High-content PCL (polycaprolactone) macromolecular copolymerized TPU (thermoplastic polyurethane) steam forming material as well as preparation method and application thereof

Abstract

The invention provides a high-content PCL (polycaprolactone) macromolecular copolymerized TPU (thermoplastic polyurethane) steam forming material as well as a preparation method and application thereof. The preparation raw materials comprise the following components: more than 99wt% of polyurethane; the raw materials comprise, by weight, 0.05 to 0.06% of an antioxidant, 0.165 to 0.175% of an ultraviolet light absorber and 0.1 to 0.2% of an anti-hydrolysis agent; the polyurethane is prepared from the following raw materials in percentage by weight: 5 to 5.5 percent of butanediol, 6.5 to 7 percent of oxalic acid, 60 to 61 percent of caprolactone, 24 to 24.5 percent of hexamethylene diisocyanate and 3.5 to 3.7 percent of neopentyl glycol. Polyurethane prepared from specific raw materials is used as a sole raw material, so that the PCL content in the prepared sole is as high as 60%, and the sole has light weight, cushioning and high resilience under a steam forming process.

Description

Technical Field

[0001] The invention belongs to the technical field of shoe midsole materials, and in particular relates to a high-content PCL polymer copolymer TPU steam molding material and a preparation method and application thereof. Background Art

[0002] In the field of footwear manufacturing, material selection and processing technology are crucial to improving product performance and comfort. PCL, as a biodegradable polymer material with good biocompatibility, has gradually attracted attention in recent years and has been tried in footwear manufacturing, especially in the development of midsole materials.

[0003] However, the application of PCL in existing technologies is mostly limited to low content, and the corresponding processing technology has not been fully optimized to fully tap the potential of PCL materials. Summary of the invention

[0004] In view of this, the object of the present invention is to provide a high-content PCL polymer copolymer TPU steam molding material and its preparation method and application. The molding material has a high PCL content, and the prepared midsole material has lightweight, shock absorption and high resilience.

[0005] The present invention provides a high-content PCL polymer copolymer TPU steam molding material, and the raw materials for preparation include the following components:

[0006] Polyurethane>99wt%; antioxidant 0.05-0.06wt%, ultraviolet absorber 0.165-0.175wt% and anti-hydrolysis agent 0.1-0.2wt%;

[0007] The polyurethane is prepared from the following raw materials:

[0008] Butanediol 5-5.5wt%, oxalic acid 6.5-7wt%, caprolactone 60-61wt%, hexamethylene diisocyanate 24-24.5wt% and neopentyl glycol 3.5-3.7wt%.

[0009] In a specific embodiment of the present invention, the polyurethane is 99-99.6%.

[0010] In a specific embodiment of the present invention, the content of polycaprolactone in the steam forming material is up to 60 wt%.

[0011] In a specific embodiment of the present invention, the antioxidant is triethylene glycol ether-di(3-tert-butyl-4-hydroxy-5-methylphenyl) propionate;

[0012] The ultraviolet absorber is N-(2-ethoxyphenyl)-N′-(2-ethylphenyl)-oxalamide;

[0013] The anti-hydrolysis agent is N,N'-di(2,6-diisopropylphenyl)carbodiimide.

[0014] The present invention provides a method for preparing a high-content PCL polymer copolymer TPU steam molding material according to the above technical solution, comprising the following steps:

[0015] The polyurethane, antioxidant, ultraviolet absorber and anti-hydrolysis agent are mixed and steam molding process is adopted to obtain a high-content PCL polymer copolymer TPU steam molding material;

[0016] The parameters of the steam forming process include:

[0017] The pressure of steam is 7KG±2, the pressure of water cooling is 4KG±1, and the pressure of air is 7KG±2;

[0018] The polyurethane is prepared from the following raw materials:

[0019] Butanediol 5-5.5wt%, oxalic acid 6.5-7wt%, caprolactone 60-61wt%, hexamethylene diisocyanate 24-24.5wt% and neopentyl glycol 3.5-3.7wt%.

