Polyurethane shoe material and preparation method thereof

Abstract

The invention provides a polyurethane shoe material and a preparation method thereof. The polyurethane shoe material is prepared from the following raw materials in parts by weight: 90 to 99 parts of hydroxyl-terminated thermoplastic polyurethane, 0.5 to 8 parts of modified styrene polymer, 0 to 1 part of compatilizer and 0 to 1 part of assistant. The modified styrene polymer is a styrene polymer which is modified by a rare earth material and has hydroxyl. The auxiliary agent at least comprises at least one of a plasticizer, an anti-hydrolysis agent and an antioxidant. According to the present invention, the thermoplastic polyurethane is the hydroxyl-terminated, the styrene polymer contains the hydroxyl, and the thermoplastic polyurethane, the styrene polymer and the rare earth material can be compatible through the hydrogen-bond interaction formed by the hydroxyl of the thermoplastic polyurethane and the styrene polymer, such that the problem of non-uniform dispersion or local agglomeration of the rare earth compound in the thermoplastic polyurethane can be avoided; the preparation raw materials of the polyurethane shoe material contain the styrene polymer which is modified by the rare earth material and has hydroxyl, and the styrene polymer has good compatibility with the main raw material thermoplastic polyurethane, so that the wear resistance and the skid resistance of the shoe material can be effectively improved.

Description

Technical Field

[0001] The invention relates to the technical field of polyurethane materials, in particular to polyurethane shoe materials and preparation methods thereof. Background Art

[0002] Thermoplastic polyurethane has good processability, weather resistance, and environmental protection, so it is widely used in the fields of shoes, pipes, films, rollers, cables and wires. Wear resistance and anti-skid performance are important indicators of shoe materials. Friction and wear will inevitably occur during use, which are closely related to the failure and safety performance of the material. As a major shoe-producing country, my country's consumption is very considerable. Improving the wear resistance of shoe materials can bring considerable economic and social benefits.

[0003] Usually, the wear resistance of shoe materials is improved by converting single materials into composite materials and adding reinforcing materials such as particles, whiskers and fibers to the materials to improve wear resistance. Adding a certain amount of rare earth compounds to resin or rubber materials can greatly improve the wear resistance of resin or rubber materials. However, rare earth compounds cannot be evenly distributed in resin or rubber materials, especially when the content is high, rare earth particles are prone to local agglomeration and cause stress concentration, which in turn reduces the strength of the sample and reduces the wear resistance.

[0004] Therefore, a new type of polyurethane shoe material is urgently needed to meet the needs of high wear resistance and anti-slip properties. Summary of the invention

[0005] The object of the present invention is to provide a polyurethane shoe material and a preparation method thereof. The raw materials for preparing the polyurethane shoe material contain a styrene polymer modified by a rare earth material and having a hydroxyl group, which has good compatibility with the main raw material thermoplastic polyurethane and can effectively improve the wear resistance and anti-slip properties of the shoe material.

[0006] To achieve the above object, the present invention provides a polyurethane shoe material on one hand. In terms of weight, the raw materials for preparing the polyurethane shoe material include 90 to 99 parts of hydroxyl-terminated thermoplastic polyurethane, 0.5 to 8 parts of modified styrene polymer, 0 to 1 part of compatibilizer and 0 to 1 part of auxiliary agent. The modified styrene polymer is a styrene polymer modified by a rare earth material and having a hydroxyl group. The auxiliary agent includes at least one of a plasticizer, an anti-hydrolysis agent and an antioxidant.

[0007] In the technical solution adopted by the present invention, the mechanical properties of the shoe material can be improved by introducing a styrene polymer on the basis of the main polyurethane material. In addition, the styrene polymer is modified by a rare earth material, and the microstructure of the polymer can be changed by doping with the rare earth material, and the interaction force between polymer molecules can be increased by coordination, thereby improving the mechanical properties of the polymer, so the wear resistance of the prepared material is greatly improved. The thermoplastic polyurethane is hydroxyl terminated, and the styrene polymer contains hydroxyl groups. The thermoplastic polyurethane, the styrene polymer and the rare earth material can be compatible through the hydrogen bonding formed by the hydroxyl groups of the two, so the problem of uneven dispersion or local agglomeration of rare earth compounds in the thermoplastic polyurethane can be avoided.

