High-resilience polyurethane insole material and method of making same

Abstract

This invention relates to the field of polyurethane materials technology, specifically disclosing a high-resilience polyurethane insole material and its preparation method. The polyurethane insole material comprises component A and component B, with a mass ratio of component A to component B of 100:90-95. Component A comprises the following raw materials: polyether polyol EP-330NG, polytetrahydrofuran ether diol, modified prepolymer, ADH dispersion, 1,4-butanediol, cyclopentane, polyether-modified silicone oil, composite catalyst, and deionized water; component B is carbodiimide-modified MDI. The preparation method involves mixing components A and B under high pressure and injecting the mixture into a preheated mold. After mold closing and curing, the mixture is demolded, and then subjected to oven treatment and room temperature curing to obtain the product. This invention, through the synergistic effect of block polyester, modified prepolymer, and ADH dispersion, results in an insole material with high resilience, low compression set, and good durability and molding stability.

Description

Technical Field

[0001] This invention relates to the field of polyurethane materials technology, specifically to a high-resilience polyurethane insole material and its preparation method. Background Technology

[0002] Polyurethane materials are widely used in insoles, soles, and other cushioning and shock-absorbing products due to their advantages such as light weight, good elasticity, wear resistance, and ease of molding. For insole materials, in addition to high resilience, they are also required to have low compression set, good dimensional stability, and a comfortable feel under long-term repeated compression, so as to meet the comprehensive requirements of support, cushioning, and durability in daily wear and sports scenarios.

[0003] Existing polyurethane insole materials are typically prepared by reacting polyether polyols or polyester polyols with isocyanates. While traditional polyether-based polyurethane foams offer a degree of softness and processability, they generally suffer from a difficulty in simultaneously achieving optimal resilience and resistance to compression set. Especially after prolonged cyclic compression, they are prone to collapse, decreased support, and reduced comfort. On the other hand, while traditional polyester-based systems offer advantages in improving mechanical properties, they often suffer from a narrow processing window, high viscosity, poor foaming stability, and increased material brittleness, limiting their application in high-comfort insoles.

[0004] To improve the overall performance of polyurethane insole materials, existing technologies often employ methods such as introducing chain extenders, modified polyols, silicone oil foam stabilizers, inorganic nanofillers, and latent crosslinking components to regulate the system. However, existing solutions still have the following shortcomings: First, the compatibility between ordinary chain extenders and the polyurethane matrix is ​​limited, making it difficult to establish a stable and controllable microphase separation structure between flexible and rigid segments; second, some latent curing systems have high activation temperatures, which are incompatible with conventional insole post-curing processes, making it difficult to effectively form a reinforcing network at lower temperatures; third, while traditional bio-based polyols or single polyester modification schemes can partially improve flexibility or strength, their synergistic effect on improving material resilience, fatigue resistance, and compression set is limited; fourth, existing foaming systems are prone to problems such as uneven cell size, insufficient structural stability, and large batch-to-batch fluctuations in industrial continuous production.

[0005] Therefore, there is an urgent need to develop a high-resilience polyurethane insole material and its preparation method that combines high resilience, low compression set, good mechanical properties and a suitable processing window for industrial applications, which has important practical application value. Summary of the Invention

[0006] To address the challenges of achieving high resilience, cushioning, shock absorption, and impact resistance in existing polyurethane insole materials, this invention provides a high-resilience polyurethane insole material and its preparation method.

[0007] In a first aspect, the present invention provides a high-resilience polyurethane insole material, employing the following technical solution: A high-resilience polyurethane insole material, comprising component A and component B; wherein the mass ratio of component A to component B is 100:90-95.

[0008] Component A comprises the following raw materials in parts by weight: 30-35 parts of polyether polyol EP-330NG, 20-30 parts of polytetrahydrofuran ether diol, 20-25 parts of modified prepolymer, 10-12 parts of ADH dispersion, 4-6 parts of 1,4-butanediol, 3-4 parts of cyclopentane, 0.8-1 part of polyether modified silicone oil, 0.5-0.7 parts of composite catalyst, and 0.6-0.8 parts of deionized water; The modified prepolymer is prepared by chain extension of polymeric polyol, castor oil-modified polyol and block polyester via carbodiimide-modified MDI.

[0009] The composite catalyst is composed of bismuth neodecanoate and dimethylaminoethyl ether in a mass ratio of 3.5-4.5:3.

[0010] Component B is carbodiimide-modified MDI with an isocyanate content of 28-30%.

[0011] Preferably, the block polyester is prepared by the following method: A1. Under nitrogen protection, L-lactide is heated to 125-130℃ and completely melted. n-Butanol and zinc octanoate are added while stirring. After the addition is complete, the mixture is stirred to react. After the reaction is complete, the temperature is lowered to 115-120℃ to obtain hydroxyl-terminated polylactic acid. A2. Under stirring, ε-caprolactone is added to terminal hydroxyl polylactic acid. After the addition is complete, the temperature is raised to 125-130℃ and the reaction is stirred for 5-6 hours. After the reaction is completed, the mixture is cooled to room temperature, dichloromethane is added, and the mixture is stirred until completely dissolved. The solution is then poured into methanol to precipitate the precipitate. After filtration, washing, and drying, block polyester is obtained.

[0012] Preferably, in step A1, the mass ratio of L-lactide, n-butanol, and zinc octanoate is 28-32:4-5:0.16-0.2.

[0013] Preferably, in step A1, L-lactide is obtained through the following pretreatment: L-lactide and anhydrous ethanol are mixed at a mass ratio of 1:10, stirred at a temperature of 75-80℃ and a speed of 200-300 rpm until completely dissolved, cooled to 0-5℃ and allowed to stand for crystallization for 1-2 hours, filtered using a polytetrafluoroethylene filter membrane with a pore size of 0.45 μm, the filter cake is washed 2-3 times with anhydrous ethanol at 0-5℃, and then dried at a temperature of 40-50℃ and a vacuum degree ≤-0.095 MPa for 18-24 hours.

[0014] Preferably, in step A1, n-butanol and zinc octanoate are obtained by the following pretreatment: n-butanol is dried with 4Å molecular sieve for 20-24 h; zinc octanoate is dried at a temperature of 80-85℃ and a vacuum degree of ≤-0.095MPa for 2-3 h.

[0015] Preferably, in step A1, the stirring speed for adding n-butanol and zinc octanoate is 180-250 rpm.

[0016] Preferably, in step A1, the stirring reaction refers to stirring the reaction for 2.5-3.5 hours at a temperature of 125-130℃ and a rotation speed of 180-250 rpm.

[0017] Preferably, in step A2, the mass ratio of terminal hydroxyl polylactic acid to ε-caprolactone is 1:1.9-2.2.

[0018] Preferably, in step A2, ε-caprolactone is obtained by the following pretreatment: 0.02-0.04 wt% hydroquinone is added to ε-caprolactone, and vacuum distillation is carried out under the conditions of 12-18 mmHg absolute pressure and 125-135℃ distillation temperature. The fraction is collected and dried with 4Å molecular sieve for 24-28 h. Preferably, in step A2, the stirring speed for adding ε-caprolactone is 180-250 rpm.

