CN118406206A - Aging-resistant PU sole material and preparation method thereof - Google Patents

Abstract

The invention discloses an aging-resistant PU sole material and a preparation method thereof, belonging to the technical field of sole materials. The PU sole material comprises the following raw materials in parts by weight: 80-100 parts of isocyanate, 70-80 parts of polyester polyol, 7-10 parts of chain extender, 0.5-1 part of foam stabilizer, 0.4-0.5 part of water, 0.6-1.2 parts of catalyst and 0.5-0.8 part of anti-aging agent. The benzotriazole structure, the hindered phenol structure and the hindered amine structure in the anti-aging agent cooperate to endow the PU sole material with excellent anti-aging effect; in addition, a plurality of hydroxyl groups in the anti-aging agent can generate chemical action with isocyanate groups under the action of the catalyst, so that the anti-aging agent can stably exist in sole materials, and the lasting and efficient anti-aging effect is fully exerted.

Description

A kind of anti-aging PU sole material and preparation method thereof

Technical Field

The invention belongs to the technical field of sole materials, and in particular relates to an anti-aging PU sole material and a preparation method thereof.

Background technique

There are many types of sole materials, which are generally divided into natural sole materials and synthetic sole materials. Natural sole materials include natural leather, bamboo, wood, etc., and synthetic sole materials include rubber, ethylene-vinyl acetate (EVA), polyurethane (PU), polyvinyl chloride (PVC), etc. The common characteristics of sole materials are wear resistance, water resistance, good elasticity, easy to fit the foot shape, and not easy to deform after shaping. At present, synthetic sole materials are the most widely used type of shoe materials.

As a kind of synthetic shoe material, PU sole material is becoming more and more popular among consumers due to its lightness, wear resistance, good elasticity, anti-skid and oil resistance, and comfortable wearing. PU sole materials are divided into two types: polyester and polyether, and account for more than 80% of the domestic polyurethane sole material market. However, under the influence of light, oxygen, temperature, chemical media, biologically active media, etc., PU sole materials are prone to changes in the surface of the material or the physical and chemical properties and mechanical properties of the material, and eventually gradually lose their original excellent performance, resulting in aging and failure of the material. This is an irreversible physical and chemical change. This aging greatly affects the life of the polyurethane sole material. Therefore, it is necessary to modify the polyurethane material to improve its aging resistance.

Summary of the invention

The purpose of the present invention is to overcome the defects of the prior art and provide an anti-aging PU sole material and a preparation method thereof.

The purpose of the present invention can be achieved through the following technical solutions:

An anti-aging PU sole material comprises the following raw materials in parts by weight: 80-100 parts of isocyanate, 70-80 parts of polyester polyol, 7-10 parts of chain extender, 0.5-1 part of foam leveling agent, 0.4-0.5 part of water, 0.6-1.2 parts of catalyst, and 0.5-0.8 parts of anti-aging agent;

Furthermore, the isocyanate is one or more of polymethylene polyphenyl isocyanate, toluene diisocyanate and diphenylmethane diisocyanate.

Furthermore, the polyester polyol is a polyester polyol obtained by polycondensation of one of ethylene glycol, 1,4-butanediol and 1,6-hexanediol with adipic acid.

Furthermore, the chain extender is one or more of ethylene glycol, 1,4-butanediol, and propylene glycol.

Furthermore, the foam leveling agent is polydimethylsiloxane.

Furthermore, the catalyst is one or more of triethanolamine, triethylenediamine, triethylenediamine and N,N-dimethylcyclohexylamine.

Furthermore, the anti-aging agent is prepared by the following steps:

S1. Add 4-amino-2,6-di-tert-butylphenol and chloroform into a dry brown four-necked flask under nitrogen protection, stir to dissolve, then slowly add glycidol, raise the temperature to 60°C after the addition is complete, keep the temperature for reaction for 4 hours, cool to room temperature after the reaction is completed, distill under reduced pressure, purify by column chromatography (select a mixed solvent of chloroform and ether as the eluent, the volume ratio of chloroform to ether is 9:1), and distill under reduced pressure to obtain intermediate 1; the amount ratio of 4-amino-2,6-di-tert-butylphenol, glycidol and chloroform is 11.1g:3.5g:160mL;

The -NH ₂ of 4-amino-2,6-di-tert-butylphenol and the epoxy group of glycidol undergo a nucleophilic addition reaction under heating conditions. The reaction process is as follows:

S2. Under nitrogen protection, add intermediate 1 and dimethyl sulfoxide to a dry four-necked flask, stir to dissolve, add anhydrous sodium carbonate, and then slowly add 3-chloro-1,2-propylene glycol, stir until mixed evenly, heat to 80°C, keep warm for 3 hours, cool to room temperature after the reaction, distill under reduced pressure, wash with deionized water 3 times, and dry at 110°C for 12 hours to obtain intermediate 2; the amount ratio of intermediate 1, 3-chloro-1,2-propylene glycol, anhydrous sodium carbonate and dimethyl sulfoxide is 11.8 g:3.7 mL:9.3 g:220 mL;