[0008] As a technical solution of the present invention, the modified styrene polymer is a hydroxystyrene-styrene copolymer modified by a rare earth material.

[0009] As a technical solution of the present invention, the hydroxyl value of the hydroxyl-terminated thermoplastic polyurethane is 30 to 60 mgKOH / g.

[0010] As one embodiment of the present invention, the hydroxyl value of the modified styrene-based polymer is 5 to 20 mgKOH / g.

[0011] As a technical solution of the present invention, the compatibilizer includes maleic anhydride grafted styrene and / or succinic anhydride grafted polyethylene.

[0012] As a technical solution of the present invention, the plasticizer includes at least one of dioctyl phthalate, acetyl tributyl citrate, dibutyl phthalate, dioctyl adipate and polybutadiene.

[0013] As a technical solution of the present invention, the anti-hydrolysis agent includes polycarbodiimide.

[0014] As a technical solution of the present invention, the antioxidant includes at least one of tert-butylhydroquinone, 2,6-di-tert-butyl-p-cresol, 2,6-tert-butyl-4-methylphenol, bis(3,5-tert-butyl-4-hydroxyphenyl)sulfide and pentaerythritol tetrakis[β-(3,5-tert-butyl-4-hydroxyphenyl)propionate.

[0015] Another aspect of the present invention provides a method for preparing a polyurethane shoe material, comprising the steps of:

[0016] (1) Synthesis of hydroxyl-terminated thermoplastic polyurethane

[0017] Add polyether polyol to the first reaction kettle, stir at 90-110°C to obtain material A, add diisocyanate to the second reaction kettle, stir at 60-80°C to obtain material B, add chain extender to the third reaction kettle, stir at 40-60°C to obtain material C, mix material A, material B and material C at high speed, and inject them into a twin-screw extruder with a catalyst for granulation;

[0018] (2) Synthesis of modified styrene polymers

[0019] In a reactor, rare earth metal compounds, initiators, styrene and hydroxystyrene are mixed according to a formula ratio, degassed, prepolymerized at 40-70°C, then gradually heated to 90-120°C, and kept warm for a certain period of time until polymerization is complete;

[0020] (3) Mixing and Injection Molding

[0021] Add the end-capped thermoplastic polyurethane, modified styrene polymer, compatibilizer and auxiliary agent in a formula amount into an internal mixer, heat and internally knead to obtain a mixture, and after internal kneading, use an injection molding machine to injection mold the mixture.

[0022] The raw materials involved in the preparation method of the invention are simple and easy to obtain, and the operation is simple. The prepared hydroxyl-terminated thermoplastic polyurethane has better water resistance and mechanical energy, and the modified styrene polymer has a higher hydroxyl value and better wear resistance.

[0023] As a technical solution of the present invention, the polyether polyol is obtained by polymerizing a dibasic acid, a diol and a small molecule polyether polyol.

[0024] As a technical solution of the present invention, the number average molecular weight of the polyether polyol is 800-2000.

[0025] As a technical solution of the present invention, the diisocyanate is 4,4'-diphenylmethane diisocyanate, toluene diisocyanate or isophorone diisocyanate.

[0026] As a technical solution of the present invention, the chain extender is a small molecule diol with 2 to 5 carbon atoms.

[0027] As a technical solution of the present invention, the catalyst includes an organic tin catalyst or an organic bismuth catalyst.

[0028] As a technical solution of the present invention, the rare earth metal compound includes an organic praseodymium compound or an organic neodymium compound.

[0029] As a technical solution of the present invention, the initiator includes azobisisobutyronitrile, azobisisoheptanenitrile or dimethyl azobisisobutyrate.

[0030] As a technical solution of the present invention, the mass ratio of the rare earth metal compound, the initiator, styrene and hydroxystyrene is 0.1-5.0: 0.01-0.5: 100: 5-30. DETAILED DESCRIPTION

[0031] The raw materials for preparing the polyurethane shoe material of the present invention include hydroxyl-terminated thermoplastic polyurethane, modified styrene polymer, compatibilizer and auxiliary agent.