[0020] In a specific embodiment of the present invention, the time for the mold transfer penetration is 23±5s, the time for the solid mold penetration is 23±5s; and the time for feeding is 12±3s.

[0021] In a specific implementation manner of the present invention, the time for mold transfer pressurization is 50±5s; the time for mold fixation pressurization is 50±5s; and the water cooling time is 90±10s.

[0022] In a specific embodiment of the present invention, the time for mold transfer penetration is 2.2±0.2 kg; the pressure of the mold transfer pressurized steam is 2.75±0.2 kg;

[0023] The pressure of the steam penetrating the solid mold is 2.2±0.2kg; the pressure of the steam pressurizing the solid mold is 2.75±0.2kg.

[0024] In a specific embodiment of the present invention, polyurethane is prepared according to the following method:

[0025] Mixing butanediol, oxalic acid and caprolactone, and carrying out esterification reaction in the presence of a catalyst to obtain polyester polyol;

[0026] The polyester polyol and neopentyl glycol are mixed, and hexamethylene diisocyanate is added dropwise to carry out a prepolymerization reaction to obtain a prepolymer;

[0027] The prepolymer is chain extended and then cured to obtain polyurethane.

[0028] The present invention provides a shoe midsole, which is made from the high-content PCL polymer copolymer TPU steam molding material described in the above technical solution.

[0029] The invention provides a high-content PCL polymer copolymer TPU steam molding material, the raw materials for preparation include the following components: polyurethane>99wt%; antioxidant 0.05-0.06wt%, ultraviolet absorber 0.165-0.175wt% and anti-hydrolysis agent 0.1-0.2wt%; the polyurethane is prepared from the following raw materials: butanediol 5-5.5wt%, oxalic acid 6.5-7%, caprolactone 60-61wt%, hexamethylene diisocyanate 24-24.5wt% and neopentyl glycol 3.5-3.7wt%. The invention adopts polyurethane prepared from specific raw materials as sole raw material, so that the PCL content in the prepared sole is as high as 60%, and then under the steam molding process, the sole has light weight, shock absorption and high resilience. DETAILED DESCRIPTION

[0030] The present invention provides a high-content PCL polymer copolymer TPU steam molding material, and the raw materials for preparation include the following components:

[0031] Polyurethane>99wt%; antioxidant 0.05-0.06wt%, ultraviolet absorber 0.165-0.175wt% and anti-hydrolysis agent 0.1-0.2wt%;

[0032] The polyurethane is prepared from the following raw materials:

[0033] Butanediol 5-5.5wt%, oxalic acid 6.5-7wt%, caprolactone 60-61wt%, hexamethylene diisocyanate 24-24.5wt% and neopentyl glycol 3.5-3.7wt%.

[0034] The present invention copolymerizes caprolactone and other high molecular monomers to make the PCL content of the steam-molded material as high as 60wt%. It is used in the preparation of shoe midsoles to make it lightweight, shock-absorbing and highly resilient, thereby improving the wearing comfort of the footwear and enhancing the sports performance; the extreme lightness and durability meet the stringent requirements of modern footwear on material performance.

[0035] The raw materials for preparing the steam forming material provided by the present invention include polyurethane>99wt%, preferably 99-99.6%. The polyurethane is prepared from the following raw materials:

[0036] Butanediol 5-5.5wt%, oxalic acid 6.5-7wt%, caprolactone 60-61wt%, hexamethylene diisocyanate 24-24.5wt% and neopentyl glycol 3.5-3.7wt%.

[0037] Specifically, the polyurethane is prepared according to the following method:

[0038] Mixing butanediol, oxalic acid and caprolactone, and carrying out esterification reaction in the presence of a catalyst to obtain polyester polyol;

[0039] The polyester polyol and neopentyl glycol are mixed, and hexamethylene diisocyanate is added dropwise to carry out a prepolymerization reaction to obtain a prepolymer;

[0040] The prepolymer is chain extended and then cured to obtain polyurethane.

