A shoe material composition and foamed shoe material based on a biomass raw material

Abstract

The application relates to the technical field of foaming materials, and particularly provides a shoe material composition based on a biomass raw material and a foaming shoe material. The foaming shoe material composition based on the biomass raw material comprises, according to 100% by weight of raw material components: 0-45% of bio-based TPAE, 0-45% of bio-based TPU, 20-37% of bio-based EVA, 22-35% of bio-based POE and 5-15% of a compatilizer; the sum of the weight percentages of the bio-based TPAE and the bio-based TPU is 30-45%; and the compatilizer is a combination of C12-C36 alkyl-terminated polyester-based polyurethane and C12-C36 alkyl-terminated alkyl polyurethane at a weight ratio of 1:9-9:1. The shoe material composition has good foaming performance, and the foaming shoe material has high resilience and good mechanical properties.

Description

Technical Field

[0001] This application relates to the field of foamed material technology, specifically to a shoe material composition based on biomass raw materials and a foamed shoe material. Background Technology

[0002] Environmental protection is a major trend in the development of footwear materials. Besides advancements in technology, such as supercritical fluid foaming, there's also advancement in materials, such as the use of biomass raw materials. Biomass raw materials refer to a new type of material prepared using renewable biomass, including crops, trees, other plants, and their residues and contents, through biological, chemical, and physical methods. Using biomass raw materials can reduce the use of petroleum-based raw materials and avoid the environmental damage caused by petroleum-based raw materials during production and use.

[0003] Polymer materials used in shoe materials include ethylene vinyl acetate copolymer (EVA), thermoplastic polyurethane elastomer (TPU), thermoplastic polyamide elastomer (TPAE), polyolefin elastomer (POE), and ethylene propylene diene monomer (EPDM), all of which have corresponding biomass polymers.

[0004] However, directly replacing the original petroleum-based raw materials with biomass raw materials results in differences in molding and product performance, especially for foamed shoe materials prepared using supercritical fluid foaming technology. The foaming capacity and performance of the foamed shoe materials are inferior to those using petroleum-based raw materials. For example, Chinese invention patent application CN115340721A discloses a shoe material containing bio-based EVA, suitable for supercritical fluid foaming technology. By weight, it includes 70-75 parts of bio-based ethylene vinyl acetate copolymer, 8-15 parts of vinyl ester copolymer, 8-18 parts of ethylene octene copolymer, 3-10 parts of styrene-butadiene block copolymer, 3-10 parts of styrene elastomer, 3-10 parts of nano-grade talc, 1-3 parts of peroxide, and 1.2-1.6 parts of nucleating agent. However, this method uses a large amount of non-bio-based raw materials, resulting in an insufficient bio-based content in the shoe material. Summary of the Invention

[0005] In order to solve the technical problems of low biomass content and poor foaming performance of existing foamed shoe materials, this application provides a shoe material composition and foamed shoe material based on biomass raw materials.

[0006] The technical solution adopted in this application is as follows:

[0007] A foamed shoe material composition based on biomass raw materials, wherein the raw material components, by 100% weight, comprise: 0-45% bio-based TPAE, 0-45% bio-based TPU, 20-37% bio-based EVA, 22-35% bio-based POE, and 5-15% compatibilizer;

[0008] The sum of the weight percentages of the bio-based TPAE and the bio-based TPU is 30-45%.

[0009] The compatibilizer is a combination of C12-C36 alkyl-terminated polyester polyurethane and C12-C36 alkyl-terminated alkyl polyurethane in a weight ratio of 1:9 to 9:1.

[0010] Preferably, the C12-C36 alkyl-terminated polyester polyurethane is prepared by the following method: a polyester polyurethane prepolymer is reacted with a polymer of the general formula C... n H 2n+1 R 1 The first compound is based on the NCO group and R 1 The reaction is carried out with a molar ratio of groups of 1:1 to 3 to obtain the product, wherein R is... 1 It is a hydroxyl, primary amino, or secondary amino group, with n = 12–36.

