Shoe material modified polyurethane hot melt adhesive for preventing screen cloth from hardening after high-temperature hot pressing

Abstract

The invention relates to a shoe material modified polyurethane hot melt adhesive for preventing screen cloth from hardening after high-temperature hot pressing. The modified polyurethane hot melt adhesive is prepared from the following raw materials: modified polyurethane resin, hydrogenated rosin glyceride, filler, oxidized polyethylene wax, glycerol monostearate, polyoxyethylene oleate, epoxy butyl stearate, polydimethylsiloxane, dibutyl maleate, alkylphenol polyoxyethylene ether and an antioxidant. Modified polyurethane resin serves as a main raw material, hydrogenated rosin glyceride is added on the premise that the adding amount of filler is reduced, oxidized polyethlene wax, polydimethylsilane and dibutyl maleate are introduced for cooperation, the bonding strength of the polyurethane hot melt adhesive is improved, and the toughness of the interior of the polyurethane hot melt adhesive is improved; the bonding firmness of the shoe material substrate and the mesh cloth is ensured, meanwhile, the problem that the polyurethane hot melt adhesive becomes hard after high-temperature hot pressing can be prevented, the problem that the shoe material becomes hard after the mesh cloth is compounded is effectively solved, and the softness of the shoe material after the mesh cloth is compounded is ensured.

Description

Technical Field

[0001] This invention belongs to the field of polyurethane hot melt adhesive preparation technology, specifically relating to a modified polyurethane hot melt adhesive for shoe materials that does not harden after high-temperature hot pressing of mesh fabric. Background Technology

[0002] Hot melt adhesive is a type of plastic adhesive whose physical state changes with temperature within a certain temperature range, while its chemical properties remain unchanged. It is non-toxic and odorless, making it an environmentally friendly chemical product. Because it is a solid, it is easy to package, transport, and store. It is solvent-free, pollution-free, and non-toxic. It is also favored for its simple production process, high added value, high bonding strength, and fast speed. Polyurethane is an emerging organic polymer material, known as the "fifth largest plastic." Due to its excellent performance, it is widely used in many sectors of the national economy, including light industry, chemical industry, electronics, textiles, medical, construction, building materials, automobiles, defense, aerospace, and aviation.

[0003] As people's requirements for clothing increase and new technologies and processes are applied in the production of shoe materials, new types of shoe materials are constantly emerging. The bonding of the shoe material base and the mesh fabric is generally done by hot melt adhesive. After the hot melt adhesive, which is mainly made of polyurethane resin, is used to bond the shoe material base and the mesh fabric, the shoe material is prone to hardening, which affects the subsequent use and wearing comfort of the shoe material, and needs further improvement. Summary of the Invention

[0004] The purpose of this invention is to overcome the shortcomings of the prior art and provide a modified polyurethane hot melt adhesive for shoe materials that does not harden after high-temperature hot pressing of mesh fabric.

[0005] The present invention adopts the following technical solution: A modified polyurethane hot melt adhesive for shoe materials that does not harden after high-temperature hot pressing of mesh fabric comprises the following raw materials in parts by weight: 100 parts modified polyurethane resin, 10-15 parts hydrogenated rosin glycerol ester, 10-12 parts filler, 3-6 parts oxidized polyethylene wax, 1-2 parts glyceryl monostearate, 2-4 parts polyoxyethylene oleate, 1-2 parts epoxy stearate butyl ester, 3-5 parts polydimethylsiloxane, 1-2 parts dibutyl maleate, 0.6-0.8 parts alkylphenol polyoxyethylene ether, and 0.5-1 parts antioxidant.

