzene; the uvioresistant agent is at least one or two of 2- (2' -hydroxy-5 ' - (2, 4-tertiary butyl) phenyl) benzotriazole (UV320), 2' - (2' -hydroxy-3 ' -tertiary butyl-5 ' -methylphenyl) -5-chlorobenzotriazole (UV326), 2- (2' -hydroxy-3 ', 5' -di-tertiary butyl phenyl) -5-chlorobenzotriazole (UV327), 2- (2H-benzotriazol-2-yl) -6-dodecyl-4-cresol and 2- (2H-benzotriazol-2-yl) -6-dodecyl-4-methylphenol (UV 571);

the prepolymerization reaction conditions in the step 1) are as follows: the reaction temperature is 60-100 ℃, the stirring speed is 100-200 r/min, and the reaction time is 2-4 h under the normal pressure condition.

The chain extension reaction conditions in the step 2) are as follows: the reaction temperature is 70-100 ℃, the stirring speed is 200-500 r/min, and the reaction is carried out for 2-40 min under the condition of normal pressure;

and (3) further carrying out curing treatment on the thermoplastic polyurethane elastomer obtained in the step 2), wherein the specific operation is that the obtained thermoplastic polyurethane elastomer is heated for 16-24 hours at the temperature of 100-120 ℃ to obtain the final polyurethane elastomer.

The invention takes a chain segment containing macromolecular diol as a soft segment and a chain segment containing dimethyl diphenyl diisocyanate (TODI) and micromolecular diol and/or micromolecular diamine as a hard segment, and prepares a series of thermoplastic polyurethane elastomers based on TODI by a prepolymer method. The TODI has two methyl groups, so that the reaction activity is lower than that of TDI and MDI, and the steric effect of the methyl groups ensures that the obtained prepolymer is more stable, the molecular structure is symmetrical, the synthesized polyurethane has a good phase separation structure, excellent dynamic performance and good endogenous thermal performance, and the comprehensive performance of the polyurethane elastomer material can be improved.

The thermoplastic polyurethane elastomer provided by the invention has the number average molecular weight of 40000-100000, the PDI of 1.2-1.9, the glass transition temperature (Tg) of-25-15 ℃, the hardness of 60A-95A, the loss factor tan delta max of 0.38-0.81, the loss factor at 0 ℃ of 0.35-0.71, excellent wet-skid resistance, and the loss factor at 60 ℃ of 0.02-0.04, has the characteristic of low rolling resistance, and can perfectly solve the magic triangle problem of materials in the tire industry. In addition, the thermoplastic polyurethane elastomer has the tensile strength of 35-65MPa, the elongation at break of 550-850 percent, has the elasticity of rubber when in use, and can be directly processed into a molded product.

Compared with the prior art, the invention has the advantages that:

1) the wet-skid-resistant low-rolling-resistance thermoplastic polyurethane elastomer provided by the invention is obtained by adjusting the molecular weight of the macromolecular dihydric alcohol and the micromolecular dihydric alcohol and/or the micromolecular diamine and the molar ratio of reaction raw materials according to the application requirements of the molecular structure, the molecular weight and the processability of the thermoplastic polyurethane elastomer by taking the chain segment containing the macromolecular dihydric alcohol as a soft segment and taking the chain segment containing the dimethylbiphenyl diisocyanate (TODI) and the micromolecular dihydric alcohol and/or the micromolecular diamine as a hard segment;

2) the thermoplastic polyurethane elastomer material provided by the invention takes the structure containing the dimethyl biphenyl diisocyanate as a hard segment, so that the obtained prepolymer is more stable, the synthesized polyurethane has a good phase separation structure, has excellent performances of wet skid resistance, low rolling resistance, low heat generation and the like, and can perfectly solve the magic triangle problem of the material in the tire industry; moreover, the thermoplastic polyurethane elastomer has rubber elasticity when in use, can be directly processed into a product, does not need mixing and vulcanization like rubber, has obviously reduced processing energy consumption, can recycle leftover bits and pieces and waste materials, and is an important way for solving the problems of high energy consumption, high material consumption and high pollution of the traditional rubber;

3) the invention adopts a prepolymerization body method for synthesis, reduces the use and recovery of organic solvent, has simple and easy preparation method, low energy consumption and good repeatability, and reduces the pollution of industrial production to the environment.

Drawings

FIG. 1 is an IR spectrum, 2270cm, of example 1 to 3^-1There was no absorption peak, confirming that the-NCO group reaction was complete.

FIG. 2 is a DSC curve of examples 1 to 3, which shows that the sample Tg is in the range of-25 to-15 ℃, the soft segment is not crystallized, and the hard segment gradually shows a melting absorption peak with the increase of the content.