[0011] Preferably, the C12-C36 alkyl-terminated alkyl polyurethane is prepared by the following method: alkyl polyurethane prepolymer is reacted with a polymer of the general formula C... m H 2m+1 R 2 The second compound is based on the NCO group and R 2 The reaction is carried out with a molar ratio of groups of 1:1 to 3 to obtain the product, wherein R is... 2 It is a hydroxyl, primary amino, or secondary amino group, with m = 12–36.

[0012] More preferably, the weight content of NCO groups in the polyester-based polyurethane prepolymer and the alkyl polyurethane prepolymer is 2-8%, respectively.

[0013] More preferably, the average molecular weight of the polyester diol used in the polyester-based polyurethane prepolymer is 300 to 1500.

[0014] More preferably, the alkyl diol used in the alkyl polyurethane prepolymer is a C12-C24 alkyl diol.

[0015] Preferably, the raw material components further include one or more of the following: 0.5-3% peroxide vulcanizing agent, 0.5-1.5% nucleating agent, and 0.5-2% pigment.

[0016] More preferably, the peroxide sulfide is selected from one or more combinations of dicumyl peroxide, di-tert-butyl peroxide, benzoyl peroxide and bis(2,5-diphenyl) sulfide.

[0017] More preferably, the nucleating agent is selected from one or a combination of several of nano-silica, nano-calcium carbonate, nano-titanium dioxide, nano-zinc oxide, nano-kaolin, nano-montmorillonite, and nano-attapulgite.

[0018] A foamed shoe material, prepared by the following method:

[0019] The raw material components in the foamed shoe material composition of any of the above technical solutions are mixed and added to a screw extruder for extrusion granulation, then shaped in a mold, and foamed using supercritical fluid foaming technology.

[0020] Alternatively, the raw material components other than the peroxide vulcanizing agent in the foamed shoe material composition of any of the above technical solutions are mixed and added to a screw extruder for extrusion granulation to obtain initial particles; the initial particles are mixed and kneaded evenly with the peroxide vulcanizing agent, then vulcanized in a mold, and foamed using supercritical fluid foaming technology.

[0021] In summary, this application has the following beneficial effects:

[0022] 1. This application uses three to four bio-based polymer materials—TPAE and / or TPU, POE, and EVA—to create a foamed shoe material that combines the performance characteristics of these polymer materials. However, these polymer materials have significant differences in polarity, making it difficult to achieve good compatibility. TPAE and TPU have high polarity, EVA has medium polarity, and POE has low polarity. This application uses two polyurethanes with different structures as compatibilizers, achieving good compatibility among the polymer materials and maximizing their performance. It also solves the problems of poor foaming ability and poor performance of the foamed shoe material caused by using bio-based polymer materials.

[0023] 2. This application addresses the issue of significant differences in polarity among the various polymer materials used, finding that a single-component compatibilizer is insufficient to achieve good compatibility. This application employs a combination of two polyurethanes with different structures as the compatibilizer. These two polyurethanes have different polarities, and their combination achieves good compatibility with the bio-based polymer materials used. Detailed Implementation

[0024] To make the objectives, technical solutions, and advantages of this invention clearer, the technical solutions of this invention will be described in detail below.

[0025] Throughout this specification, unless otherwise specified, the terminology used herein should be understood as having the meaning commonly used in the art. Therefore, unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains. In the event of any conflict, this specification shall prevail.

[0026] On the one hand, this application proposes a foamed shoe material composition based on biomass raw materials, wherein the raw material components, by 100% weight, include: 0-45% bio-based TPAE, 0-45% bio-based TPU, 20-37% bio-based EVA, 22-35% bio-based POE and 5-15% compatibilizer;

[0027] The combined weight percentage of bio-based TPAE and bio-based TPU is 30-45%.

[0028] The compatibilizer is a combination of C12-C36 alkyl-terminated polyester polyurethane and C12-C36 alkyl-terminated alkyl polyurethane in a weight ratio of 1:9 to 9:1.