[0032] Wherein, hydroxyl-terminated thermoplastic polyurethane is used as the main raw material, accounting for 90-99 parts of the raw materials for preparation, and its content may be but not limited to 90 parts, 91 parts, 92 parts, 93 parts, 94 parts, 95 parts, 96 parts, 97 parts, 98 parts, 99 parts of the raw materials for preparation. The hydroxyl value of hydroxyl-terminated thermoplastic polyurethane is 30-60 mgKOH / g. As an example, the hydroxyl value may be but not limited to 30 mgKOH / g, 35 mgKOH / g, 40 mgKOH / g, 45 mgKOH / g, 50 mgKOH / g, 55 mgKOH / g, 60 mgKOH / g.

[0033] The synthesis of hydroxyl-terminated thermoplastic polyurethane may include: adding polyether polyol into a first reaction kettle, stirring at a temperature of 90 to 110° C. to obtain material A, adding diisocyanate into a second reaction kettle, stirring at a temperature of 60 to 80° C. to obtain material B, adding a chain extender into a third reaction kettle, stirring at a temperature of 40 to 60° C. to obtain material C, and injecting material A, material B and material C into a twin-screw extruder after high-speed mixing with a catalyst for granulation.

[0034] Polyether polyol is obtained by polymerization of dibasic acid, diol and small molecule polyether polyol. The introduction of small molecule polyether polyol during synthesis can introduce soft segment structure into the molecular chain segment of hydroxyl-terminated thermoplastic polyurethane to improve hydrolysis resistance while maintaining high mechanical properties. The dibasic acid can be adipic acid, glutaric acid, oxalic acid, etc. The diol can be hexanediol, pentanediol, etc. The molar ratio of dibasic acid to diol is 1.10-1.15:1, and the weight of small molecule polyether polyol is 3-25% of the total weight of small molecule polyether polyol and diol. The number average molecular weight of polyether polyol is 800-2000. The diisocyanate is 4,4' diphenylmethane diisocyanate, toluene diisocyanate or isophorone diisocyanate. The chain extender is a small molecule diol with 2 to 5 carbon atoms, which may be, but not limited to, ethylene glycol, 1,4-butanediol, 1,3-propylene glycol, 1,2-propylene glycol or diethylene glycol. The catalyst includes an organic tin catalyst or an organic bismuth catalyst, which may be, but not limited to, stannous octoate, dibutyltin dilaurate or bismuth neodecanoate.

[0035] The modified styrene polymer accounts for 0.5 to 8 parts of the raw materials for preparation, and its content may be, but is not limited to, 0.5, 1, 2, 3, 4, 5, 6, 7, and 8 parts of the raw materials for preparation. The modified styrene polymer is a styrene polymer modified by a rare earth material and having a hydroxyl group. Further, the modified styrene polymer is a hydroxystyrene-styrene copolymer modified by a rare earth material. The hydroxyl value of the modified styrene polymer is 5 to 20 mgKOH / g. As an example, the hydroxyl value may be, but is not limited to, 5 mgKOH / g, 8 mgKOH / g, 10 mgKOH / g, 12 mgKOH / g, 14 mgKOH / g, 16 mgKOH / g, 18 mgKOH / g, and 20 mgKOH / g.

[0036] The synthesis of modified styrene polymers may include: mixing rare earth metal compounds, initiators, styrene and hydroxystyrene in a reactor according to a formula ratio, degassing, prepolymerizing at 40-70°C, and then gradually heating to 90-120°C, and keeping warm for a certain period of time until the polymerization is complete. Rare earth metal compounds include organic praseodymium compounds or organic neodymium compounds. Initiators include azobisisobutyronitrile, azobisisoheptanenitrile or dimethyl azobisisobutyrate. The mass ratio of rare earth metal compounds, initiators, styrene and hydroxystyrene is 0.1-5.0:0.01-0.5:100:5-30. Under the action of the initiator, the rare earth metal compound modifies styrene, changes the microstructure of the polymer by doping with the rare earth metal compound, and increases the interaction between polymer molecules by the coordination of the rare earth metal, which can not only improve the thermal stability of the polymer, but also improve the mechanical properties of polyethylene such as wear resistance. Hydroxystyrene is introduced into the copolymerization on the basis of styrene polymerization, and its hydroxyl group forms hydrogen bond with the hydroxyl group in hydroxyl-terminated thermoplastic polyurethane, which can improve the compatibility between hydroxyl-terminated thermoplastic polyurethane and modified styrene polymer.