[0019] Preferably, in step A2, the filtration, washing, and drying process refers to: filtering with a polytetrafluoroethylene filter membrane with a pore size of 0.45 μm, washing with methanol at 0-4℃ 2-3 times (each time the amount of methanol used is 1.5-2 times the volume of the precipitate), and drying to constant weight under the conditions of temperature 40-45℃ and vacuum degree ≤-0.095MPa.

[0020] Preferably, the modified prepolymer is prepared by the following method: B1. Under nitrogen protection, the polymer polyol, castor oil modified polyol, block polyester and 1,4-butanediol are mixed, vacuum dehydrated, cooled to 70-75℃, dibutyltin dilaurate is added, and stirred evenly to obtain a polyol mixture. B2. Under stirring, carbodiimide-modified MDI is added to the polyol mixture. After the addition is complete, the mixture is stirred at 78-80℃ for 3-4 hours. Hydroquinone monomethyl ether is then added, and stirring is continued for 10-15 minutes. The mixture is then cooled to room temperature to obtain the modified prepolymer.

[0021] Preferably, in step B1, the mass ratio of polymeric polyol, castor oil-modified polyol, block polyester, 1,4-butanediol and dibutyltin dilaurate is 80-90:4-6:10:10-12:0.04-0.06.

[0022] Preferably, in step B1, vacuum dehydration refers to dehydration for 1.5-2.5 hours under conditions of temperature 105-115℃ and vacuum degree ≤-0.095MPa.

[0023] Preferably, in step B1, "stirring evenly" means stirring for 10-20 minutes at a temperature of 70-75℃ and a rotation speed of 300-500 rpm.

[0024] Preferably, in step B2, the rotation speed of adding carbodiimide-modified MDI under stirring is 250-400 rpm.

[0025] Preferably, in step B2, the mass ratio of carbodiimide-modified MDI, polyol mixture, and hydroquinone monomethyl ether is 30:110-112:0.015-0.03.

[0026] Preferably, the ADH dispersion is prepared by the following method: C1. After vacuum dehydration of polyether polyol 330N, adipic acid dihydrazide and nano silica are added, and shear emulsification is performed to obtain a suspension. C2. Under stirring, isophorone diisocyanate is added to the suspension. After the addition is complete, the mixture is stirred and reacted at room temperature for 2-3 hours. After the reaction is complete, the mixture is degassed under vacuum to obtain an ADH dispersion.

[0027] Preferably, in step C1, vacuum dehydration refers to dehydration for 0.8-1.2 hours under conditions of 80-90℃ and vacuum degree ≤-0.09MPa.

[0028] Preferably, in step C1, the mass ratio of polyether polyol 330N, adipic acid dihydrazide, and nano silica is 65:28-32:2-3.

[0029] Preferably, in step C1, shear emulsification refers to shear emulsification for 15-25 minutes at a temperature of 35-45℃ and a rotation speed of 2000-3000 rpm.

[0030] Preferably, in step C2, the mass ratio of isophorone diisocyanate to suspension is 5-6:95-97.

[0031] Preferably, in step C2, "stirring" refers to stirring at room temperature and a stirring speed of 400-600 rpm.

[0032] Preferably, in step C2, vacuum degassing refers to degassing for 10-20 minutes under conditions of temperature 25-35℃ and vacuum degree ≤-0.090MPa.

[0033] Preferably, component A is prepared by the following method: Polyether polyol EP-330NG, polytetrahydrofuran ether diol, and 1,4-butanediol were mixed and dehydrated under vacuum. Then, under nitrogen protection and stirring, modified prepolymer, ADH dispersion, deionized water, polyether modified silicone oil, cyclopentane, and composite catalyst were added sequentially. The mixture was stirred until homogeneous and then degassed under vacuum to obtain component A.

[0034] Preferably, the term "uniform stirring" refers to: adding each component sequentially at a temperature of 25-35℃ and a rotation speed of 500-800 rpm, stirring for 5-8 minutes after each component is added, and continuing to stir at a rotation speed of 800-1000 rpm for 15-25 minutes after all components have been added.

[0035] Preferably, the vacuum degassing refers to degassing for 10-20 minutes under conditions of temperature 25-35℃ and vacuum degree ≤-0.090MPa.

[0036] Secondly, this invention provides a method for preparing a high-resilience polyurethane insole material, employing the following technical solution: A method for preparing a high-resilience polyurethane insole material includes the following steps: S1. Clean the cavity of the insole mold, spray with water-based release agent, preheat to 50-55℃ and keep warm for 30-40 minutes; S2. After preheating components A and B to 50-55℃ and holding them at that temperature for 30-40 minutes, inject them into the mold through a high-pressure mixing head, close the mold and cure for 4-5 minutes, demold and transfer to a drying tunnel at 60-70℃ for 35-40 minutes, and then let it stand at room temperature for 16-24 hours to obtain a high-resilience polyurethane insole material.

[0037] Preferably, in step S1, spraying refers to: using an atomizing spray gun to spray the water-based release agent 1-2 times at a spraying pressure of 0.20-0.30MPa and a distance of 10-20cm from the surface of the mold cavity, and letting it stand for 3-5 minutes after spraying to allow the release agent to form a film, controlling the dry film thickness to be 3-5μm.

[0038] Preferably, in step S2, the conditions for injecting the material into the mold through the high-pressure mixing head include: mixing head pressure of 125-135 bar and injection time of 3.5-4.5 s.

[0039] In summary, compared with the prior art, the present invention has the following beneficial effects: 1. This invention introduces a modified prepolymer, prepared by chain extension of block polyester with carbodiimide-modified MDI, into component A. This chain extender combines the flexibility of polyether segments, the structural regularity of bio-based components, and the polarity regulation of block polyester segments, thereby improving the controllability of the microphase separation structure and thus enhancing the resilience, support performance, and compression recovery ability of insole materials.

[0040] 2. This invention prepares block polyester by sequential ring-opening polymerization of L-lactide and ε-caprolactone, and introduces it into the modified prepolymer system. This enables the construction of a segmental structure with rigid-flexible synergistic characteristics in the polyurethane molecular chain. On the one hand, this is beneficial to improving the elastic recovery performance and mechanical strength of the insole material. On the other hand, it helps to reduce compression set and improve the dimensional stability and durability of the product under long-term cyclic pressure conditions.

[0041] 3. This invention prepares an ADH dispersion to stably introduce adipic acid dihydrazide into the polyurethane system in the form of a dispersed phase, and combines it with in-situ coating treatment with isophorone diisocyanate to improve the dispersion stability and reaction uniformity of ADH in the polyol system. In the subsequent molding and curing process, the ADH dispersion can form a synergistic reinforcing effect with the polyurethane system, thereby improving the fatigue resistance and resilience of the insole material.