[0029] In this application, the bio-based polymer raw material components, including TPAE, TPU, EVA, and POE, each possess unique performance characteristics. Their combined use allows each component to demonstrate its specific properties, resulting in a better overall performance of the foamed shoe material. However, TPAE and TPU have high polarity, EVA has moderate polarity, and POE has low polarity. Consequently, the compatibility of these polymer raw materials is poor, making it difficult to achieve good compatibility when mixed, which affects the foaming capacity and performance of the foamed shoe material. To address these technical problems, this application employs two polyurethanes with different structures as compatibilizers. These two polyurethanes have varying polarities, and their combination provides good compatibility with the various polymer raw materials. Furthermore, because the compatibilizer has a lower molecular weight compared to the bio-based polymers, it can be used as a plasticizer, reducing the hardness of the foamed shoe material composition and improving the foaming capacity and performance of the foamed shoe material.

[0030] In this application, bio-based TPAE, bio-based TPU, bio-based EVA, and bio-based POE can all be obtained directly from the market.

[0031] Furthermore, in this application, the weight ratio of C12-C36 alkyl-terminated polyester polyurethane to C12-C36 alkyl-terminated alkyl polyurethane can be 3:7 to 7:3. For example, the weight ratio can be any value among 3:7, 4:6, 5:5, 6:4, 7:3, etc., but is not limited to those listed above.

[0032] In a preferred embodiment of this application, C12-C36 alkyl-terminated polyester polyurethane is prepared by the following method: A polyester polyurethane prepolymer is reacted with a general formula C... n H 2n+1 R 1 The first compound is based on the NCO group and R 1 The reaction is carried out with a molar ratio of groups of 1:1 to 3 to obtain the product, wherein R is... 1 The end groups are hydroxyl, primary amino, or secondary amino groups, with n = 12–36. Polyester-based polyurethane prepolymers have NCO groups at the end, which can react with R... 1The functional groups undergo addition reactions. For example, the NCO group in a polyester-based polyurethane prepolymer and the R group in the first compound... 1 The molar ratio of the groups can be any value from 1:1, 1:1.2, 1:1.5, 1:1.8, 1:2, 1:2.2, 1:2.5, 1:2.8, 1:3, etc., but is not limited to those listed above. When the first compound is in excess, the excess first compound can be removed by vacuum distillation or thin-film evaporation. For example, the first compound can be 1-dodecyl alcohol, 1-octadecyl alcohol, 1-octadecylamine, didodecylamine, 1-tetracosylamine, etc., but is not limited to those listed above.

[0033] Specifically, polyester-based polyurethane prepolymers can be prepared as follows: polyester diol and diisocyanate monomers are added to a reaction vessel at a molar ratio of 0.55 to 0.85:1, and reacted at room temperature to 100°C for 2 to 10 hours to obtain the product.

[0034] In a preferred embodiment of this application, C12-C36 alkyl-terminated alkyl polyurethane is prepared by the following method: alkyl polyurethane prepolymer is reacted with a general formula C... m H 2m+1 R 2 The second compound is based on the NCO group and R 2 The reaction is carried out with a molar ratio of groups of 1:1 to 3 to obtain the product, wherein R is... 2 The amino group is hydroxyl, primary amino, or secondary amino, with m = 12–36. The end groups of alkyl polyurethane prepolymers are NCO groups, which can react with R... 2 The groups undergo addition reactions. For example, the NCO group in alkyl polyurethane prepolymers and the R group in the second compound. 2 The molar ratio of the groups can be any value from 1:1, 1:1.2, 1:1.5, 1:1.8, 1:2, 1:2.2, 1:2.5, 1:2.8, 1:3, etc., but is not limited to those listed above. When the second compound is in excess, the excess second compound can be removed by means of vacuum distillation or the like. For example, the second compound can be 1-dodecyl alcohol, 1-octadecyl alcohol, 1-octadecylamine, didodecylamine, 1-tetracosylamine, etc., but is not limited to those listed above.