[0041] In the present invention, oxalic acid is preferably oxalic acid dihydrate.

[0042] The esterification reaction in the present invention is carried out in the presence of a catalyst, the catalyst is a titanate or a stannate; the catalyst accounts for 0.15-0.25% of the mass of all raw materials, preferably 0.2%; all materials refer to the total amount of butanediol, oxalic acid, caprolactone, hexamethylene diisocyanate and neopentyl glycol. The esterification reaction is carried out under stirring conditions. The temperature of the esterification reaction in the present invention is 230-240°C, preferably 235°C; the time is 6-10h, preferably 8h. The prepolymerization reaction is carried out under stirring conditions; the temperature of the prepolymerization reaction is 210-220°C, and the time is 150-180min.

[0043] The present invention uses diol or diamine as a chain extender to further adjust the molecular weight and performance of the polyurethane; the diol is selected from one or more of ethylene glycol, propylene glycol, 1,4-butanediol and 1,3-butanediol; the diamine is selected from one or more of ethylenediamine, propylenediamine, 1,4-butanediamine and 1,3-butanediamine. The chain extender accounts for 5 to 30% of the total molar amount of all raw materials. The PCL content in the obtained polyurethane is 60 to 61%.

[0044] The present invention adds hexamethylene diisocyanate (HDI) dropwise while maintaining stirring to control the reaction rate and temperature.

[0045] In the present invention, the reaction mixture is poured into a mold for curing; the curing can be carried out at room temperature, preferably at 15 to 30° C.; or it can be carried out under heating conditions. After the curing is completed, the polyurethane material is taken out of the mold and necessary post-processing is carried out, such as cutting, grinding, etc.

[0046] The polyurethane is prepared from the following raw materials:

[0047] Butanediol 5-5.5wt%, oxalic acid 6.5-7wt%, caprolactone 60-61wt%, hexamethylene diisocyanate 24-24.5wt% and neopentyl glycol 3.5-3.7wt%.

[0048] In a specific embodiment of the present invention, the raw materials for preparing the polyurethane include:

[0049] Butanediol 5.38 wt%, oxalic acid dihydrate 6.75 wt%, caprolactone 60.12 wt%, hexamethylene diisocyanate (HDI) 24.11 wt% and neopentyl glycol 3.64 wt%.

[0050] The polycaprolactone (PCL) contained in the above-mentioned polyurethane is a degradable polyester with good biodegradability and biocompatibility; it has a low melting point, usually between 60 and 63°C, making it easier to handle during thermal processing and molding.

[0051] The antioxidant described in the present invention is triethylene glycol ether-di(3-tert-butyl-4-hydroxy-5-methylphenyl) propionate; the ultraviolet absorber is N-(2-ethoxyphenyl)-N′-(2-ethylphenyl)-oxalamide; and the anti-hydrolysis agent is N,N′-di(2,6-diisopropylphenyl)carbodiimide.

[0052] In a specific embodiment of the present invention, the high-content PCL polymer copolymer TPU steam molding material is prepared by raw materials including the following components:

[0053] Polyurethane 99.625wt%; antioxidant 0.055wt%, ultraviolet absorber 0.17wt% and anti-hydrolysis agent 0.15wt%.

[0054] The present invention provides a method for preparing a high-content PCL polymer copolymer TPU steam molding material according to the above technical solution, comprising the following steps:

[0055] The polyurethane, antioxidant, ultraviolet absorber and anti-hydrolysis agent are mixed and steam molding process is adopted to obtain a high-content PCL polymer copolymer TPU steam molding material;

[0056] The parameters of the steam forming process include:

[0057] The pressure of steam is 7KG±2, the pressure of water cooling is 4KG±1, and the pressure of air is 7KG±2;

[0058] The method provided by the present invention adopts a steam forming process to ensure forming accuracy and stability, protect material properties, improve wearing comfort and sports surface, meet environmental protection requirements, and reduce production costs. The steam forming process is efficient and fast, and can significantly improve the production efficiency of shoe midsoles. At the same time, the process also has good repeatability and stability, which helps to reduce production costs and improve product quality.