[0006] Furthermore, its preparation method specifically includes the following steps: Step 1: Mix the modified polyurethane resin, hydrogenated rosin resin, and filler in a specific ratio at 40-50℃ until homogeneous to obtain a premix. Step 2: Add the required weight parts of oxidized polyethylene wax, glyceryl monostearate, polydimethylsilane, and dibutyl maleate to the premix obtained in Step 1 and mix evenly. Heat to 108-118℃, then add oleic acid polyoxyethylene ester, epoxy stearate butyl ester, alkylphenol polyoxyethylene ether, and antioxidant and mix and stir evenly to obtain the premix. Step 3: The premix is ​​fed into a twin-screw reactor for reaction and plasticization, and then pelletized underwater to obtain the modified polyurethane hot melt adhesive for shoe materials.

[0007] Furthermore, the filler is composed of talc powder and calcium carbonate in a weight ratio of 1:2.

[0008] Furthermore, the antioxidant is composed of trinonylphenyl phosphite and antioxidant 1010 in a weight ratio of 2:1.

[0009] Furthermore, the modified polyurethane hot melt adhesive is composed of the following raw materials in parts by weight: 30-70 parts of polycaprolactone diol, 70-130 parts of polytetrahydrofuran diol, 10-30 parts of toluene diisocyanate, 2-8 parts of dicarboxymethyl propionic acid, 0.3-1.6 parts of 1,4-butanediol, 3-5 parts of triethylamine, 0.1-0.5 parts of polyvinyl acetate, and 220-360 parts of dimethylformamide.

[0010] Furthermore, the preparation method of the modified polyurethane resin specifically includes the following steps: Step 1: Add polycaprolactone diol and polytetrahydrofuran diol to the reaction vessel, heat to 105°C to dehydrate for one hour, then cool down to 55°C, add toluene diisocyanate, heat up to 90°C, keep the reaction at this temperature for 2 hours, determine the NCO content, and cool down to 50°C after reaching the theoretical value. Step 2: Continue to add dicarboxymethyl propionic acid and polyvinyl acetate to the reactor, heat to 80°C, maintain the temperature for 2 hours, then cool to 45°C, add 1,4-butanediol, heat to 70°C, maintain the temperature for 3 hours, then add triethylamine and dimethylformamide to the reactor, mix and stir evenly, then cool to 50°C and discharge to obtain the modified polyurethane resin.

[0011] Furthermore, the molecular weight of the polycaprolactone diol is 2000, and the molecular weight of the polytetrahydrofuran diol is 2000.

[0012] As can be seen from the above description of the present invention, compared with the prior art, the beneficial effects of the present invention are as follows: This application, by limiting the raw material composition of the modified polyurethane hot melt adhesive, uses modified polyurethane resin as the main raw material, and adds hydrogenated rosin glycerol ester while reducing the amount of filler added, and introduces oxidized polyethylene wax, polydimethylsilane, and dibutyl maleate to improve the bonding strength of the polyurethane hot melt adhesive and improve the internal toughness of the polyurethane hot melt adhesive. While ensuring the bonding strength between the shoe material base and the mesh fabric, it can also prevent the problem of hardening of the polyurethane hot melt adhesive after high temperature hot pressing, effectively overcoming the problem of hardening of the shoe material after mesh fabric composite, and ensuring the softness of the shoe material after mesh fabric composite; the raw material composition also introduces epoxy stearate butyl ester and oleic acid polyoxyethylene ester to increase the compatibility and adhesion between the raw materials, so as to ensure the bonding performance of the prepared polyurethane hot melt adhesive. Further limiting the raw material composition and preparation method of modified polyurethane resin, and introducing polyvinyl acetate in combination with other raw materials, the prepared modified polyurethane resin has a lower modulus and better physical properties such as elongation and tensile strength, thereby improving the performance of modified polyurethane hot melt adhesive, making the composite mesh shoe material soft and non-stiff. Detailed Implementation

[0013] The present invention will be further described below through specific embodiments.