[0037] The hydroxyl-terminated thermoplastic polyurethane of the present invention and the modified styrene polymer have good compatibility, so a compatibilizer may be added or not. The content of the compatibilizer in the raw materials for preparation may be, but is not limited to, 0 part, 0.1 part, 0.2 part, 0.3 part, 0.4 part, 0.5 part, 0.6 part, 0.7 part, 0.8 part, 0.9 part, 1.0 part. The compatibilizer includes maleic anhydride grafted styrene and / or succinic anhydride grafted polyethylene.

[0038] The raw materials for preparing the polyurethane shoe material of the present invention may further include auxiliary agents, which include at least one of plasticizers, anti-hydrolysis agents and antioxidants. The content of the auxiliary agents in the raw materials may be, but is not limited to, 0, 0.1, 0.2, 0.3, 0.4, 0.5, 0.6, 0.7, 0.8, 0.9, and 1.0 parts. The plasticizer includes at least one of dioctyl phthalate, tributyl acetyl citrate, dibutyl phthalate, dioctyl adipate, and polybutadiene. The anti-hydrolysis agent includes polycarbodiimide, which can protect polyurethane from hydrolysis. The antioxidant includes at least one of tert-butylhydroquinone, 2,6-di-tert-butyl-p-cresol, 2,6-tert-butyl-4-methylphenol, bis(3,5-tert-butyl-4-hydroxyphenyl)sulfide and pentaerythritol tetrakis[β-(3,5-tert-butyl-4-hydroxyphenyl)propionate.

[0039] The preparation method of the polyurethane shoe material of the present invention may include adding a formula amount of blocked thermoplastic polyurethane, modified styrene polymer, compatibilizer and auxiliary agent into an internal mixer, heating and internal mixing to obtain a mixture, and after internal mixing, injection molding the mixture using an injection molding machine.

[0040] In order to better illustrate the purpose, technical scheme and beneficial effects of the present invention, the present invention will be further described below in conjunction with specific embodiments. It should be noted that the following implementation method is a further explanation of the present invention and should not be used as a limitation of the present invention.

[0041] Synthesis of Hydroxyl-Terminated Thermoplastic Polyurethane A1:

[0042] (1) Synthesis of polyetherester polyols

[0043] Adipic acid and hexanediol are added to a reactor in the same molar ratio, heated and stirred, and then a small molecule polyether polyol with a number average molecular weight of 500 and a functionality of 2 is added, the small molecule polyether polyol accounts for 10% of the total weight of the small molecule polyether polyol and hexanediol, and nitrogen protection is passed through the reaction vessel to control the reaction temperature to 100°C, and tetrabutyl titanate accounting for 0.005% of the total weight of adipic acid, hexanediol and small molecule polyether polyol is added. The temperature is raised to 200°C, and after reacting for 3 hours, a nitrogen bubbling process is used to remove the water produced by the condensation. When the acid value of the material in the reactor is less than 0.6 mgKOH / g and the water content is below 0.05%, the temperature is lowered and the material is discharged to obtain a polyether ester polyol with a number average molecular weight of 1800.

[0044] (2) Synthesis of polyurethane

[0045] Add polyether polyol into the first reactor and stir at 100°C to obtain material A; add isophorone diisocyanate into the second reactor and stir at 70°C to obtain material B; add 1,4-butanediol into the third reactor and stir at 50°C to obtain material C; mix material A, material B and material C at high speed and inject them into a twin-screw extruder with an organic tin catalyst for granulation to obtain hydroxyl-terminated thermoplastic polyurethane A1 with a hydroxyl value of 40 mgKOH / g.