Under the action of anhydrous sodium carbonate, the molar ratio of intermediate 1 and 3-chloro-1,2-propylene glycol is controlled to be 1:1 and 3-chloro-1,2-propylene glycol is slightly excessive, and the -NH- of intermediate 1 and the -Cl of 3-chloro-1,2-propylene glycol undergo nucleophilic substitution reaction. The reaction process is as follows:

S3. Under nitrogen protection, add intermediate 2, triethylamine and DMF (N,N-dimethylformamide) to a dry brown four-necked flask and stir until completely dissolved. Then slowly add a mixed solution of UV-327 (2-(3,5-di-tert-butyl-2-hydroxyphenyl)-5-chlorobenzotriazole) and DMF to the above four-necked flask, and then stir and react at 80°C for 8h. After the reaction is completed, cool to room temperature, distill under reduced pressure, wash with deionized water 3 times, wash with acetone 3 times, and finally dry in a vacuum oven at 60°C to constant weight to obtain intermediate 3; the amount ratio of intermediate 2, UV-327, triethylamine and DMF is 8.5g:8.6g:6.7mL:180mL;

Under the action of triethylamine, the molar ratio of intermediate 2 and UV-327 is controlled to be 1:1.05-1.1, and a -OH of intermediate 2 and -Cl of UV-327 undergo a substitution reaction. The reaction process is as follows:

S4. Add intermediate 3, 2-(2,2,6,6-tetramethylpiperidin-4-yl)acetic acid and DMF to a four-necked flask under nitrogen protection, stir until completely dissolved, then slowly add concentrated sulfuric acid, stir and heat to 110°C for reaction for 3 hours, cool to room temperature after the reaction, add sodium bicarbonate solution for neutralization, shake and stand for stratification, take the organic phase, dry it with anhydrous magnesium sulfate, filter, and distill the filtrate under reduced pressure to obtain an antioxidant. The amount ratio of intermediate 3, 2-(2,2,6,6-tetramethylpiperidin-4-yl)acetic acid, concentrated sulfuric acid and DMF is 14.5g:4.4g:1.3mL:200mL.

Under concentrated sulfuric acid and heating conditions, the molar ratio of intermediate 3 and 2-(2,2,6,6-tetramethylpiperidin-4-yl)acetic acid is controlled to be 1:1.05-1.1, and intermediate 3 and 2-(2,2,6,6-tetramethylpiperidin-4-yl)acetic acid undergo esterification reaction. The reaction process is as follows:

The anti-aging agent of the present invention contains benzotriazole structure, hindered phenol structure and hindered amine structure. The benzotriazole structure contains multiple conjugated double bonds and aromatic rings. The special molecular structure and internal action enable it to strongly absorb ultraviolet rays of 300-400 nanometers, excite its electrons to a high energy level, thereby converting ultraviolet energy into heat energy or light energy, thereby achieving an anti-aging effect; in the hindered phenol structure, there is a tert-butyl group on both sides of the -OH on the benzene ring. Since the hydroxyl group is restricted by spatial obstacles, the hydrogen atom is easily detached from the original molecular structure, thereby achieving the effect of donating protons and combining with peroxyl radicals, alkyl radicals, hydroxyl radicals, etc., causing them to lose their original activity, resulting in the termination of oxygen aging reaction, thereby achieving an anti-aging effect; the hindered amine structure achieves a light protection effect by capturing free radicals, decomposing hydroperoxides, quenching singlet oxygen and capturing heavy metal ions, and the hindered amine structure has a high light stabilization efficiency. The three anti-aging structures work synergistically to jointly give the sole material an excellent anti-aging effect.

The anti-aging agent of the present invention contains multiple hydroxyl groups, which can produce chemical reactions with isocyanate groups under the action of a catalyst, so that the anti-aging agent of the present invention can stably exist in the sole material, give full play to the long-lasting and efficient anti-aging effect, and will not migrate or fall out due to the influence of the external environment, resulting in a reduction in the anti-aging effect.

A method for preparing an anti-aging PU sole material comprises the following steps:

Weigh the raw materials in proportion, mix the polyester polyol, chain extender, foaming agent and catalyst at 75°C for 1 hour, then cool to 40°C, add water and anti-aging agent, mix for another 1 hour, then add isocyanate, stir quickly and evenly, and obtain the PU sole material through casting, aging and demoulding.