[0014] A modified polyurethane hot melt adhesive for shoe materials that prevents hardening after high-temperature hot pressing of mesh fabric comprises the following raw materials in parts by weight: 100 parts modified polyurethane resin, 10-15 parts hydrogenated rosin glycerol ester, 10-12 parts filler, 3-6 parts oxidized polyethylene wax, 1-2 parts glyceryl monostearate, 2-4 parts polyoxyethylene oleate, 1-2 parts epoxy stearate butyl ester, 3-5 parts polydimethylsiloxane, 1-2 parts dibutyl maleate, 0.6-0.8 parts alkylphenol polyoxyethylene ether, and 0.5-1 parts antioxidant. The filler is composed of talc and calcium carbonate in a weight ratio of 1:2; the antioxidant is composed of trinonylphenyl phosphite and antioxidant 1010 in a weight ratio of 2:1.

[0015] The modified polyurethane hot melt adhesive is composed of the following raw materials in parts by weight: 30-70 parts polycaprolactone diol, 70-130 parts polytetrahydrofuran diol, 10-30 parts toluene diisocyanate, 2-8 parts dicarboxymethyl propionic acid, 0.3-1.6 parts 1,4-butanediol, 3-5 parts triethylamine, 0.1-0.5 parts polyvinyl acetate, and 220-360 parts dimethylformamide, wherein the molecular weight of both polycaprolactone diol and polytetrahydrofuran diol is 2000. Specifically, its preparation method includes the following steps: Step 1: Add polycaprolactone diol and polytetrahydrofuran diol to the reaction vessel, heat to 105°C to dehydrate for one hour, then cool down to 55°C, add toluene diisocyanate, heat up to 90°C, keep the reaction at this temperature for 2 hours, determine the NCO content, and cool down to 50°C after reaching the theoretical value. Step 2: Continue to add dicarboxymethyl propionic acid and polyvinyl acetate to the reactor, heat to 80°C, maintain the temperature for 2 hours, then cool to 45°C, add 1,4-butanediol, heat to 70°C, maintain the temperature for 3 hours, then add triethylamine and dimethylformamide to the reactor, mix and stir evenly, then cool to 50°C and discharge to obtain the modified polyurethane resin.

[0016] The preparation method of modified polyurethane hot melt adhesive for shoe materials specifically includes the following steps: Step 1: Mix the modified polyurethane resin, hydrogenated rosin resin, and filler in a specific ratio at 40-50℃ until homogeneous to obtain a premix. Step 2: Add the required weight parts of oxidized polyethylene wax, glyceryl monostearate, polydimethylsilane, and dibutyl maleate to the premix obtained in Step 1 and mix evenly. Heat to 108-118℃, then add oleic acid polyoxyethylene ester, epoxy stearate butyl ester, alkylphenol polyoxyethylene ether, and antioxidant and mix and stir evenly to obtain the premix. Step 3: The premix is ​​fed into a twin-screw reactor for reaction and plasticization, and then pelletized underwater to obtain the modified polyurethane hot melt adhesive for shoe materials.

[0017] Example 1 A modified polyurethane hot melt adhesive for shoe materials that does not harden after high-temperature hot pressing of mesh fabric comprises the following raw materials in parts by weight: 100 parts modified polyurethane resin, 15 parts hydrogenated rosin glycerol ester, 10 parts filler, 3 parts oxidized polyethylene wax, 2 parts glyceryl monostearate, 2 parts polyoxyethylene oleate, 2 parts epoxy stearate butyl ester, 3 parts polydimethylsiloxane, 2 parts dibutyl maleate, 0.6 parts alkylphenol polyoxyethylene ether, and 1 part antioxidant.

[0018] The preparation method of modified polyurethane hot melt adhesive specifically includes the following steps: Step 1: Add 42.6g of polycaprolactone diol and 115.6g of polytetrahydrofuran diol to the reaction vessel, heat to 105℃ to dehydrate for one hour, then cool down to 55℃, add 22.8g of toluene diisocyanate, heat up to 90℃, keep the reaction at this temperature for 2 hours, determine the NCO content, and cool down to 50℃ after reaching the theoretical value. Step 2: Continue to add 5.25g of dicarboxymethylpropionic acid and 0.36g of polyvinyl acetate to the reactor, raise the temperature to 80°C, and keep the reaction at this temperature for 2 hours. Then, lower the temperature to 45°C, add 1.28g of 1,4-butanediol, raise the temperature to 70°C, and keep the reaction at this temperature for 3 hours. Next, add 3.9g of triethylamine and 270g of dimethylformamide to the reactor, mix and stir evenly, and then lower the temperature to 50°C to discharge the modified polyurethane resin.