[0046] Synthesis of hydroxyl-terminated thermoplastic polyurethane A2:

[0047] (1) Synthesis of polyetherester polyols

[0048] Adipic acid and hexanediol are added to a reactor at a molar ratio of 1.10:1, heated and stirred, and then a small molecule polyether polyol with a number average molecular weight of 800 and a functionality of 3 is added, the small molecule polyether polyol accounts for 20% of the sum of the weight of the small molecule polyether polyol and hexanediol, and nitrogen protection is passed through to control the reaction temperature to be 110°C, and tetrabutyl titanate accounting for 0.010% of the sum of the weight of adipic acid, hexanediol and the small molecule polyether polyol is added, the temperature is raised to 200°C, and after reacting for 3 hours, a nitrogen bubbling process is used to remove the water generated by the condensation. When the acid value of the material in the reactor is less than 0.6 mgKOH / g and the water content is below 0.05%, the temperature is lowered and the material is discharged to obtain a polyether ester polyol with a number average molecular weight of 2000.

[0049] (2) Synthesis of polyurethane

[0050] Add polyether polyol to the first reactor and stir at 110°C to obtain material A; add 4,4'-diphenylmethane diisocyanate to the second reactor and stir at 75°C to obtain material B; add diethylene glycol to the third reactor and stir at 55°C to obtain material C; mix material A, material B and material C at high speed and inject them into a twin-screw extruder with an organic bismuth catalyst for granulation to obtain hydroxyl-terminated thermoplastic polyurethane A2 with a hydroxyl value of 50 mgKOH / g.

[0051] Synthesis of modified styrene polymer B1: An organic praseodymium compound, azobisisobutyronitrile, styrene and hydroxystyrene were mixed in a reactor at a mass ratio of 1.0:0.05:100:8, degassed, prepolymerized at 60°C, and then gradually heated to 100°C and kept warm for 2 hours until polymerization was complete to obtain a modified styrene polymer B1 with a hydroxyl value of 8 mgKOH / g.

[0052] Synthesis of modified styrene polymer B2: In a reactor, an organic neodymium compound, azobisisoheptanenitrile, styrene and hydroxystyrene are mixed in a mass ratio of 3.0:0.1:100:5, degassed, prepolymerized at 50°C, and then gradually heated to 110°C. The temperature is kept for 1.5 hours until the polymerization is complete to obtain a modified styrene polymer B2 with a hydroxyl value of 5 mgKOH / g.

[0053] Synthesis of modified styrene polymer B3: Azobisisoheptanenitrile, styrene and hydroxystyrene were mixed in a reactor at a mass ratio of 0.1:100:5, degassed, prepolymerized at 50°C, and then gradually heated to 110°C. The temperature was kept for 1.5 hours until the polymerization was complete to obtain a modified styrene polymer B3 with a hydroxyl value of 5 mgKOH / g.

[0054] Example 1

[0055] This embodiment is a polyurethane shoe material and a preparation method thereof.

[0056] In parts by weight, the raw materials for preparing polyurethane shoe materials include 99 parts of hydroxyl-terminated thermoplastic polyurethane A1, 0.6 parts of modified styrene polymer B1, 0.05 parts of maleic anhydride grafted styrene, 0.1 parts of polycarbodiimide, 0.2 parts of acetyl tributyl citrate and 0.05 parts of 2,6-di-tert-butyl-p-cresol.

[0057] The preparation method of the polyurethane shoe material of this embodiment can be as follows: adding the blocked thermoplastic polyurethane A1, modified styrene polymer B1, maleic anhydride grafted styrene, polycarbodiimide, acetyl tributyl citrate and 2,6-di-tert-butyl-p-cresol into an internal mixer, heating and internal mixing to obtain a mixture, and after internal mixing, the mixture is injection molded by an injection molding machine.

[0058] Example 2

[0059] This embodiment is a polyurethane shoe material and a preparation method thereof.

[0060] In parts by weight, the raw materials for preparing polyurethane shoe materials include 99 parts of hydroxyl-terminated thermoplastic polyurethane A1, 0.6 parts of modified styrene polymer B2, 0.05 parts of maleic anhydride grafted styrene, 0.1 parts of polycarbodiimide, 0.2 parts of acetyl tributyl citrate and 0.05 parts of 2,6-di-tert-butyl-p-cresol.