[0035] Specifically, alkyl polyurethane prepolymers can be prepared as follows: alkyl diols and diisocyanate monomers are added to a reaction vessel at a molar ratio of 0.55 to 0.9:1, and reacted at room temperature to 100°C for 2 to 10 hours to obtain the product.

[0036] In this application, there are no particular limitations on the diisocyanate monomers mentioned above, and they can be TDI, MDI, HMDI, IPDI, etc.

[0037] In a more preferred embodiment of this application, the weight content of NCO groups in the polyester-based polyurethane prepolymer and the alkyl polyurethane prepolymer is 2-8%, respectively. For example, the weight content of NCO groups can be any value among 2%, 2.5%, 3%, 3.5%, 4%, 4.5%, 5%, 5.5%, 6%, 6.5%, 7%, 7.5%, and 8%, but is not limited to those listed above.

[0038] In a more preferred embodiment of this application, the average molecular weight of the polyester diol used in the polyester-based polyurethane prepolymer is 300–1500. When the average molecular weight of the polyester diol is within the above range, the polarity of the obtained C12-C36 alkyl-terminated polyester-based polyurethane is more suitable. If the average molecular weight of the polyester diol is lower, the distribution density of urethane bonds is higher, and the polarity is relatively greater; conversely, if the average molecular weight of the polyester diol is higher, the distribution density of urethane bonds is lower, and the polarity is relatively lower.

[0039] In a more preferred embodiment of this application, the alkyl diol used in the alkyl polyurethane prepolymer is a C12-C24 alkyl diol. Since the polarity of the alkyl diol used is significantly lower than that of the polyester diol, the alkyl polyurethane prepolymer has lower polarity compared to the polyester-based polyurethane prepolymer. For example, the C12-C24 alkyl diol can be 1,12-dodecyl diol, 1,18-octadecyl diol, 1,12-octadecyl diol, 1,14-tetradecyl diol, 1,22-docosahexadecyl diol, etc., without particular limitation.

[0040] In a preferred embodiment of this application, the raw material components further include one or more combinations of 0.5–3% peroxide vulcanizing agent, 0.5–1.5% nucleating agent, and 0.5–2% pigment. The addition of peroxide vulcanizing agent to the raw material components of this application can vulcanize EVA and POE, thereby further improving the resilience, abrasion resistance, and other properties of the foamed shoe material. The addition of nucleating agent to the raw material components can promote the crystallization of hard segments in each raw material component, improving the mechanical strength, resilience, and abrasion resistance of the foamed shoe material.

[0041] In a more preferred embodiment of this application, the peroxide sulfiding agent is not particularly limited and can be selected from one or more combinations of dicumyl peroxide, di-tert-butyl peroxide, benzoyl peroxide and bis(2,5-diphenyl) sulfiding agent.

[0042] In a more preferred embodiment of this application, the nucleating agent is not particularly limited and can be selected from one or a combination of several of nano-silica, nano-calcium carbonate, nano-titanium dioxide, nano-zinc oxide, nano-kaolin, nano-montmorillonite, and nano-attapulgite.

[0043] On the other hand, this application proposes a foamed shoe material, the preparation method of which is as follows:

[0044] When the raw material components do not contain peroxide vulcanizing agents, the raw material components in the foamed shoe material composition of any of the above technical solutions are mixed and added to a screw extruder for extrusion granulation, then shaped in a mold, and foamed using supercritical fluid foaming technology.

[0045] When the raw material components contain peroxide vulcanizing agent, the other raw material components in the foamed shoe material composition of any of the above technical solutions, except for the peroxide vulcanizing agent, are mixed and added to a screw extruder for extrusion granulation to obtain primary granules; the primary granules are mixed and kneaded evenly with the peroxide vulcanizing agent, then vulcanized in a mold, and foamed using supercritical fluid foaming technology.