[0042] 4. This invention achieves high-resilience polyurethane insole material by synergistically optimizing the formulation system of component A, the isocyanate index of component B, and the molding foaming process conditions. This material has good foaming fluidity, cell uniformity, and molding stability, and can achieve stable demolding with a short in-mold curing time. After post-curing, it obtains excellent resilience, comfort, and durability, making it suitable for industrial continuous production and insole product applications. Detailed Implementation

[0043] The present invention will be further described in detail below with reference to the embodiments.

[0044] For experiments not specifically described in the examples, the procedures or conditions should be followed according to the conventional experimental procedures described in the literature in this field. Reagents or instruments whose manufacturers are not specified are all commercially available conventional reagent products.

[0045] The key raw materials used in this invention are sourced from the following sources: Polyether-modified silicone oil: provided by Sichuan Sitiqi Technology Co., Ltd. Polyether polyol 330N: Brand: Langbowan, provided by Hubei Langbowan Biomedical Co., Ltd.; Polyether polyol EP-330NG: Brand: Lanxing Dongda, Model: EP-330NG, provided by Guangzhou Fufeng Chemical Technology Co., Ltd. Polytetrahydrofuran ether diol: Brand: Qiyun, CAS No.: 25190-06-1, provided by Shandong Qiyun Chemical Technology Co., Ltd.; Bismuth neodecanoate: Brand: Rongzheng, provided by Jinan Rongzheng Chemical Co., Ltd.; Dimethylaminoethyl ether: Brand: Shanghe, CAS No.: 3033-62-3, provided by Guangzhou Shanghe Chemical Technology Co., Ltd.; Polymer polyol: Brand: Lanxing Dongda, Model: POP36 / 28, provided by Guangzhou Fufeng Chemical Technology Co., Ltd.; Castor oil modified polyol: Brand: Ito, Model: URIC H-31, provided by Shanghai Huanyang Chemical Technology Co., Ltd.; Nano silica: Brand: Jiuli Biotechnology, Particle size: 30nm, Model: JL-SP30S, provided by Hangzhou Jiuli Biomaterials Co., Ltd. Carbodiimide-modified MDI: Brand: Wanhua, Model: CDMDI-100L, Isocyanate content: 28%, provided by Meizhou Fuxi Chemical Co., Ltd. Water-based release agent: Brand: Sihai, Model: 3186, provided by Shenzhen Branch of Hubei Longsheng Sihai New Materials Co., Ltd. Polycaprolactone diol: Brand: Fangyu, Model: PC2000, provided by Jining Fangyu Chemical Co., Ltd.

[0046] Examples 1-3 provide a high-resilience polyurethane insole material and its preparation method.

[0047] Example 1 Block polyesters are prepared by the following methods: A1. The mass ratio of L-lactide, n-butanol, and zinc octanoate is controlled at 28:4:0.16. The L-lactide is obtained through the following pretreatment: L-lactide and anhydrous ethanol are mixed at a mass ratio of 1:10, stirred at 75°C and 200 rpm until completely dissolved, cooled to 0°C, and allowed to stand for crystallization for 1 hour. The mixture is then filtered using a 0.45 μm polytetrafluoroethylene filter membrane. The filter cake is washed twice with anhydrous ethanol at 0°C and dried for 24 hours at 40°C and a vacuum degree ≤-0.095 MPa. The n-butanol is then... The n-butanol and zinc octanoate were dried using 4Å molecular sieves for 20 h. The n-butanol and zinc octanoate were pretreated as follows: n-butanol was dried using 4Å molecular sieves for 20 h; zinc octanoate was dried at 80 °C and vacuum degree ≤ -0.095 MPa for 3 h; L-lactide was heated to 125 °C and completely melted under nitrogen protection, and n-butanol and zinc octanoate were added at 180 rpm. After the addition was complete, the mixture was stirred at 125 °C and 180 rpm for 3.5 h. After the reaction was completed, the mixture was cooled to 118 °C to obtain hydroxyl-terminated polylactic acid. A2. The mass ratio of terminal hydroxyl polylactic acid (PLA) to ε-caprolactone is controlled at 1:1.9. The ε-caprolactone is obtained through the following pretreatment: 0.02 wt% hydroquinone is added to ε-caprolactone, and vacuum distillation is carried out under a pressure of 12 mmHg and a distillation temperature of 125 °C. The fraction is collected and dried with a 4 Å molecular sieve for 24 h. ε-caprolactone is added to terminal hydroxyl polylactic acid at a speed of 180 rpm, and the addition time is controlled at 30 min. After the addition is completed, the temperature is raised to 125 °C. The reaction was continued at ℃ for 6 hours. After the reaction was completed, it was cooled to room temperature, and dichloromethane was added until the solid content was 10wt%. The mixture was stirred for 20 minutes until completely dissolved. The solution was poured into methanol at 0℃ in a volume 5 times that of dichloromethane to precipitate the precipitate. The precipitate was filtered using a polytetrafluoroethylene filter membrane with a pore size of 0.45μm. The precipitate was washed twice with methanol at 0℃ (each time the amount of methanol was 1.5 times the volume of the precipitate). The precipitate was dried to constant weight at a temperature of 40℃ and a vacuum degree ≤-0.095MPa to obtain the block polyester. The modified prepolymer was prepared by the following method: B1. The mass ratio of polymer polyol, castor oil-modified polyol, block polyester, 1,4-butanediol and dibutyltin dilaurate is controlled at 80:4:10:10:0.04. Under nitrogen protection, the polymer polyol, castor oil-modified polyol, block polyester and 1,4-butanediol are mixed and dehydrated at 105℃ and vacuum degree ≤-0.095MPa for 2.5h. After cooling to 70℃, dibutyltin dilaurate is added and stirred at 70℃ and 300rpm for 20min to obtain a polyol mixture. B2. The mass ratio of carbodiimide-modified MDI, polyol mixture, and hydroquinone monomethyl ether was controlled at 30:110:0.015. Carbodiimide-modified MDI was added to the polyol mixture at 250 rpm, and the dropping time was controlled at 60 min. After the dropping was completed, the mixture was stirred at 78 °C for 4 h. Hydroquinone monomethyl ether was then added, and stirring was continued for 15 min. The mixture was then cooled to room temperature to obtain the modified prepolymer. The ADH dispersion was prepared by the following method: C1. The mass ratio of polyether polyol 330N, adipic acid dihydrazide and nano silica was controlled at 65:28:2. Polyether polyol 330N was dehydrated at 80℃ and vacuum degree ≤-0.09MPa for 1.2h. Then adipic acid dihydrazide and nano silica were added. The mixture was sheared and emulsified at 35℃ and 2000rpm for 25min to obtain a suspension. C2. Control the mass ratio of isophorone diisocyanate to suspension to be 5:95. Add isophorone diisocyanate to suspension at room temperature and 400 rpm. Control the dropping time to be 35 min. After the dropping is completed, continue stirring and reacting at room temperature for 3 h. After the reaction is completed, degas for 20 min at 25℃ and vacuum degree ≤-0.090MPa to obtain ADH dispersion. The composite catalyst is composed of bismuth neodecanoate and dimethylaminoethyl ether in a mass ratio of 3.5:3; Component A comprises the following raw materials in parts by weight: 30 parts of polyether polyol EP-330NG, 20 parts of polytetrahydrofuran ether diol, 20 parts of modified prepolymer, 10 parts of ADH dispersion, 4 parts of 1,4-butanediol, 3 parts of cyclopentane, 0.8 parts of polyether modified silicone oil, 0.5 parts of composite catalyst, and 0.6 parts of deionized water; Component A is prepared by the following method: Polyether polyol EP-330NG, polytetrahydrofuran ether diol, and 1,4-butanediol were mixed and dehydrated under vacuum. Then, under nitrogen protection, at a temperature of 25°C and a rotation speed of 500 rpm, modified prepolymer, ADH dispersion, deionized water, polyether modified silicone oil, cyclopentane, and composite catalyst were added sequentially. After each component was added, the mixture was stirred for 5 min. After all components were added, the mixture was stirred for another 25 min at a rotation speed of 800 rpm. The mixture was then degassed for 20 min at a temperature of 25°C and a vacuum degree of ≤-0.090 MPa to obtain component A. A high-resilience polyurethane insole material, comprising component A and component B; wherein the mass ratio of component A to component B is 100:90; Component B is carbodiimide-modified MDI with an isocyanate content of 28%. A method for preparing a high-resilience polyurethane insole material includes the following steps: S1. Clean the mold cavity of the insole. Use an atomizing spray gun to spray the water-based release agent once at a spraying pressure of 0.20MPa and a distance of 10cm from the surface of the mold cavity. After spraying, let it stand for 3 minutes to allow the release agent to form a film. Control the dry film thickness to 3μm. Preheat to 50℃ and keep warm for 40 minutes. S2. After preheating components A and B to 50°C and holding them at that temperature for 40 minutes, they are mixed through a high-pressure mixing head and then injected into the preheated mold cavity. The pressure of the high-pressure mixing head is 125 bar and the injection time is 4.5 seconds. After injection, the mold is closed and cured for 5 minutes. After demolding, the mold is transferred to a 60°C drying tunnel for 40 minutes and then left to stand at room temperature for 16 hours to obtain a high-resilience polyurethane insole material.