FIG. 3 shows the DMA curves of examples 1 to 3, with a loss factor at 0 ℃ of >0.3 (excellent wet skid resistance) and a loss factor at 60 ℃ of <0.05 (low rolling resistance).

FIG. 4 is a TMA curve showing that the softening point temperature increases with the increase of the hard segment content in examples 1 to 3.

Detailed Description

While the present invention will be described in detail with reference to the following examples, it should be understood that the following examples are illustrative of the present invention and are not to be construed as limiting the scope of the present invention.

The test items and test conditions of the thermoplastic polyurethane elastomers obtained in the examples were as follows:

and (3) infrared testing: the polyurethane prepared was analyzed by means of Fourier transform infrared spectroscopy model TENSOR27 from Bruker, with a test range of 4000-^-1The chemical structure of the polyurethane elastomer was tested using ATR-IR mode.

Gel Permeation Chromatography (GPC) test: the solvent was N, N-dimethylacetamide and the calibrator was polystyrene and equipped with a differential refractive index detector and three chromatography columns (Styragel HT3, 4 and 5) with a maximum flow rate of 22.5mL and the retention time of the polymer in the columns was tested.

DSC test: differential Scanning Calorimetry (DSC) analysis was performed using the STARe system from Mettler Toledo, Switzerland, the temperature rise and fall rates during the test were set at 10 deg.C/min, the sample mass was 10mg, nitrogen was used for protection, and the temperature scan range was-100 deg.C-280 deg.C

And (3) testing mechanical properties: the test is carried out according to the standard GB/T528-2009, the working area of the dumbbell-shaped splines is 25mm multiplied by 6mm, the tensile rate is 500 mm.min < -1 >, and 5 splines need to be tested in each group of experiments.

Test conditions for tear test: and testing according to the standard GB/T527- & 2008, selecting a right-angle tearing sample as a tearing sample, and testing 5 sample strips in each group of experiments.

Test conditions for shore a type hardness: and (4) testing according to the standard GB/T531.1-2008, wherein 5 points are required to be selected for each group of experiments, and the test results are averaged.

Dynamic thermomechanical analysis (DMA) was tested using the following conditions: a tensile mode with strain of 0.1%, frequency of 10Hz, heating rate of 3 ℃ min-1 and test temperature range of-125 ℃;

dynamic thermomechanical analysis (TMA) was tested using the following conditions: the test probe is in a cylindrical form, 1N constant external force is applied, the temperature rise rate is 5 ℃ min < -1 >, and the test temperature range is 30-260 DEG C

The sources of raw materials used in the following examples are as follows: polycarbonate diol was a product of Japan department of Industrial society, polycaprolactone diol was a product of Japan xylonite, Inc., polycaprolactone carbonate copolyol was purchased from Shanghai Jidi chemical Co., Ltd, and butanediol was purchased from Shanghai Alatin Co., Ltd. The others are all common commercial products.

Example 1

This example provides a preparation method of a low hardness TODI-based thermoplastic polyurethane elastomer, in which polycaprolactone diol with Mn of 1000 is used as a soft segment, and dimethylbiphenyl diisocyanate (TODI) and 1, 4-Butanediol (BDO) are used as hard segments, and polycaprolactone diol is designed: the molar ratio of TODI and 1,4 butanediol was 1:1.7:0.7 (molar ratio), and TODI-based thermoplastic polyurethane elastomers were prepared by a prepolymer method:

(1) removing water from 132g polycaprolactone diol (Mn 1000) under-0.097 MPa and 100 deg.C under mechanical stirring at 90r/min for 1.0h, and removing water from the raw materials;

(2) cooling the system to 60 ℃, adding 59.57g of dimethyl biphenyl diisocyanate and 0.01g of dibutyltin dilaurate serving as a catalyst, heating the system to be stable to 60 ℃, and reacting for 2h to obtain an isocyanate-terminated TODI-based polyurethane prepolymer;

(3) adding 8.43g of chain extender BDO, 0.2g of 2- (2 '-hydroxy-5' - (2, 4-tert-butyl) phenyl) benzotriazole (UV320) and 0.2g of tetra [ beta- (3, 5-di-tert-butyl-4-hydroxyphenyl) propionic acid ] pentaerythritol ester (antioxidant 1010) under the mechanical stirring of 400r/min, ensuring that the molar ratio of-NCO: -OH in a system is 1:1, reacting for 3min, taking out a product, and standing in an oven at 100 ℃ for 16h to obtain a TODI thermoplastic polyurethane elastomer finished product.