[0061] The preparation method of the polyurethane shoe material of this embodiment can be as follows: adding the blocked thermoplastic polyurethane A1, modified styrene polymer B1, maleic anhydride grafted styrene, polycarbodiimide, acetyl tributyl citrate and 2,6-di-tert-butyl-p-cresol into an internal mixer, heating and internal mixing to obtain a mixture, and after internal mixing, the mixture is injection molded by an injection molding machine.

[0062] Example 3

[0063] This embodiment is a polyurethane shoe material and a preparation method thereof.

[0064] In parts by weight, the raw materials for preparing polyurethane shoe materials include 99 parts of hydroxyl-terminated thermoplastic polyurethane A2, 0.6 parts of modified styrene polymer B1, 0.05 parts of maleic anhydride grafted styrene, 0.1 parts of polycarbodiimide, 0.2 parts of acetyl tributyl citrate and 0.05 parts of 2,6-di-tert-butyl-p-cresol.

[0065] The preparation method of the polyurethane shoe material of this embodiment can be as follows: adding the blocked thermoplastic polyurethane A1, modified styrene polymer B1, maleic anhydride grafted styrene, polycarbodiimide, acetyl tributyl citrate and 2,6-di-tert-butyl-p-cresol into an internal mixer, heating and internal mixing to obtain a mixture, and after internal mixing, the mixture is injection molded by an injection molding machine.

[0066] Example 4

[0067] This embodiment is a polyurethane shoe material and a preparation method thereof.

[0068] In parts by weight, the raw materials for preparing polyurethane shoe materials include 99 parts of hydroxyl-terminated thermoplastic polyurethane A2, 0.6 parts of modified styrene polymer B2, 0.05 parts of maleic anhydride grafted styrene, 0.1 parts of polycarbodiimide, 0.2 parts of acetyl tributyl citrate and 0.05 parts of 2,6-di-tert-butyl-p-cresol.

[0069] The preparation method of the polyurethane shoe material of this embodiment can be as follows: adding the blocked thermoplastic polyurethane A1, modified styrene polymer B1, maleic anhydride grafted styrene, polycarbodiimide, acetyl tributyl citrate and 2,6-di-tert-butyl-p-cresol into an internal mixer, heating and internal mixing to obtain a mixture, and after internal mixing, the mixture is injection molded by an injection molding machine.

[0070] Example 5

[0071] This embodiment is a polyurethane shoe material and a preparation method thereof.

[0072] In parts by weight, the raw materials for preparing polyurethane shoe materials include 97 parts of hydroxyl-terminated thermoplastic polyurethane A1, 2.3 parts of modified styrene polymer B1, 0.1 parts of maleic anhydride grafted styrene, 0.2 parts of polycarbodiimide, 0.3 parts of acetyl tributyl citrate and 0.1 parts of 2,6-di-tert-butyl-p-cresol.

[0073] The preparation method of the polyurethane shoe material of this embodiment can be as follows: adding the blocked thermoplastic polyurethane A1, modified styrene polymer B1, maleic anhydride grafted styrene, polycarbodiimide, acetyl tributyl citrate and 2,6-di-tert-butyl-p-cresol into an internal mixer, heating and internal mixing to obtain a mixture, and after internal mixing, the mixture is injection molded by an injection molding machine.

[0074] Example 6

[0075] This embodiment is a polyurethane shoe material and a preparation method thereof.

[0076] In parts by weight, the raw materials for preparing polyurethane shoe materials include 99 parts of hydroxyl-terminated thermoplastic polyurethane A2, 0.6 parts of modified styrene polymer B1, 0.1 parts of succinic anhydride grafted polyethylene, 0.1 parts of polycarbodiimide, 0.1 parts of dibutyl phthalate and 0.1 parts of 2,6-tert-butyl-4-methylphenol.

[0077] The preparation method of the polyurethane shoe material of this embodiment can be as follows: adding the blocked thermoplastic polyurethane A1, modified styrene polymer B1, maleic anhydride grafted styrene, polycarbodiimide, acetyl tributyl citrate and 2,6-di-tert-butyl-p-cresol into an internal mixer, heating and internal mixing to obtain a mixture, and after internal mixing, the mixture is injection molded by an injection molding machine.

[0078] Comparative Example 1

[0079] This comparative example is a polyurethane shoe material and a preparation method thereof.