[0048] Example 2 Block polyesters are prepared by the following methods: A1. The mass ratio of L-lactide, n-butanol, and zinc octanoate is controlled at 30:4.5:0.18. The L-lactide is obtained through the following pretreatment: L-lactide and anhydrous ethanol are mixed at a mass ratio of 1:10, stirred at 78°C and 250 rpm until completely dissolved, cooled to 3°C, and allowed to crystallize for 1.5 h. The mixture is then filtered using a 0.45 μm polytetrafluoroethylene filter membrane. The filter cake is washed three times with anhydrous ethanol at 3°C, and then subjected to a process at 45°C and a vacuum degree ≤-0.095. Drying at MPa for 21 h; drying n-butanol with 4 Å molecular sieve for 22 h; drying zinc octanoate at 83 °C and vacuum ≤ -0.095 MPa for 2.5 h; heating L-lactide to 128 °C to completely melt under nitrogen protection, adding n-butanol and zinc octanoate at 200 rpm, stirring the reaction at 128 °C and 200 rpm for 3 h after the addition is complete, cooling to 115 °C to obtain hydroxyl-terminated polylactic acid; A2. The mass ratio of terminal hydroxyl polylactic acid (PLA) to ε-caprolactone is controlled at 1:2.1. The ε-caprolactone is obtained through the following pretreatment: 0.03 wt% hydroquinone is added to ε-caprolactone, and vacuum distillation is carried out under the conditions of 15 mmHg absolute pressure and 130 °C distillation temperature. The fraction is collected and dried with 4 Å molecular sieve for 26 h. ε-caprolactone is added to terminal hydroxyl polylactic acid at 200 rpm, and the addition time is controlled at 25 min. After the addition is completed, the temperature is raised to 128 °C. The reaction was stirred for another 5.5 hours. After the reaction was completed, the mixture was cooled to room temperature. Dichloromethane was added until the solid content was 13 wt%. The mixture was stirred for 18 minutes until completely dissolved. The solution was poured into methanol at 2°C in a volume 8 times that of dichloromethane to precipitate the precipitate. The precipitate was filtered through a polytetrafluoroethylene (PTFE) membrane with a pore size of 0.45 μm. The precipitate was washed three times with methanol at 2°C (each time the amount of methanol was 1.8 times the volume of the precipitate). The precipitate was dried to constant weight at 43°C and a vacuum degree ≤ -0.095 MPa to obtain the block polyester. The modified prepolymer was prepared by the following method: B1. The mass ratio of polymer polyol, castor oil-modified polyol, block polyester, 1,4-butanediol and dibutyltin dilaurate is controlled at 85:5:10:11:0.05. Under nitrogen protection, the polymer polyol, castor oil-modified polyol, block polyester and 1,4-butanediol are mixed and dehydrated at 110℃ and vacuum degree ≤-0.095MPa for 2 hours. After cooling to 73℃, dibutyltin dilaurate is added and stirred at 73℃ and 400rpm for 15 minutes to obtain a polyol mixture. B2. The mass ratio of carbodiimide-modified MDI, polyol mixture, and hydroquinone monomethyl ether was controlled at 30:111:0.023. Carbodiimide-modified MDI was added to the polyol mixture at 300 rpm, and the dropping time was controlled at 65 min. After the dropping was completed, the mixture was stirred at 79 °C for 3.5 h. Hydroquinone monomethyl ether was then added, and stirring was continued for 12.5 min. The mixture was then cooled to room temperature to obtain the modified prepolymer. The ADH dispersion was prepared by the following method: C1. The mass ratio of polyether polyol 330N, adipic acid dihydrazide and nano silica was controlled at 65:30:2.5. After dehydrating polyether polyol 330N at 85℃ and vacuum degree ≤-0.09MPa for 1h, adipic acid dihydrazide and nano silica were added. The mixture was sheared and emulsified at 40℃ and 2500rpm for 20min to obtain a suspension. C2. Controlling the mass ratio of isophorone diisocyanate to suspension at 5.5:96, isophorone diisocyanate was added to suspension at room temperature and 500 rpm, with a dropping time of 40 min. After the dropping was completed, the mixture was stirred and reacted at room temperature for 2.5 h. After the reaction was completed, the mixture was degassed for 15 min at 30℃ and a vacuum degree ≤-0.090 MPa to obtain ADH dispersion. The composite catalyst is composed of bismuth neodecanoate and dimethylaminoethyl ether in a mass ratio of 4:3; Component A comprises the following raw materials in parts by weight: 32.5 parts of polyether polyol EP-330NG, 25 parts of polytetrahydrofuran ether diol, 22 parts of modified prepolymer, 11 parts of ADH dispersion, 5 parts of 1,4-butanediol, 3.5 parts of cyclopentane, 0.9 parts of polyether modified silicone oil, 0.6 parts of composite catalyst, and 0.7 parts of deionized water; Component A is prepared by the following method: Polyether polyol EP-330NG, polytetrahydrofuran ether diol, and 1,4-butanediol were mixed and dehydrated under vacuum. Then, under nitrogen protection, at a temperature of 30°C and a rotation speed of 650 rpm, modified prepolymer, ADH dispersion, deionized water, polyether modified silicone oil, cyclopentane, and composite catalyst were added sequentially. After each component was added, the mixture was stirred for 6.5 min. After all components were added, the mixture was stirred for another 20 min at a rotation speed of 900 rpm. The mixture was then degassed for 15 min at a temperature of 30°C and a vacuum degree of ≤-0.090 MPa to obtain component A. A high-resilience polyurethane insole material, comprising component A and component B; wherein the mass ratio of component A to component B is 100:92.5; Component B is carbodiimide-modified MDI with an isocyanate content of 28%. A method for preparing a high-resilience polyurethane insole material includes the following steps: S1. Clean the mold cavity of the insole. Use an atomizing spray gun to spray the water-based release agent twice at a spraying pressure of 0.25MPa and a distance of 15cm from the surface of the mold cavity. After spraying, let it stand for 4 minutes to allow the release agent to form a film. Control the dry film thickness to 4μm. Preheat to 53℃ and keep warm for 35 minutes. S2. After preheating components A and B to 53℃ and holding for 35 minutes, they are mixed through a high-pressure mixing head and injected into the preheated mold cavity. The pressure of the high-pressure mixing head is 130 bar and the injection time is 4 seconds. After injection, the mold is closed and cured for 4.5 minutes. After demolding, it is transferred to a 65℃ drying tunnel for 38 minutes and then left to stand at room temperature for 20 hours to obtain a high-resilience polyurethane insole material.