[0019] The preparation method of modified polyurethane hot melt adhesive for shoe materials specifically includes the following steps: Step 1: Mix the modified polyurethane resin, hydrogenated rosin resin, and filler in a specific ratio at 40°C until homogeneous to obtain a premix. Step 2: Add the required weight parts of oxidized polyethylene wax, glyceryl monostearate, polydimethylsilane, and dibutyl maleate to the premix obtained in Step 1 and mix evenly. Heat to 108°C and then add oleic acid polyoxyethylene ester, epoxy stearate butyl ester, alkylphenol polyoxyethylene ether, and antioxidant and mix and stir evenly to obtain the premix. Step 3: The premix is ​​fed into a twin-screw reactor for reaction and plasticization, and then pelletized underwater to obtain the modified polyurethane hot melt adhesive for shoe materials.

[0020] Example 2 A modified polyurethane hot melt adhesive for shoe materials that does not harden after high-temperature hot pressing of mesh fabric comprises the following raw materials in parts by weight: 100 parts modified polyurethane resin, 10 parts hydrogenated rosin glycerol ester, 12 parts filler, 6 parts oxidized polyethylene wax, 1 part glyceryl monostearate, 4 parts polyoxyethylene oleate, 1 part epoxy stearate butyl ester, 5 parts polydimethylsiloxane, 1 part dibutyl maleate, 0.8 parts alkylphenol polyoxyethylene ether, and 0.5 parts antioxidant.

[0021] The preparation method of modified polyurethane hot melt adhesive specifically includes the following steps: Step 1: Add 42.6g of polycaprolactone diol and 115.6g of polytetrahydrofuran diol to the reaction vessel, heat to 105℃ to dehydrate for one hour, then cool down to 55℃, add 22.8g of toluene diisocyanate, heat up to 90℃, keep the reaction at this temperature for 2 hours, determine the NCO content, and cool down to 50℃ after reaching the theoretical value. Step 2: Continue to add 5.25g of dicarboxymethylpropionic acid and 0.36g of polyvinyl acetate to the reactor, raise the temperature to 80°C, and keep the reaction at this temperature for 2 hours. Then, lower the temperature to 45°C, add 1.28g of 1,4-butanediol, raise the temperature to 70°C, and keep the reaction at this temperature for 3 hours. Next, add 3.9g of triethylamine and 270g of dimethylformamide to the reactor, mix and stir evenly, and then lower the temperature to 50°C to discharge the modified polyurethane resin.

[0022] The preparation method of modified polyurethane hot melt adhesive for shoe materials specifically includes the following steps: Step 1: Mix the modified polyurethane resin, hydrogenated rosin resin, and filler at 50°C in a specific ratio to obtain a premix. Step 2: Add the required weight parts of oxidized polyethylene wax, glyceryl monostearate, polydimethylsilane, and dibutyl maleate to the premix obtained in Step 1 and mix evenly. Heat to 118°C and then add oleic acid polyoxyethylene ester, epoxy stearate butyl ester, alkylphenol polyoxyethylene ether, and antioxidant and mix and stir evenly to obtain the premix. Step 3: The premix is ​​fed into a twin-screw reactor for reaction and plasticization, and then pelletized underwater to obtain the modified polyurethane hot melt adhesive for shoe materials.

[0023] Example 3 A modified polyurethane hot melt adhesive for shoe materials that does not harden after high-temperature hot pressing of mesh fabric comprises the following raw materials in parts by weight: 100 parts modified polyurethane resin, 12 parts hydrogenated rosin glycerol ester, 11 parts filler, 5 parts oxidized polyethylene wax, 1.5 parts glyceryl monostearate, 3 parts polyoxyethylene oleate, 1.5 parts epoxy stearate butyl ester, 4 parts polydimethylsiloxane, 1.5 parts dibutyl maleate, 0.7 parts alkylphenol polyoxyethylene ether, and 0.7 parts antioxidant.