Example 2

This example provides a preparation method of a high hardness TODI-based thermoplastic polyurethane elastomer, in which polycaprolactone diol with Mn of 1000 is used as a soft segment, dimethylbiphenyl diisocyanate (TODI) and BDO are used as hard segments, and polycaprolactone diol TODI: BDO of 1:2.5:1.5 (molar ratio) is designed, and the TODI-based thermoplastic polyurethane elastomer is prepared by a prepolymer method:

(1) removing water from 111.2g polycaprolactone diol (Mn 1000) as soft segment under-0.097 MPa and 110 deg.C under mechanical stirring at 110r/min for 1.5h to remove water;

(2) cooling the system to 80 ℃, adding 73.68g of dimethyl biphenyl diisocyanate and 0.02g of dibutyltin diacetate serving as a catalyst, heating the system to be stable to 80 ℃, and reacting for 3h to obtain an isocyanate-terminated TODI-based polyurethane prepolymer;

(3) under the mechanical stirring of 400r/min, 15.11g of BDO, 1.6g of 2- (2 '-hydroxy-5' - (2, 4-tert-butyl) phenyl) benzotriazole (UV320) and 1.6g of diethylene glycol bis [ beta- (3-tert-butyl-4-hydroxy-5-methylphenyl) propionate ] (antioxidant 245) are added, the molar ratio of-NCO: -OH in a system is ensured to be 1:1, and after 3min of reaction, a product is taken out and placed in an oven at 110 ℃ for 18h to obtain a TODI thermoplastic polyurethane elastomer finished product.

Example 3

The preparation method comprises the following steps of (1) designing polycaprolactone diol with Mn being 1000 as a soft segment and dimethyl diphenyl diisocyanate (TODI) and BDO as a hard segment, wherein the molar ratio of the polycaprolactone diol to the BDO being 1:3.5:2.5, and preparing a TODI-based thermoplastic polyurethane elastomer by a prepolymer method:

(1) removing water from 93g polycaprolactone diol serving as a soft segment (Mn is 1000) under the conditions of-0.095 MPa and 120 ℃ and mechanical stirring at 120r/min for 2.5h, and removing water in the raw materials;

(2) after the temperature of the system is reduced to 90 ℃, 86.03g of dimethyl biphenyl diisocyanate and 0.03g of zinc isooctanoate serving as a catalyst are added, the temperature of the system is raised to 90 ℃ stably, and then the reaction is carried out for 3 hours, so that the isocyanate-terminated TODI-based polyurethane prepolymer is obtained;

(3) adding 20.96g of BDO, 1g of 2- (2 '-hydroxy-5' - (2, 4-tert-butyl) phenyl) benzotriazole (UV320) and 1g of tetra [ beta- (3, 5-di-tert-butyl-4-hydroxyphenyl) propionic acid ] pentaerythritol ester (antioxidant 1010) under the mechanical stirring of 400r/min, ensuring that the molar ratio of-NCO: -OH in a system is 1:1, reacting for 3min, taking out a product, and placing in an oven at 120 ℃ for 20h to obtain a TODI thermoplastic polyurethane elastomer finished product.

Example 4

The preparation method comprises the following steps of designing polycaprolactone carbonate copolymer glycol by taking Mn (2000) -polycaprolactone carbonate copolymer glycol as a soft segment and dimethyl diphenyl diisocyanate (TODI) and hydroquinone dihydroxyethyl ether (HQEE) as a hard segment, wherein TODI (1: 2: 1) and HQEE are respectively used as the soft segment, and preparing a TODI-based thermoplastic polyurethane elastomer by a prepolymer method:

(1) removing water from 145g of Mn-2000 polycaprolactone carbonic acid copolymerized glycol serving as a soft segment under the conditions of-0.097 MPa and 120 ℃ and mechanical stirring at 120r/min for 1.5h, and removing water in the raw materials;

(2) after the temperature of the system is reduced to 60 ℃, 39.62g of dimethyl biphenyl diisocyanate and 0.03g of catalyst bismuth isooctanoate are added, the temperature of the system is raised to 77 ℃ stably, and then the reaction is carried out for 3h, so as to obtain an isocyanate-terminated TODI-based polyurethane prepolymer;

(3) under the mechanical stirring of 400r/min, 15.37g of HQEE, 1g of 2- (2H-benzotriazole-2-yl) -6-dodecyl-4-methylphenol (UV571) and 1g of tetra [ beta- (3, 5-di-tert-butyl-4-hydroxyphenyl) propionic acid ] pentaerythritol ester (antioxidant 1010) are added, the molar ratio of-NCO: -OH in a system is ensured to be 1:1, and after 3min of reaction, a product is taken out and placed in a 120 ℃ oven for 16H to obtain a TODI thermoplastic polyurethane finished product.