[0049] Example 3 Block polyesters are prepared by the following methods: A1. The mass ratio of L-lactide, n-butanol, and zinc octanoate is controlled at 32:5:0.2. The L-lactide is obtained through the following pretreatment: L-lactide and anhydrous ethanol are mixed at a mass ratio of 1:10, stirred at 80°C and 300 rpm until completely dissolved, cooled to 5°C, and allowed to stand for crystallization for 2 hours. The mixture is then filtered using a 0.45 μm polytetrafluoroethylene filter membrane. The filter cake is washed three times with anhydrous ethanol at 5°C, and then subjected to a process at 50°C and a vacuum degree ≤-0.095 MPa. Dry under the conditions of a for 18 h; dry n-butanol with 4 Å molecular sieve for 24 h; dry zinc octanoate at 85 °C and vacuum degree ≤ -0.095 MPa for 2 h; under nitrogen protection, heat L-lactide to 130 °C to completely melt, add n-butanol and zinc octanoate at 250 rpm, and after the addition is complete, stir the reaction at 130 °C and 250 rpm for 2.5 h. After the reaction is completed, cool down to 120 °C to obtain hydroxyl-terminated polylactic acid; A2. The mass ratio of terminal hydroxyl polylactic acid (PLA) to ε-caprolactone (ε-caprolactone) is controlled at 1:2.2. The ε-caprolactone is obtained through the following pretreatment: 0.04 wt% hydroquinone is added to ε-caprolactone, and the mixture is distilled under reduced pressure at an absolute pressure of 18 mmHg and a distillation temperature of 135 °C. The distillate is collected and dried using a 4 Å molecular sieve for 28 h. ε-caprolactone is then added to the terminal hydroxyl polylactic acid at a speed of 250 rpm, with the addition time controlled at 20 min. After the addition is complete, the temperature is raised to 13 °C. The reaction was continued at 0℃ for 5 hours. After the reaction was completed, the mixture was cooled to room temperature, and dichloromethane was added until the solid content was 15wt%. The mixture was stirred for 15 minutes until completely dissolved. The solution was poured into methanol at 4℃ in a volume 10 times that of dichloromethane to precipitate the precipitate. The precipitate was filtered using a polytetrafluoroethylene filter membrane with a pore size of 0.45μm. The precipitate was washed three times with methanol at 4℃ (each time the amount of methanol was twice the volume of the precipitate). The precipitate was dried to constant weight at a temperature of 45℃ and a vacuum degree ≤-0.095MPa to obtain the block polyester. The modified prepolymer was prepared by the following method: B1. The mass ratio of polymer polyol, castor oil-modified polyol, block polyester, 1,4-butanediol and dibutyltin dilaurate is controlled at 90:6:10:12:0.06. Under nitrogen protection, the polymer polyol, castor oil-modified polyol, block polyester and 1,4-butanediol are mixed and dehydrated for 1.5 h at 115℃ and vacuum degree ≤-0.095MPa. The mixture is then cooled to 75℃, dibutyltin dilaurate is added, and the mixture is stirred for 10 min at 75℃ and 500 rpm to obtain a polyol mixture. B2. The mass ratio of carbodiimide-modified MDI, polyol mixture, and hydroquinone monomethyl ether was controlled at 30:112:0.03. Carbodiimide-modified MDI was added to the polyol mixture at 400 rpm, and the dropping time was controlled at 70 min. After the dropping was completed, the mixture was stirred at 80 °C for 3 h. Hydroquinone monomethyl ether was then added, and stirring was continued for 10 min. The mixture was then cooled to room temperature to obtain the modified prepolymer. The ADH dispersion was prepared by the following method: C1. The mass ratio of polyether polyol 330N, adipic acid dihydrazide and nano silica was controlled at 65:32:3. Polyether polyol 330N was dehydrated for 0.8 h at 90 °C and vacuum degree ≤ -0.09 MPa. Then adipic acid dihydrazide and nano silica were added. The mixture was sheared and emulsified for 15 min at 45 °C and 3000 rpm to obtain a suspension. C2. Control the mass ratio of isophorone diisocyanate to suspension to be 6:97. Add isophorone diisocyanate to suspension at room temperature and 600 rpm. Control the dropping time to be 45 min. After the dropping is completed, continue stirring and reacting at room temperature for 2 h. After the reaction is completed, degas for 10 min at 35℃ and vacuum degree ≤-0.090MPa to obtain ADH dispersion. The composite catalyst is composed of bismuth neodecanoate and dimethylaminoethyl ether in a mass ratio of 4.5:3; Component A comprises the following raw materials in parts by weight: 35 parts of polyether polyol EP-330NG, 30 parts of polytetrahydrofuran ether diol, 25 parts of modified prepolymer, 12 parts of ADH dispersion, 6 parts of 1,4-butanediol, 4 parts of cyclopentane, 1 part of polyether modified silicone oil, 0.7 parts of composite catalyst, and 0.8 parts of deionized water. Component A is prepared by the following method: Polyether polyol EP-330NG, polytetrahydrofuran ether diol, and 1,4-butanediol were mixed and dehydrated under vacuum. Then, under nitrogen protection, at a temperature of 35°C and a rotation speed of 800 rpm, modified prepolymer, ADH dispersion, deionized water, polyether modified silicone oil, cyclopentane, and composite catalyst were added sequentially. After each component was added, the mixture was stirred for 5 minutes. After all components were added, the mixture was stirred for another 15 minutes at a rotation speed of 1000 rpm. The mixture was then degassed for 10 minutes at a temperature of 35°C and a vacuum degree of ≤-0.090 MPa to obtain component A. A high-resilience polyurethane insole material, comprising component A and component B; wherein the mass ratio of component A to component B is 100:95; Component B is carbodiimide-modified MDI with an isocyanate content of 28%. A method for preparing a high-resilience polyurethane insole material includes the following steps: S1. Clean the mold cavity of the insole. Use an atomizing spray gun to spray the water-based release agent twice at a spraying pressure of 0.30MPa and a distance of 20cm from the surface of the mold cavity. After spraying, let it stand for 5 minutes to allow the release agent to form a film. Control the dry film thickness to 5μm. Preheat to 55℃ and keep warm for 30 minutes. S2. After preheating components A and B to 55°C and holding them at that temperature for 30 minutes, they are mixed through a high-pressure mixing head and then injected into the preheated mold cavity. The pressure of the high-pressure mixing head is 135 bar and the injection time is 3.5 seconds. After injection, the mold is closed and cured for 4 minutes. After demolding, the mold is transferred to a 70°C drying tunnel for 35 minutes and then left to stand at room temperature for 24 hours to obtain a high-resilience polyurethane insole material.