[0024] The preparation method of modified polyurethane hot melt adhesive specifically includes the following steps: Step 1: Add 42.6g of polycaprolactone diol and 115.6g of polytetrahydrofuran diol to the reaction vessel, heat to 105℃ to dehydrate for one hour, then cool down to 55℃, add 22.8g of toluene diisocyanate, heat up to 90℃, keep the reaction at this temperature for 2 hours, determine the NCO content, and cool down to 50℃ after reaching the theoretical value. Step 2: Continue to add 5.25g of dicarboxymethylpropionic acid and 0.36g of polyvinyl acetate to the reactor, raise the temperature to 80°C, and keep the reaction at this temperature for 2 hours. Then, lower the temperature to 45°C, add 1.28g of 1,4-butanediol, raise the temperature to 70°C, and keep the reaction at this temperature for 3 hours. Next, add 3.9g of triethylamine and 270g of dimethylformamide to the reactor, mix and stir evenly, and then lower the temperature to 50°C to discharge the modified polyurethane resin.

[0025] The preparation method of modified polyurethane hot melt adhesive for shoe materials specifically includes the following steps: Step 1: Mix the modified polyurethane resin, hydrogenated rosin resin, and filler at 45°C in a specific ratio to obtain a premix. Step 2: Add the required weight parts of oxidized polyethylene wax, glyceryl monostearate, polydimethylsilane, and dibutyl maleate to the premix obtained in Step 1 and mix evenly. Heat to 116°C and then add oleic acid polyoxyethylene ester, epoxy stearate butyl ester, alkylphenol polyoxyethylene ether, and antioxidant and mix and stir evenly to obtain the premix. Step 3: The premix is ​​fed into a twin-screw reactor for reaction and plasticization, and then pelletized underwater to obtain the modified polyurethane hot melt adhesive for shoe materials.

[0026] The modified polyurethane hot melt adhesives prepared in Examples 1-3 were used to bond and laminate mesh fabrics to shoe material substrates to obtain shoe material samples. The obtained shoe material samples were then subjected to corresponding tests. The specific test results are shown in Table 1. The peel strength was tested according to the provisions of GB / T8949-1995. The folding endurance test was conducted according to the provisions of QB / T1646-2007. The samples were folded face-in at 23±2℃, and the changes in the folded parts on both sides were observed.

[0027] Table 1 Test Results of Each Embodiment Test Project Example 1 Try Theory 2 Example 3 Peel strength (N / m) 44 43 48 Flexural endurance test (23±2℃) No cracking after 150,000 cycles No cracking after 150,000 cycles No cracking after 150,000 cycles feel Soft and not hard Soft and not hard Soft and not hard As shown in the table above, this application limits the raw material composition of the modified polyurethane hot melt adhesive, using modified polyurethane resin as the main raw material. Under the premise of reducing the amount of filler added, hydrogenated rosin glycerol ester is added, and oxidized polyethylene wax, polydimethylsilane, and dibutyl maleate are introduced to improve the bonding strength of the polyurethane hot melt adhesive and improve the internal toughness of the polyurethane hot melt adhesive. While ensuring the bonding strength between the shoe material base and the mesh fabric, it can also prevent the problem of hardening of the polyurethane hot melt adhesive after high temperature hot pressing. It effectively overcomes the problem of hardening of the shoe material after mesh fabric composite and ensures the softness of the shoe material after mesh fabric composite.

[0028] The above description is merely a preferred embodiment of the present invention and should not be construed as limiting the scope of the present invention. All equivalent changes and modifications made in accordance with the scope of the present invention and the contents of the specification should still fall within the scope of the present invention.