[0080] In parts by weight, the raw materials for preparing the polyurethane shoe material include 99.65 parts of hydroxyl-terminated thermoplastic polyurethane A1, 0.1 parts of polycarbodiimide, 0.2 parts of acetyl tributyl citrate and 0.05 parts of 2,6-di-tert-butyl-p-cresol.

[0081] The preparation method of the polyurethane shoe material of this comparative example can be as follows: adding the blocked thermoplastic polyurethane A1, polycarbodiimide, acetyl tributyl citrate and 2,6-di-tert-butyl-p-cresol into an internal mixer, heating and internal mixing to obtain a mixture, and after internal mixing, injection molding the mixture using an injection molding machine.

[0082] Comparative Example 2

[0083] This embodiment is a polyurethane shoe material and a preparation method thereof.

[0084] In parts by weight, the raw materials for preparing polyurethane shoe materials include 99 parts of hydroxyl-terminated thermoplastic polyurethane A1, 0.6 parts of polystyrene, 0.05 parts of maleic anhydride grafted styrene, 0.1 parts of polycarbodiimide, 0.2 parts of acetyl tributyl citrate and 0.05 parts of 2,6-di-tert-butyl-p-cresol.

[0085] The preparation method of the polyurethane shoe material of this embodiment can be as follows: adding end-capped thermoplastic polyurethane A1, polystyrene, maleic anhydride grafted styrene, polycarbodiimide, acetyl tributyl citrate and 2,6-di-tert-butyl-p-cresol into an internal mixer, heating and internal mixing to obtain a mixture, and after internal mixing, the mixture is injection molded by an injection molding machine.

[0086] Comparative Example 3

[0087] This embodiment is a polyurethane shoe material and a preparation method thereof.

[0088] In parts by weight, the raw materials for preparing polyurethane shoe materials include 99 parts of hydroxyl-terminated thermoplastic polyurethane A1, 0.6 parts of modified styrene polymer B3, 0.05 parts of maleic anhydride grafted styrene, 0.1 parts of polycarbodiimide, 0.2 parts of acetyl tributyl citrate and 0.05 parts of 2,6-di-tert-butyl-p-cresol.

[0089] The preparation method of the polyurethane shoe material of this embodiment can be as follows: adding the blocked thermoplastic polyurethane A1, the modified styrene polymer B3, maleic anhydride grafted styrene, polycarbodiimide, acetyl tributyl citrate and 2,6-di-tert-butyl-p-cresol into an internal mixer, heating and internal mixing to obtain a mixture, and after internal mixing, the mixture is injection molded by an injection molding machine.

[0090] The polyurethane shoe materials prepared in Examples 1 to 6 and Comparative Examples 1 to 3 were subjected to performance tests. The test methods are as follows. The test results are shown in Table 1.

[0091] Wear resistance test: The wear resistance test is carried out using the DIN 53516GB 9867 wear resistance test method.

[0092] Anti-slip test: Anti-slip test is carried out according to ASTM-F1677 standard.

[0093] Shore hardness: Tested in accordance with the national standard "GB / T 531.1-2008 Test method for indentation hardness of vulcanized rubber or thermoplastic rubber Part 1_Shore durometer method (Shore hardness) Shore hardness".

[0094] Tensile strength: Tested in accordance with the national standard "GB / T 528-2009 Determination of tensile stress-strain properties of vulcanized rubber or thermoplastic rubber".

[0095] Tear strength: Tested in accordance with the national standard "GB / T529-2008 Determination of tear strength of vulcanized rubber or thermoplastic rubber".

[0096] Table 1 Performance test results of polyurethane shoe materials of Examples 1 to 6 and Comparative Examples 1 to 3

[0097]

[0098] From the results in Table 1, it can be seen that in the raw materials for preparing the polyurethane shoe material of the present invention, adding a styrene polymer modified by a rare earth material and having a hydroxyl group on the basis of a hydroxyl-terminated thermoplastic polyurethane can make the prepared shoe material have better tensile strength and tear strength as well as better wear resistance and anti-slip properties.

[0099] Finally, it should be noted that the above embodiments are only used to illustrate the technical solution of the present invention rather than to limit the scope of protection of the present invention. Although the present invention is described in detail with reference to the preferred embodiments, it is not limited to those listed in the embodiments. Those skilled in the art should understand that the technical solution of the present invention can be modified or replaced by equivalents without departing from the essence and scope of the technical solution of the present invention.