[0046] In this application, there are no particular limitations on the supercritical fluid foaming technology; supercritical CO2 foaming, supercritical N2 foaming, etc., can be used. One operating method is as follows: a semi-finished product formed in a mold is placed in a high-pressure reactor and sealed. Supercritical fluid is introduced and pressurized to saturation at a pressure of 8–30 MPa and a temperature of 40–65°C for a holding time of 12–36 hours. Then, the supercritical fluid is rapidly released to obtain a swollen material. The swollen material is then placed in a constant-temperature device for foaming to obtain foamed shoe material at a foaming temperature of 80–120°C and a foaming time of 0.1–5 minutes.

[0047] The technical solution of this application will be described in detail below with reference to preparation examples, embodiments, and comparative examples.

[0048] Preparation Example 1

[0049] The polyester diol is polyethylene terephthalate-1,4-cyclohexanediethanol ester with an average molecular weight of 1000.

[0050] Under nitrogen protection, polyester diol and IPDI were added to a reaction vessel at a molar ratio of 0.6:1, heated to 80°C, and stirred for 3 hours to obtain a polyurethane prepolymer. The NCO group content was measured to be 3.9%.

[0051] Under nitrogen protection, the above polyurethane prepolymer and 1-octadecyl alcohol were added to a reaction vessel at a molar ratio of NCO to OH of 1:2. Then, 0.25% by weight of dibutyltin dilaurate was added. The mixture was heated to 80°C and stirred for 2 hours. The pressure was reduced to below 100 Pa, and the temperature was raised to 190°C to remove unreacted 1-octadecyl alcohol, thus obtaining alkyl-terminated polyester polyurethane.

[0052] Preparation Example 2

[0053] The polyester diol is polyethylene terephthalate-1,4-cyclohexanediethanol ester with an average molecular weight of 1500.

[0054] Under nitrogen protection, polyester diol and HMDI were added to a reaction vessel at a molar ratio of 0.55:1, heated to 90°C, and stirred for 2 hours to obtain a polyurethane prepolymer. The NCO group content was measured to be 3.3%.

[0055] Under nitrogen protection, the above polyurethane prepolymer and 1-dodecyl alcohol were added to a reaction vessel at a molar ratio of NCO to OH of 1:1.2. Then, 0.22% by weight of dibutyltin dilaurate was added. The mixture was heated to 80°C and stirred for 2 hours. The pressure was reduced to below 100 Pa, and the mixture was heated to 140°C to remove unreacted 1-dodecyl alcohol, thus obtaining alkyl-terminated polyester polyurethane.

[0056] Preparation Example 3

[0057] Under nitrogen protection, 1,22-docodecyl diol and IPDI were added to a reaction vessel at a molar ratio of 0.65:1, the temperature was raised to 80°C, and the mixture was stirred for 2 hours to obtain a polyurethane prepolymer. The NCO group content was measured to be 6.5%.

[0058] Under nitrogen protection, the above polyurethane prepolymer and 1-tetradecyl alcohol were added to a reaction vessel at a molar ratio of NCO to OH of 1:1.5. Then, 0.2% by weight of dibutyltin dilaurate was added. The mixture was heated to 80°C and stirred for 2 hours. The pressure was reduced to below 100 Pa, and the temperature was raised to 150°C to remove unreacted 1-tetradecyl alcohol, thus obtaining alkyl-terminated alkyl polyurethane.

[0059] Preparation Example 4

[0060] Under nitrogen protection, 1,18-octadecyl diol and HMDI were added to a reaction vessel at a molar ratio of 0.75:1, the temperature was raised to 80°C, and the reaction was stirred for 2 hours to obtain a polyurethane prepolymer. The NCO group content was measured to be 4.2%.

[0061] Under nitrogen protection, the above polyurethane prepolymer and 1-tetracosyl alcohol were added to the reaction vessel at a molar ratio of NCO to OH of 1:1. Then, 0.2% by weight of dibutyltin dilaurate was added, the temperature was raised to 90°C, and the reaction was stirred for 2 hours to obtain alkyl-terminated alkyl polyurethane.