Claims

1. A modified polyurethane hot melt adhesive for shoe materials that does not harden after high-temperature hot pressing of mesh fabric, characterized in that: The raw materials include the following parts by weight: 100 parts modified polyurethane resin, 10-15 parts hydrogenated rosin glycerol ester, 10-12 parts filler, 3-6 parts oxidized polyethylene wax, 1-2 parts glyceryl monostearate, 2-4 parts polyoxyethylene oleate, 1-2 parts epoxy stearate butyl ester, 3-5 parts polydimethylsiloxane, 1-2 parts dibutyl maleate, 0.6-0.8 parts alkylphenol polyoxyethylene ether, and 0.5-1 parts antioxidant.

2. The modified polyurethane hot melt adhesive for shoe materials that does not harden after high-temperature hot pressing of mesh fabric, as described in claim 1, is characterized in that: Its preparation method specifically includes the following steps: Step 1: Mix the modified polyurethane resin, hydrogenated rosin resin, and filler in a specific ratio at 40-50℃ until homogeneous to obtain a premix. Step 2: Add the required weight parts of oxidized polyethylene wax, glyceryl monostearate, polydimethylsilane, and dibutyl maleate to the premix obtained in Step 1 and mix evenly. Heat to 108-118℃, then add oleic acid polyoxyethylene ester, epoxy stearate butyl ester, alkylphenol polyoxyethylene ether, and antioxidant and mix and stir evenly to obtain the premix. Step 3: The premix is ​​fed into a twin-screw reactor for reaction and plasticization, and then pelletized underwater to obtain the modified polyurethane hot melt adhesive for shoe materials.

3. The modified polyurethane hot melt adhesive for shoe materials that does not harden after high-temperature hot pressing of mesh fabric, as described in claim 1, is characterized in that: The filler is composed of talc and calcium carbonate in a weight ratio of 1:

2.

4. The modified polyurethane hot melt adhesive for shoe materials that does not harden after high-temperature hot pressing of mesh fabric, as described in claim 1, is characterized in that: The antioxidant is composed of trinonylphenyl phosphite and antioxidant 1010 in a weight ratio of 2:

1.

5. The modified polyurethane hot melt adhesive for shoe materials that does not harden after high-temperature hot pressing of mesh fabric, as described in claim 1, is characterized in that: The modified polyurethane hot melt adhesive is composed of the following raw materials in parts by weight: 30-70 parts of polycaprolactone diol, 70-130 parts of polytetrahydrofuran diol, 10-30 parts of toluene diisocyanate, 2-8 parts of dicarboxymethyl propionic acid, 0.3-1.6 parts of 1,4-butanediol, 3-5 parts of triethylamine, 0.1-0.5 parts of polyvinyl acetate, and 220-360 parts of dimethylformamide.

6. The modified polyurethane hot melt adhesive for shoe materials that does not harden after high-temperature hot pressing of mesh fabric, as described in claim 5, is characterized in that: The preparation method of the modified polyurethane resin specifically includes the following steps: Step 1: Add polycaprolactone diol and polytetrahydrofuran diol to the reaction vessel, heat to 105°C to dehydrate for one hour, then cool down to 55°C, add toluene diisocyanate, heat up to 90°C, keep the reaction at this temperature for 2 hours, determine the NCO content, and cool down to 50°C after reaching the theoretical value. Step 2: Continue to add dicarboxymethyl propionic acid and polyvinyl acetate to the reactor, heat to 80°C, maintain the temperature for 2 hours, then cool to 45°C, add 1,4-butanediol, heat to 70°C, maintain the temperature for 3 hours, then add triethylamine and dimethylformamide to the reactor, mix and stir evenly, then cool to 50°C and discharge to obtain the modified polyurethane resin.

7. The modified polyurethane hot melt adhesive for shoe materials that does not harden after high-temperature hot pressing of mesh fabric, as described in claim 5, is characterized in that: The molecular weight of the polycaprolactone diol is 2000, and the molecular weight of the polytetrahydrofuran diol is 2000.