[0050] To verify the comprehensive performance of the high-resilience polyurethane insole materials prepared in Examples 1-3 of the present invention, the inventors set up Comparative Examples 1-6, as follows: Comparative Example 1 The difference between this comparative example and Example 1 is that, in the preparation of block polyester, n-butanol was replaced by 1,4-butanediol in equal mass, while the remaining steps and raw materials were the same as in Example 1. Block polyesters are prepared by the following methods: A1. The mass ratio of L-lactide, 1,4-butanediol, and zinc octanoate is controlled at 28:4:0.16. The L-lactide is obtained through the following pretreatment: L-lactide and anhydrous ethanol are mixed at a mass ratio of 1:10, stirred at 75°C and 200 rpm until completely dissolved, cooled to 0°C, and allowed to crystallize for 1 hour. The mixture is then filtered using a 0.45 μm polytetrafluoroethylene filter membrane. The filter cake is washed twice with anhydrous ethanol at 0°C and dried for 24 hours at 40°C and a vacuum degree ≤-0.095 MPa. 1,4-Butanediol is then... The 1,4-butanediol and zinc octanoate were pretreated as follows: 1,4-butanediol was dried using a 4Å molecular sieve for 20 hours; zinc octanoate was dried at 80°C and a vacuum of ≤-0.095MPa for 3 hours; L-lactide was heated to 125°C and completely melted under nitrogen protection, and 1,4-butanediol and zinc octanoate were added at 180 rpm. After the addition was complete, the mixture was stirred at 125°C and 180 rpm for 3.5 hours. After the reaction was completed, the temperature was lowered to 118°C to obtain hydroxyl-terminated polylactic acid. A2. The mass ratio of terminal hydroxyl polylactic acid (PLA) to ε-caprolactone is controlled at 1:1.9. The ε-caprolactone is obtained through the following pretreatment: 0.02 wt% hydroquinone is added to ε-caprolactone, and vacuum distillation is carried out under a pressure of 12 mmHg and a distillation temperature of 125 °C. The fraction is collected and dried with a 4 Å molecular sieve for 24 h. ε-caprolactone is added to terminal hydroxyl polylactic acid at a speed of 180 rpm, and the addition time is controlled at 30 min. After the addition is completed, the temperature is raised to 125 °C. The reaction was continued at ℃ for 6 hours. After the reaction was completed, it was cooled to room temperature, and dichloromethane was added until the solid content was 10 wt%. The mixture was stirred for 20 minutes until completely dissolved. The solution was poured into methanol at 0℃ in a volume 5 times that of dichloromethane to precipitate the precipitate. The precipitate was filtered using a polytetrafluoroethylene filter membrane with a pore size of 0.45 μm. The precipitate was washed twice with methanol at 0℃ (each time the amount of methanol was 1.5 times the volume of the precipitate). The precipitate was dried to constant weight at a temperature of 40℃ and a vacuum degree ≤ -0.095 MPa to obtain the block polyester.

[0051] Comparative Example 2 The difference between this comparative example and Example 1 is that in the original step B1, the block polyester was replaced with polycaprolactone diol by mass, while the remaining steps and raw materials were the same as in Example 1. B1. Controlling the mass ratio of polymeric polyol, castor oil-modified polyol, polycaprolactone diol, 1,4-butanediol, and dibutyltin dilaurate to 80:4:10:10:0.04, under nitrogen protection, the polymeric polyol, castor oil-modified polyol, polycaprolactone diol, and 1,4-butanediol are mixed and dehydrated for 2.5 h at 105℃ and a vacuum degree ≤-0.095MPa. After cooling to 70℃, dibutyltin dilaurate is added, and the mixture is stirred for 20 min at 70℃ and 300 rpm to obtain a polyol mixture.

[0052] Comparative Example 3 The difference between this comparative example and Example 1 is that nano-silica is not added in the original step C1, while the remaining steps and raw materials are the same as in Example 1. C1. Control the mass ratio of polyether polyol 330N and adipic acid dihydrazide to 65:28. After dehydrating polyether polyol 330N at 80℃ and vacuum degree ≤-0.09MPa for 1.2h, add adipic acid dihydrazide and shear emulsify at 35℃ and rotation speed 2000rpm for 25min to obtain a suspension.

[0053] Comparative Example 4 The difference between this comparative example and Example 1 is that step C2 is omitted when preparing the ADH dispersion, while the remaining steps and raw materials are the same as in Example 1. The ADH dispersion was prepared by the following method: The mass ratio of polyether polyol 330N, adipic acid dihydrazide, and nano silica was controlled at 65:28:2. Polyether polyol 330N was dehydrated for 1.2 h at 80 °C and vacuum degree ≤ -0.09 MPa. Then, adipic acid dihydrazide and nano silica were added, and the mixture was sheared and emulsified for 25 min at 35 °C and 2000 rpm to obtain a suspension. The suspension was then degassed for 20 min at 25 °C and vacuum degree ≤ -0.090 MPa to obtain an ADH dispersion.