[0059] In the present invention, the pressure of steam is 7KG±2, the pressure of water cooling is 4KG±1, and the pressure of air is 7KG±2.

[0060] Mold shifting exhaust parameters: mold fixing time 5s, mold shifting time 5s, same row time 5s; mold fixing exhaust parameters: mold fixing time 18s, mold shifting time 5s, same row time 5s.

[0061] In the present invention, the time for the mold transfer penetration is 23±5s, the time for the solid mold penetration is 23±5s; and the time for feeding is 12±3s.

[0062] In the present invention, the time for mold shifting and pressurizing is 50±5s; the time for mold fixing and pressurizing is 50±5s; and the time for water cooling is 90±10s.

[0063] In the present invention, the time for mold shifting and pressurizing is 50±5s; the time for mold fixing and pressurizing is 50±5s; and the time for water cooling is 90±10s.

[0064] In the present invention, the time for mold transfer penetration is 2.2±0.2kg; the pressure of mold transfer pressurized steam is 2.75±0.2kg; the pressure of solid mold penetration steam is 2.2±0.2kg; the pressure of solid mold pressurized steam is 2.75±0.2kg.

[0065] In the present invention, the feed die gap is 24 mm ± 2, and the number of die pairs is 1 die / 1 pair.

[0066] The steam-molded material prepared by the method of the present invention has excellent lightness, shock absorption and high resilience, which brings a new breakthrough in the field of footwear manufacturing.

[0067] The present invention provides a shoe midsole, which is made from the high-content PCL polymer copolymer TPU steam molding material described in the above technical solution.

[0068] In order to further illustrate the present invention, a high-content PCL polymer copolymer TPU steam molding material provided by the present invention, a preparation method and application thereof are described in detail below in combination with embodiments, but they should not be understood as limiting the scope of protection of the present invention.

[0069] Example 1

[0070] 5.38 wt% of butanediol, 6.75% of oxalic acid dihydrate and 60.12% of PCL were added into a three-necked flask equipped with a stirrer, a thermometer and a condenser.

[0071] At a temperature of 235°C and with a catalyst of titanate, an esterification reaction was carried out for 8 hours to generate polyester polyols. This step required heating and decompression to remove the generated water, and continuous stirring at a speed of 1000 rpm to ensure a uniform reaction.

[0072] The temperature was lowered to 210-220°C, 3.64% neopentyl glycol was added, and the mixture was stirred evenly; 24.11% hexamethylene diisocyanate (HDI) was slowly added dropwise, and the mixture was stirred at 1000 rpm to control the reaction rate and temperature. The mixture was reacted for 160 minutes to obtain a polyurethane prepolymer;

[0073] The polyurethane prepolymer and the chain extender ethylene glycol are chain extended, and the obtained reaction mixture is poured into a mold and cured at room temperature. After the curing is completed, the mold is taken out to obtain a polyurethane; the PCL content in the polyurethane is 60.12%.

[0074] 99.625wt% of polyurethane, 0.055wt% of triethylene glycol ether-di(3-tert-butyl-4-hydroxy-5-methylphenyl) propionate, 0.17wt% of N-(2-ethoxyphenyl)-N′-(2-ethylphenyl)-oxalamide and 0.15wt% of N,N′-di(2,6-diisopropylphenyl)carbodiimide were mixed, and the steam molding process parameters shown in Table 1 were used to prepare a high-content PCL polymer copolymer TPU steam molding material as a midsole material;

[0075] Table 1 Steam forming process parameters

[0076]

[0077] The present invention performs a performance test on the prepared midsole material, and the results are shown in Table 2:

[0078] Table 2 Performance test results of midsole materials

[0079]

[0080]

[0081]

[0082]

[0083]

[0084] As can be seen from the above embodiments, the present invention provides a high-content PCL polymer copolymer TPU steam molding material, the raw materials for preparation include the following components: polyurethane>99wt%; antioxidant 0.05-0.06wt%, ultraviolet absorber 0.165-0.175wt% and anti-hydrolysis agent 0.1-0.2wt%; the polyurethane is prepared from the following raw materials: butanediol 5-5.5wt%, oxalic acid 6.5-7%, caprolactone 60-61wt%, hexamethylene diisocyanate 24-24.5wt% and neopentyl glycol 3.5-3.7wt%. The present invention adopts polyurethane prepared from specific raw materials as the sole raw material, so that the PCL content in the prepared sole is as high as 60%, and then under the steam molding process, it has light weight, shock absorption and high resilience.