Claims

1. A polyurethane shoe material, characterized in that: The raw materials for preparation include 90 to 99 parts of hydroxyl-terminated thermoplastic polyurethane, 0.5 to 8 parts of modified styrene polymer, 0 to 1 part of compatibilizer and 0 to 1 part of auxiliary agent in parts by weight. The modified styrene polymer is a styrene polymer modified by rare earth material and having hydroxyl group. The auxiliary agent includes at least one of a plasticizer, an anti-hydrolysis agent and an antioxidant.

2. The polyurethane shoe material according to claim 1, characterized in that: The modified styrene polymer is a hydroxystyrene-styrene copolymer modified by a rare earth material.

3. The polyurethane shoe material according to claim 1, characterized in that: The hydroxyl value of the hydroxyl-terminated thermoplastic polyurethane is 30 to 60 mgKOH / g.

4. The polyurethane shoe material according to claim 1, characterized in that: The modified styrene polymer has a hydroxyl value of 5 to 20 mgKOH / g.

5. The polyurethane shoe material according to claim 1, characterized in that: The compatibilizer includes maleic anhydride grafted styrene and / or succinic anhydride grafted polyethylene.

6. The polyurethane shoe material according to claim 1, characterized in that: The plasticizer includes at least one of dioctyl phthalate, acetyl tributyl citrate, dibutyl phthalate, dioctyl adipate and polybutadiene.

7. The polyurethane shoe material according to claim 1, characterized in that: The anti-hydrolysis agent includes polycarbodiimide.

8. The polyurethane shoe material according to claim 1, characterized in that: The antioxidant comprises at least one of tert-butylhydroquinone, 2,6-di-tert-butyl-p-cresol, 2,6-tert-butyl-4-methylphenol, bis(3,5-tert-butyl-4-hydroxyphenyl)sulfide and pentaerythritol tetrakis[β-(3,5-tert-butyl-4-hydroxyphenyl)propionate.

9. The method for preparing the polyurethane shoe material according to claims 1 to 8, characterized in that: Includes steps: (1) Synthesis of hydroxyl-terminated thermoplastic polyurethane Add polyether polyol to the first reaction kettle, stir at 90-110°C to obtain material A, add diisocyanate to the second reaction kettle, stir at 60-80°C to obtain material B, add chain extender to the third reaction kettle, stir at 40-60°C to obtain material C, mix material A, material B and material C at high speed, and inject them into a twin-screw extruder with a catalyst for granulation; (2) Synthesis of modified styrene polymers In a reactor, rare earth metal compounds, initiators, styrene and hydroxystyrene are mixed according to a formula ratio, degassed, prepolymerized at 40-70°C, then gradually heated to 90-120°C, and kept warm for a certain period of time until polymerization is complete; (3) Mixing and Injection Molding The blocked thermoplastic polyurethane, the modified styrene polymer, the compatibilizer and the auxiliary agent in a formula amount are added into an internal mixer, heated and internally kneaded to obtain a mixture, and after internal kneading, the mixture is injection molded by an injection molding machine.

10. The method for preparing polyurethane shoe materials according to claim 9, characterized in that: Includes at least one of the following features ① to ⑧: ① The polyether polyol is obtained by polymerization of dibasic acid, diol and small molecule polyether polyol; ② The number average molecular weight of the polyether polyol is 800 to 2000; ③ The diisocyanate is 4,4'-diphenylmethane diisocyanate, toluene diisocyanate or isophorone diisocyanate; ④ The chain extender is a small molecule diol with 2 to 5 carbon atoms; ⑤ The catalyst includes an organic tin catalyst or an organic bismuth catalyst; ⑥ The rare earth metal compound includes an organic praseodymium compound or an organic neodymium compound; ⑦ The initiator includes azobisisobutyronitrile, azobisisoheptanenitrile or dimethyl azobisisobutyrate; ⑧The mass ratio of the rare earth metal compound, initiator, styrene and hydroxystyrene is 0.1-5.0:0.01-0.5:100:5-30.

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