[0054] Comparative Example 5 The difference between this comparative example and Example 1 is that the composite catalyst is replaced with bismuth neodecanoate by the same mass, while the other steps and raw materials are the same as in Example 1. Component A comprises the following raw materials in parts by weight: 30 parts of polyether polyol EP-330NG, 20 parts of polytetrahydrofuran ether diol, 20 parts of modified prepolymer, 10 parts of ADH dispersion, 4 parts of 1,4-butanediol, 3 parts of cyclopentane, 0.8 parts of polyether modified silicone oil, 0.5 parts of bismuth neodecanoate, and 0.6 parts of deionized water; Component A is prepared by the following method: Polyether polyol EP-330NG, polytetrahydrofuran ether diol, and 1,4-butanediol were mixed and dehydrated under vacuum. Then, under nitrogen protection, at a temperature of 25°C and a rotation speed of 500 rpm, modified prepolymer, ADH dispersion, deionized water, polyether modified silicone oil, cyclopentane, and bismuth neodecanoate were added sequentially. After each component was added, the mixture was stirred for 5 minutes. After all components were added, the mixture was stirred for another 25 minutes at a rotation speed of 800 rpm. The mixture was then degassed for 20 minutes at a temperature of 25°C and a vacuum degree of ≤-0.090 MPa to obtain component A.

[0055] Comparative Example 6 The difference between this comparative example and Example 1 is that the composite catalyst is replaced by an equal mass of dimethylaminoethyl ether, while the remaining steps and raw materials are the same as in Example 1. Component A comprises the following raw materials in parts by weight: 30 parts of polyether polyol EP-330NG, 20 parts of polytetrahydrofuran ether diol, 20 parts of modified prepolymer, 10 parts of ADH dispersion, 4 parts of 1,4-butanediol, 3 parts of cyclopentane, 0.8 parts of polyether modified silicone oil, 0.5 parts of dimethylaminoethyl ether, and 0.6 parts of deionized water; Component A is prepared by the following method: Polyether polyol EP-330NG, polytetrahydrofuran ether diol, and 1,4-butanediol were mixed and dehydrated under vacuum. Then, under nitrogen protection, at a temperature of 25°C and a rotation speed of 500 rpm, modified prepolymer, ADH dispersion, deionized water, polyether modified silicone oil, cyclopentane, and dimethylaminoethyl ether were added sequentially. After each component was added, the mixture was stirred for 5 min. After all components were added, the mixture was stirred for another 25 min at a rotation speed of 800 rpm. The mixture was then degassed for 20 min at a temperature of 25°C and a vacuum degree of ≤-0.090 MPa to obtain component A.

[0056] Performance testing The comprehensive performance of the high-resilience polyurethane insole materials prepared in Examples 1-3 and Comparative Examples 1-6 of this invention was tested respectively.

[0057] 1. Apparent density The apparent density of foamed plastics and rubber was determined according to the standard GB / T 6343-2009 "Determination of Apparent Density". The high-resilience polyurethane insole materials prepared in Examples 1-3 and Comparative Examples 1-6 were cut into samples with a size of 100mm×100mm×50mm. After conditioning in an environment of 23±2℃ and 50±5% RH for 16h, the mass was weighed using an electronic balance with an accuracy of 0.01g. The apparent density (unit: g / cm³) was calculated according to the formula ρ=m / V. The result was taken as the arithmetic mean of 3 parallel samples.

[0058] 2. Rebound performance (rebound rate) The test was conducted in accordance with the standard GB / T 6670-2008 "Determination of Rebound Performance of Flexible Foam Polymer Materials by Falling Ball Method". The rebound rate of the material was determined by the falling ball method. The sample was cut from a flat area with a thickness of 50 mm. Before the test, the sample surface was lightly sanded with fine sandpaper to ensure flatness. In an environment of 23±2℃, a steel ball with a diameter of 16±0.1 mm was dropped freely from a height of 500±1 mm. The rebound height was recorded. The rebound rate (%) was calculated according to the formula (rebound height / drop height)×100%. Five different positions (spaced ≥20 mm) were selected on the sample surface, and each position was tested once. The arithmetic mean of the five data points was taken as the final result.

[0059] 3. Hardness The test was conducted in accordance with the standard GB / T 531.1-2008 "Test Method for Indentation Hardness of Vulcanized Rubber or Thermoplastic Rubber - Part 1: Shore Hardness Tester Method (Shore Hardness)". The sample thickness was 6 mm and the surface was flat and free of bubbles. The sample was indented at a speed of 3.2 ± 0.2 mm / s using a Shore A hardness tester at an environment of 23 ± 2℃. The hardness value was read 15 seconds after the indenter contacted the sample. Five points were tested at different positions on the sample (interval ≥ 15 mm), and the arithmetic mean was taken as the final hardness result. The unit is Shore A.

[0060] 4. Compression permanent deformation The test was conducted in accordance with the standard GB / T 6669-2008 "Determination of Compression Permanent Deformation of Flexible Foam Polymer Materials". A cylindrical sample with a diameter of 29±0.5mm and a diameter of 12.5±0.5mm was cut. After conditioning the sample at 23±2℃ and 50±5% RH for 16 hours, the compression device was preheated to 70℃ and placed in an oven at 70℃ with a compression rate of 50% for 22 hours. After removal, the limiting plate was immediately removed, and the sample was allowed to recover at 23±2℃ for 30 minutes. The height after recovery was measured, and the result was the average of 3 samples.

[0061] 5. Tensile strength and elongation at break The test was conducted according to the standard GB / T 6344-2008 "Determination of Tensile Strength and Elongation at Break of Flexible Foam Polymer Materials". The insole was placed flat on the workbench (the bottom of the insole was in contact with the workbench surface). Type IV dumbbell-shaped specimens (total length 115 mm, gauge length width 6.0 ± 0.1 mm, thickness as measured) were cut perpendicular to the workbench surface. The original cross-sectional area A0 = width × thickness (mm²). After conditioning at 23 ± 2℃ and 50 ± 5% RH for 16 h, the test was conducted at a tensile speed of 500 ± 50 mm / min. The formula for tensile strength (MPa) is σ = Fmax / A0, where Fmax is the maximum load in N; A0 is the original cross-sectional area in mm². The formula for elongation at break (%) is ε = [(L - L0) / L0] × 100%, where L0 is the original gauge length (25 mm) in mm; L is the gauge length at break in mm. The result is the arithmetic mean of 5 valid specimens.

[0062] 6. Tear strength The test was conducted in accordance with the standard GB / T 10808-2006 "Determination of Tear Strength of Porous Polymer Elastic Materials". The insole was placed flat on the workbench (with the bottom of the insole in contact with the workbench surface). A right-angled (Type C) specimen was cut along the direction perpendicular to the workbench surface. After conditioning at 23±2℃ and 50±5% RH for 16 hours, the test was conducted at a tensile speed of 500±50 mm / min. The tear strength (N / mm) formula is τ=Fmax / d, where Fmax is the maximum load in N; d is the specimen thickness in mm. During the cutting process, the blade should be used to avoid damaging the edge of the specimen. The result is the arithmetic mean of 5 valid specimens.

[0063] The specific test results are shown in Table 1.