[0062] Example 1

[0063] The foamed shoe material composition comprises, by 100% by weight, 25% bio-based TPAE, 10% bio-based TPU, 31% bio-based EVA, 25% bio-based POE, and 9% compatibilizer.

[0064] The compatibilizer is composed of the alkyl-terminated polyester polyurethane of Preparation Example 1 and the alkyl-terminated alkyl polyurethane of Preparation Example 3 in a weight ratio of 5:5.

[0065] After the raw material components are mixed, they are added to a twin-screw extruder and extruded and granulated at 220-250°C. The granules are then molded into semi-finished products in a mold and foamed using supercritical CO2.

[0066] The supercritical CO2 foaming molding process is as follows: The semi-finished product is placed in a high-pressure reactor and sealed. Supercritical CO2 fluid is introduced and pressurized to saturation at a pressure of 22 MPa and a temperature of 60°C for 16 hours. Then, the supercritical fluid is rapidly released to obtain the swollen material. The swollen material is then placed in a constant temperature device for foaming to obtain foamed shoe material at a foaming temperature of 105°C and a foaming time of 1 minute.

[0067] Example 2

[0068] The difference between Example 2 and Example 1 is that the compatibilizer in Example 1 is replaced with an equal weight percentage of alkyl-terminated polyester polyurethane from Preparation Example 1 and alkyl-terminated alkyl polyurethane from Preparation Example 4 in a weight ratio of 5:5. The remaining steps remain unchanged.

[0069] Example 3

[0070] The difference between Example 3 and Example 1 is that the compatibilizer in Example 1 is replaced with an equal weight percentage of alkyl-terminated polyester polyurethane from Preparation Example 2 and alkyl-terminated alkyl polyurethane from Preparation Example 3 in a weight ratio of 5:5. The remaining steps remain unchanged.

[0071] Example 4

[0072] The difference between Example 4 and Example 1 is that the compatibilizer in Example 1 is replaced with an equal weight percentage of alkyl-terminated polyester polyurethane from Preparation Example 2 and alkyl-terminated alkyl polyurethane from Preparation Example 4 in a weight ratio of 5:5. The remaining steps remain unchanged.

[0073] Example 5

[0074] The difference between Example 5 and Example 1 is that the compatibilizer in Example 1 is replaced with an equal weight percentage of alkyl-terminated polyester polyurethane from Preparation Example 1 and alkyl-terminated alkyl polyurethane from Preparation Example 3 in a weight ratio of 9:1. The remaining steps remain unchanged.

[0075] Example 6

[0076] The difference between Example 6 and Example 1 is that the compatibilizer in Example 1 is replaced with an equal weight percentage of alkyl-terminated polyester polyurethane from Preparation Example 1 and alkyl-terminated alkyl polyurethane from Preparation Example 3 in a weight ratio of 7:3. The remaining steps remain unchanged.

[0077] Example 7

[0078] The difference between Example 7 and Example 1 is that the compatibilizer in Example 1 is replaced with an equal weight percentage of alkyl-terminated polyester polyurethane from Preparation Example 1 and alkyl-terminated alkyl polyurethane from Preparation Example 3 in a weight ratio of 3:7. The remaining steps remain unchanged.

[0079] Example 8

[0080] The difference between Example 8 and Example 1 is that the compatibilizer in Example 1 is replaced with an equal weight percentage of alkyl-terminated polyester polyurethane from Preparation Example 1 and alkyl-terminated alkyl polyurethane from Preparation Example 3 in a weight ratio of 1:9. The remaining steps remain unchanged.

[0081] Comparative Example 1

[0082] The difference between Comparative Example 1 and Example 1 is that no compatibilizer was added in Example 1. The remaining steps remained unchanged.