Example 5

Taking polylactic acid caprolactone copolymerized diol with Mn of 3000 as a soft segment and dimethyl diphenyl diisocyanate (TODI) and 1, 6-Hexanediol (HDO) as a hard segment, designing the polylactic acid caprolactone copolymerized diol with TODI: HDO of 1:4:3 (molar ratio), and preparing the TODI-based thermoplastic polyurethane elastomer by a prepolymer method:

(1) using 136g of caprolactone polylactic acid copolymerized dihydric alcohol with Mn of 3000 as a soft segment, and removing water for 1.5h under the conditions of-0.095 MPa and 120 ℃ and mechanical stirring at 120r/min, thereby removing water in the raw materials;

(2) cooling the system to 60 ℃, adding 47.92g of dimethyl biphenyl diisocyanate and 0.01g of dibutyltin dilaurate serving as a catalyst, heating the system to be stable to 77 ℃, and reacting for 3 hours to obtain an isocyanate-terminated TODI-based polyurethane prepolymer;

(3) under the mechanical stirring of 400r/min, 1g of hydroquinone dihydroxyethyl ether (HQEE), 1g of 2- (2 '-hydroxy-5' - (2, 4-tert-butyl) phenyl) benzotriazole (UV320) and 1g of tetra [ beta- (3, 5-di-tert-butyl-4-hydroxyphenyl) propionic acid ] pentaerythritol ester (antioxidant 1010) are added, the molar ratio of-NCO: -OH in a system is ensured to be 1:1, and after 3min of reaction, a product is taken out and placed in an oven at 100 ℃ for 20h to obtain a TODI thermoplastic polyurethane finished product.

Example 6

Using Mn ═ 2000 polybutadiene diol as a soft segment, using dimethylbiphenyl diisocyanate (TODI) and 3,3 '-dichloro-4, 4' -diphenylmethane diamine (MOCA) as a hard segment, designing polybutadiene diol: TODI: MOCA ═ 1:2:1 (molar ratio), and preparing the TODI-based thermoplastic polyurethane elastomer by a prepolymer method:

(1) removing water from 142g of Mn 2000 polybutene diol as soft segment under the conditions of-0.095 MPa and 120 ℃ and mechanical stirring at 120r/min for 1.5h, and removing water in the raw material;

(2) cooling the system to 60 ℃, adding 38.25g of dimethyl biphenyl diisocyanate and 0.01g of dibutyltin dilaurate serving as a catalyst, heating the system to be stable to 77 ℃, and reacting for 3 hours to obtain an isocyanate-terminated TODI-based polyurethane prepolymer;

(3) adding 19.74g of MOCA, 0.2g of 2- (2 '-hydroxy-5' - (2, 4-tert-butyl) phenyl) benzotriazole (UV320) and 0.2g of tetra [ beta- (3, 5-di-tert-butyl-4-hydroxyphenyl) propionic acid ] pentaerythritol ester (antioxidant 1010) under the mechanical stirring of 400r/min, ensuring that the molar ratio of-NCO: -OH in a system is 1:1, reacting for 3min, taking out a product, and placing in an oven at 100 ℃ for 20h to obtain a TODI thermoplastic polyurethane finished product.

Example 7

The thermoplastic polyurethane elastomers obtained in examples 1 to 6 were tested for their properties such as molecular weight, glass transition temperature, tensile strength, elongation at break, and tear strength, and examples 1 to 6 were compared with comparative examples 1 to 2 using conventional green tire material HT166 (Shandong exquisite tire Co., Ltd.) as comparative example 1 and commercially available TPU (thermoplastic polyurethane C85A HPM, Pasteur, Germany) as comparative example 2, and the test data are shown in Table 1.

TABLE 1 polyurethane elastomer test data obtained in examples 1-6 and comparative examples 1-2

The GPC and infrared tests prove that the thermoplastic polyurethane elastomer with the molecular weight of more than 60000 is obtained, and the tests prove that the thermoplastic polyurethane synthesized by the TODI has the characteristics of excellent wet skid resistance and low rolling resistance, so that the TODI-based thermoplastic polyurethane elastomer synthesized by the invention can be applied to tires and solves the restriction of magic triangles of the tires. The mechanical property of the polyurethane elastomer synthesized by the invention is better than that of a rubber tire and a commercially available TPU, the rolling resistance is better than that of the rubber tire in a comparative example 1 and that of the commercially available TPU in a comparative example 2, the problem of magic triangles is better solved than that of the rubber tire and that of the commercially available TPU, and the polyurethane elastomer can be repeatedly utilized and is beneficial to environmental protection.