[0064] Table 1: Comprehensive Performance Data of High-Resilience Polyurethane Insole Materials

[0065] As shown in Table 1, the high-resilience polyurethane insole materials prepared in Examples 1-3 of this invention are significantly superior to those in Comparative Examples 1-6 in terms of resilience, compression set, and mechanical properties.

[0066] In Comparative Example 1, replacing n-butanol in the mixed initiator with 1,4-butanediol resulted in increased functionality of the block polyester, excessive crosslinking density of the molecular chain, stress concentration inside the material, decreased resilience, significantly increased compression set, and decreased tear strength.

[0067] Comparative Example 2 replaced the block polyester with polycaprolactone diol, which disrupted the microphase separation structure induced by the hard segments of PLA, resulting in a decrease in the material's resilience, structural stability, and overall mechanical properties.

[0068] In Comparative Example 3, no nano-silica was added during the preparation of the ADH dispersion. The integrity of the ADH coating layer structure was damaged, and the cross-linking network was not dense enough after curing, resulting in increased compression set and decreased tear strength.

[0069] In Comparative Example 4, step C2 was omitted during the preparation of the ADH dispersion, i.e., the coating treatment of adipate dihydrazide with isophorone diisocyanate was not used. As a result, the ADH reacted prematurely at room temperature, and the crosslinking reaction was insufficient during the curing process, leading to a decrease in resilience and dimensional stability.

[0070] Comparative Examples 5 and 6 used a single bismuth neodecanoate or a single dimethylaminoethyl ether to replace the composite catalyst, respectively. The former resulted in foaming kinetic imbalance, leading to coarsening of the cells and a decrease in resilience; the latter resulted in excessively rapid gelation, causing localized bursting and a decrease in mechanical properties.

[0071] This specific embodiment is merely an explanation of the present invention and is not intended to limit the invention. After reading this specification, those skilled in the art can make modifications to this embodiment without contributing any inventive step, but such modifications are protected by patent law as long as they are within the scope of the claims of the present invention.

Claims

1. A high-resilience polyurethane insole material, characterized in that, It includes component A and component B; the mass ratio of component A to component B is 100:90-95; Component A comprises the following raw materials in parts by weight: 30-35 parts of polyether polyol EP-330NG, 20-30 parts of polytetrahydrofuran ether diol, 20-25 parts of modified prepolymer, 10-12 parts of ADH dispersion, 4-6 parts of 1,4-butanediol, 3-4 parts of cyclopentane, 0.8-1 part of polyether modified silicone oil, 0.5-0.7 parts of composite catalyst, and 0.6-0.8 parts of deionized water; The modified prepolymer is prepared by chain extension of polymer polyol, castor oil-modified polyol and block polyester via carbodiimide-modified MDI; The composite catalyst is composed of bismuth neodecanoate and dimethylaminoethyl ether in a mass ratio of 3.5-4.5:3; Component B is carbodiimide-modified MDI with an isocyanate content of 28-30%.

2. The high-resilience polyurethane insole material according to claim 1, characterized in that, The block polyester is prepared by the following method: A1. Under nitrogen protection, L-lactide is heated to 125-130℃ and completely melted. n-Butanol and zinc octanoate are added while stirring. After the addition is complete, the mixture is stirred to react. After the reaction is complete, the temperature is lowered to 115-120℃ to obtain hydroxyl-terminated polylactic acid. A2. Under stirring, ε-caprolactone is added to terminal hydroxyl polylactic acid. After the addition is complete, the temperature is raised to 125-130℃ and the reaction is stirred for 5-6 hours. After the reaction is completed, the mixture is cooled to room temperature, dichloromethane is added, and the mixture is stirred until completely dissolved. The solution is then poured into methanol to precipitate the precipitate. After filtration, washing, and drying, block polyester is obtained.

3. The high-resilience polyurethane insole material according to claim 2, characterized in that, In step A1, the mass ratio of L-lactide, n-butanol, and zinc octanoate is 28-32:4-5:0.16-0.

2.

4. The high-resilience polyurethane insole material according to claim 2, characterized in that, In step A2, the mass ratio of terminal hydroxyl polylactic acid to ε-caprolactone is 1:1.9-2.

2.

5. The high-resilience polyurethane insole material according to claim 1, characterized in that, The modified prepolymer is prepared by the following method: B1. Under nitrogen protection, the polymer polyol, castor oil modified polyol, block polyester and 1,4-butanediol are mixed, vacuum dehydrated, cooled to 70-75℃, dibutyltin dilaurate is added, and stirred evenly to obtain a polyol mixture. B2. Under stirring, carbodiimide-modified MDI is added to the polyol mixture. After the addition is complete, the mixture is stirred at 78-80℃ for 3-4 hours. Hydroquinone monomethyl ether is then added, and stirring is continued for 10-15 minutes. The mixture is then cooled to room temperature to obtain the modified prepolymer.

6. The high-resilience polyurethane insole material according to claim 5, characterized in that, In step B1, the mass ratio of polymeric polyol, castor oil-modified polyol, block polyester, 1,4-butanediol and dibutyltin dilaurate is 80-90:4-6:10:10-12:0.04-0.

06.

7. The high-resilience polyurethane insole material according to claim 5, characterized in that, In step B2, the mass ratio of carbodiimide-modified MDI, polyol mixture, and hydroquinone monomethyl ether is 30:110-112:0.015-0.

03.

8. The high-resilience polyurethane insole material according to claim 1, characterized in that, The ADH dispersion was prepared by the following method: C1. After vacuum dehydration of polyether polyol 330N, adipic acid dihydrazide and nano silica are added, followed by shear emulsification to obtain a suspension. C2. Under stirring, isophorone diisocyanate is added to the suspension. After the addition is complete, the mixture is stirred at room temperature for 2-3 hours. After the reaction is complete, the mixture is degassed under vacuum to obtain an ADH dispersion.

9. The high-resilience polyurethane insole material according to claim 1, characterized in that, Component A is prepared by the following method: Polyether polyol EP-330NG, polytetrahydrofuran ether diol, and 1,4-butanediol were mixed and dehydrated under vacuum. Then, under nitrogen protection and stirring, modified prepolymer, ADH dispersion, deionized water, polyether modified silicone oil, cyclopentane, and composite catalyst were added sequentially. The mixture was stirred until homogeneous and then degassed under vacuum to obtain component A.

10. A method for preparing a high-resilience polyurethane insole material according to any one of claims 1-9, characterized in that, Includes the following steps: S1. Clean the cavity of the insole mold, spray with water-based release agent, preheat to 50-55℃ and keep warm for 30-40 minutes; S2. After preheating components A and B to 50-55℃ and holding them at that temperature for 30-40 minutes, inject them into the mold through a high-pressure mixing head, close the mold and cure for 4-5 minutes, demold and transfer to a drying tunnel at 60-70℃ for 35-40 minutes, and then let it stand at room temperature for 16-24 hours to obtain a high-resilience polyurethane insole material.

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