[0083] Comparative Example 2

[0084] The difference between Comparative Example 2 and Example 1 is that the compatibilizer in Example 1 was replaced with an equal weight percentage of the alkyl-terminated polyester polyurethane of Preparation Example 1. The remaining steps remained unchanged.

[0085] Comparative Example 3

[0086] The difference between Comparative Example 3 and Example 1 is that the compatibilizer in Example 1 was replaced with an equal weight percentage of the alkyl-terminated alkyl polyurethane used in Preparation Example 3. All other steps remained unchanged.

[0087] Example 9

[0088] The foamed shoe material composition comprises, by weight, 35% bio-based TPAE, 28% bio-based EVA, 28% bio-based POE, 8% compatibilizer and 1% nano-silica with an average particle size of 10 nm.

[0089] The compatibilizer is composed of the alkyl-terminated polyester polyurethane of Preparation Example 2 and the alkyl-terminated alkyl polyurethane of Preparation Example 3 in a weight ratio of 6:4.

[0090] The foamed shoe material was prepared according to the method in Example 1.

[0091] Example 10

[0092] The foamed shoe material composition comprises, by weight, 36% bio-based TPAE, 29% bio-based EVA, 29% bio-based POE, 5% compatibilizer from Example 9, and 1% nano-silica from Example 9.

[0093] The foamed shoe material was prepared according to the method in Example 1.

[0094] Example 11

[0095] The foamed shoe material composition comprises, by weight, 33% bio-based TPAE, 26% bio-based EVA, 26% bio-based POE, 14% compatibilizer from Example 9, and 1% nano-silica from Example 9.

[0096] The foamed shoe material was prepared according to the method in Example 1.

[0097] Example 12

[0098] The foamed shoe material composition comprises, by weight, 34.7% bio-based TPAE, 27.6% bio-based EVA, 27.7% bio-based POE, 8% compatibilizer, 1% cumene peroxide and 1% nano-silica with an average particle size of 10 nm.

[0099] All raw material components except cumene peroxide are mixed and added to a twin-screw extruder for extrusion granulation at 220-250°C. The granulated particles are then mixed evenly with cumene peroxide in a mixer, transferred to a mold for compression molding into a semi-finished product, and foamed using supercritical CO2 to obtain foamed shoe material.

[0100] The supercritical CO2 foaming molding process is as described in Example 1.

[0101] Comparative Example 4

[0102] The foamed shoe material composition comprises, by weight, 37.7% bio-based TPAE, 30.6% bio-based EVA, 29.7% bio-based POE, 1% cumene peroxide and 1% nano-silica with an average particle size of 10 nm.

[0103] The foamed shoe material was prepared according to the method in Example 12.

[0104] The performance test results of the foamed shoe materials of Examples 1-12 and Comparative Examples 1-4 are shown in Table 1 below.

[0105] Ball rebound: Tested according to GB / T6670-2008.

[0106] Density: Tested using a KW-300A microcomputer electronic densitometer.

[0107] Tensile strength: Tested according to the method of GB / T533-2008.

[0108] Table 1 Performance Test Results

[0109] Resilience / % <![CDATA[Density / g / cm 3 > Tensile strength / MPa Example 1 62 0.146 2.7 Example 2 61 0.150 2.4 Example 3 64 0.144 2.5 Example 4 62 0.147 2.5 Example 5 55 0.175 2.0 Example 6 60 0.152 2.4 Example 7 61 0.149 2.3 Example 8 52 0.182 1.8 Comparative Example 1 35 0.277 0.7 Comparative Example 2 47 0.214 1.4 Comparative Example 3 43 0.227 1.2 Example 9 64 0.142 3.2 Example 10 63 0.147 3.0 Example 11 62 0.138 2.9 Example 12 68 0.151 3.9 Comparative Example 4 38 0.291 1.2

[0110] In comparative examples 1 and 4, obvious delamination was observed after the samples fractured during tensile strength testing, indicating that the raw material components did not have good compatibility.