[0085] The above is only a preferred embodiment of the present invention. It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the principle of the present invention. These improvements and modifications should also be regarded as the scope of protection of the present invention.

Claims

1. A high-content PCL polymer copolymer TPU steam molding material, the raw materials for preparation include the following components: Polyurethane>99wt%; antioxidant 0.05-0.06wt%, ultraviolet absorber 0.165-0.175wt% and anti-hydrolysis agent 0.1-0.2wt%; The polyurethane is prepared from the following raw materials: Butanediol 5-5.5wt%, oxalic acid 6.5-7%, caprolactone 60-61wt%, hexamethylene diisocyanate 24-24.5wt% and neopentyl glycol 3.5-3.6wt%.

2. The high-content PCL polymer copolymer TPU steam molding material according to claim 1, characterized in that: Polyurethane 99~99.6%.

3. The high-content PCL polymer copolymer TPU steam molding material according to claim 1, characterized in that: The polycaprolactone content in the steam forming material is as high as 60wt%.

4. The high-content PCL polymer copolymer TPU steam molding material according to claim 1, characterized in that: The antioxidant is triethylene glycol ether-di(3-tert-butyl-4-hydroxy-5-methylphenyl) propionate; The ultraviolet absorber is N-(2-ethoxyphenyl)-N′-(2-ethylphenyl)-oxalamide; The anti-hydrolysis agent is N,N'-di(2,6-diisopropylphenyl)carbodiimide.

5. A method for preparing the high-content PCL polymer copolymer TPU steam molding material according to claim 1, comprising the following steps: The polyurethane, antioxidant, ultraviolet absorber and anti-hydrolysis agent are mixed and steam molding process is adopted to obtain a high-content PCL polymer copolymer TPU steam molding material; The parameters of the steam forming process include: The pressure of steam is 7KG±2, the pressure of water cooling is 4KG±1, and the pressure of air is 7KG±2; The polyurethane is prepared from the following raw materials: Butanediol 5-5.5wt%, oxalic acid 6.5-7wt%, caprolactone 60-61wt%, hexamethylene diisocyanate 24-24.5wt% and neopentyl glycol 3.5-3.7wt%.

6. The preparation method according to claim 5, characterized in that: The time for mold penetration is 23±5s, the time for mold penetration is 23±5s; the time for material feeding is 12±3s.

7. The preparation method according to claim 5, characterized in that: The time for mold transfer and pressurization is 50±5s; the time for mold fixation and pressurization is 50±5s; and the water cooling time is 90±10s.

8. The preparation method according to claim 5, characterized in that: The time for mold transfer penetration is 2.2±0.2kg; the pressure of mold transfer pressurized steam is 2.75±0.2kg; The pressure of the steam penetrating the solid mold is 2.2±0.2kg; the pressure of the steam pressurizing the solid mold is 2.75±0.2kg.

9. The preparation method according to claim 5, characterized in that: Polyurethane is prepared as follows: Mixing butanediol, oxalic acid and caprolactone, and carrying out esterification reaction in the presence of a catalyst to obtain polyester polyol; The polyester polyol and neopentyl glycol are mixed, and hexamethylene diisocyanate is added dropwise to carry out a prepolymerization reaction to obtain a prepolymer; The prepolymer is chain extended and then cured to obtain polyurethane.

10. A shoe midsole made from the high-content PCL polymer copolymer TPU steam molding material according to any one of claims 1 to 4.

Images