[0111] As can be seen from the results in Table 1 above, this application uses a variety of biomass raw materials as the main raw materials for shoe materials, which is highly environmentally friendly. After adding compatibilizers, foamed shoe materials with good foaming performance and good performance can be obtained. Moreover, the combination of two compatibilizers has a better compatibility effect than a single compatibilizer, which can make the raw material components more compatible.

[0112] This specific embodiment is merely an explanation of this application and is not intended to limit it. 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 fall within the scope of the claims of this application.

Claims

1. A foamed shoe material composition based on biomass raw materials, characterized in that, The raw material components, by 100% weight, comprise: 0-45% bio-based TPAE, 0-45% bio-based TPU, 20-37% bio-based EVA, 22-35% bio-based POE, and 5-15% compatibilizer; the sum of the weight percentages of the bio-based TPAE and the bio-based TPU is 30-45%; the compatibilizer is a combination of C12-C36 alkyl-terminated polyester polyurethane and C12-C36 alkyl-terminated alkyl polyurethane in a weight ratio of 1:9-9:1; the raw material components also comprise 0.5-3% peroxide curing agent, 0.5-1.5% nucleating agent, and 0.5-2% pigment; The C12-C36 alkyl-terminated polyester polyurethane is prepared by the following method: A polyester polyurethane prepolymer is reacted with a general formula C... n H 2n+1 R 1 The first compound is based on the NCO group and R 1 The reaction is carried out with a molar ratio of groups 1:1-3 to obtain the product, wherein R... 1 The amino group is hydroxyl, primary amino, or secondary amino, and n = 12-36; the polyester-based polyurethane prepolymer is prepared by the following method: polyester diol and IPDI or HMDI are added to a reaction vessel at a molar ratio of 0.55-0.85:1 and reacted at room temperature to 100°C for 2-10 hours to obtain the prepolymer; the polyester diol is selected from polyethylene terephthalate-1,4-cyclohexanediethanol ester; The average molecular weight of the polyester diol used in the polyester-based polyurethane prepolymer is 300-1500. The C12-C36 alkyl-terminated alkyl polyurethane is prepared by the following method: alkyl polyurethane prepolymer is reacted with C12-C36 alkyl-terminated alkyl polyurethane. m H 2m+1 R 2 The second compound is based on the NCO group and R 2 The reaction is carried out with a molar ratio of groups of 1:1 to 3 to obtain the product, wherein R is... 2 The alkyl polyurethane prepolymer is prepared by adding alkyl diol and diisocyanate monomer to a reaction vessel at a molar ratio of 0.55 to 0.9:1 and reacting at room temperature to 100°C for 2 to 10 hours.

2. The foamed shoe material composition based on biomass raw materials according to claim 1, characterized in that, The weight content of NCO groups in the polyester-based polyurethane prepolymer and the alkyl polyurethane prepolymer is 2-8%, respectively.

3. The foamed shoe material composition based on biomass raw materials according to claim 2, characterized in that, The alkyl diols used in the alkyl polyurethane prepolymer are C12-C24 alkyl diols.

4. The foamed shoe material composition based on biomass raw materials according to claim 3, characterized in that, The peroxide sulfide is selected from one or more combinations of dicumyl peroxide, di-tert-butyl peroxide, benzoyl peroxide, and bis(2,5-diphenyl) sulfide.

5. The foamed shoe material composition based on biomass raw materials according to claim 4, characterized in that, The nucleating agent is selected from one or a combination of several of nano-silica, nano-calcium carbonate, nano-titanium dioxide, nano-zinc oxide, nano-kaolin, nano-montmorillonite, and nano-attapulgite.

6. A foamed shoe material, characterized in that, The preparation method is as follows: The raw material components other than the peroxide vulcanizing agent in the foamed shoe material composition of any one of claims 1-5 are mixed and added to a screw extruder for extrusion granulation to obtain primary particles; the primary particles are mixed and kneaded evenly with the peroxide vulcanizing agent, then vulcanized in a mold, and foamed using supercritical fluid foaming technology.