The beneficial effects of the present invention are as follows: the benzotriazole structure, hindered phenol structure and hindered amine structure in the anti-aging agent work synergistically to give the PU sole material an excellent anti-aging effect; in addition, the multiple hydroxyl groups in the anti-aging agent can react chemically with the isocyanate group under the action of a catalyst, so that the anti-aging agent of the present invention can stably exist in the sole material, giving full play to the long-lasting and efficient anti-aging effect.

Detailed ways

The following will be combined with the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

Example 1

The preparation of the anti-aging agent comprises the following specific steps:

S1. Under nitrogen protection, add 11.1 g of 4-amino-2,6-di-tert-butylphenol and 160 mL of chloroform into a dry 250 mL brown four-necked flask, stir to dissolve, then slowly add 3.5 g of glycidol, raise the temperature to 60°C after the addition, keep the temperature for 4 hours, cool to room temperature after the reaction, distill under reduced pressure, purify by column chromatography (select a mixed solvent of chloroform and ether as the eluent, the volume ratio of chloroform to ether is 9:1), and distill under reduced pressure to obtain intermediate 1;

S2. Under nitrogen protection, add 11.8 g of intermediate 1 and 220 mL of dimethyl sulfoxide into a dry 500 mL four-necked flask, stir to dissolve, add 9.3 g of anhydrous sodium carbonate, and then slowly add 3.7 mL of 3-chloro-1,2-propanediol, stir until mixed evenly, heat to 80 ° C, keep warm for 3 h, cool to room temperature after the reaction is completed, distill under reduced pressure, wash with deionized water 3 times, and dry at 110 ° C for 12 h to obtain intermediate 2;

S3, under nitrogen protection, 8.5g of intermediate 2, 6.7mL of triethylamine and 90mL of DMF were added to a dry 500mL brown four-necked flask, stirred until completely dissolved, and then 8.6g of a mixed solution of UV-327 and 90mL of DMF was slowly added to the above 500mL four-necked flask, followed by stirring and reacting at 80°C for 8h. After the reaction was completed, it was cooled to room temperature, distilled under reduced pressure, washed with deionized water 3 times, washed with acetone 3 times, and finally dried in a vacuum oven at 60°C to constant weight to obtain intermediate 3;

S4. Under nitrogen protection, add 14.5g of intermediate 3, 4.4g of 2-(2,2,6,6-tetramethylpiperidin-4-yl)acetic acid and 200mL of DMF into a 500mL four-necked flask, stir until completely dissolved, then slowly add 1.3mL of concentrated sulfuric acid, stir and heat to 110°C for 3h, cool to room temperature after the reaction, add sodium bicarbonate solution for neutralization, shake and let stand to separate, take the organic phase, dry it with anhydrous magnesium sulfate, filter, and distill the filtrate under reduced pressure to obtain an anti-aging agent.

Example 2

Preparation of PU sole material, the specific steps are as follows:

70 parts of polyester polyol obtained by polycondensation of ethylene glycol and adipic acid, 7 parts of 1,4-butanediol, 0.5 parts of polydimethylsiloxane, and 0.6 parts of triethanolamine were mixed at 75°C for 1 hour, then cooled to 40°C, 0.4 parts of water and 0.5 parts of the anti-aging agent of Example 1 were added, and mixed for another 1 hour. Then 80 parts of diphenylmethane diisocyanate were added, and the mixture was quickly stirred evenly. The PU sole material was obtained by casting, aging, and demolding.

Example 3

Preparation of PU sole material, the specific steps are as follows:

78 parts of polyester polyol obtained by polycondensation of 1,4-butanediol and adipic acid, 9 parts of ethylene glycol, 0.8 parts of polydimethylsiloxane and 1 part of triethylenediamine were mixed at 75°C for 1 hour, then cooled to 40°C, 0.45 parts of water and 0.7 parts of the anti-aging agent of Example 1 were added, and mixed for another 1 hour. Then 95 parts of diphenylmethane diisocyanate were added, and the mixture was quickly stirred evenly. The PU sole material was obtained by casting, aging and demolding.

Example 4

Preparation of PU sole material, the specific steps are as follows:

80 parts of polyester polyol obtained by condensation polymerization of 1,6-hexanediol and adipic acid, 10 parts of propylene glycol, 1 part of polydimethylsiloxane, and 1.2 parts of N,N-dimethylcyclohexylamine were mixed at 75°C for 1 hour, then cooled to 40°C, 0.5 parts of water and 0.8 parts of the anti-aging agent of Example 1 were added, and mixed for another 1 hour. Then 100 parts of polymethylene polyphenyl isocyanate were added, and the mixture was quickly stirred evenly. The PU sole material was obtained by casting, aging, and demolding.

Comparative Example 1

Preparation of PU sole material, the specific steps are as follows:

The remaining steps remain unchanged, only the anti-aging agent in Example 4 is removed to prepare the PU sole material.

Comparative Example 1

Preparation of PU sole material, the specific steps are as follows:

The remaining steps remained unchanged, except that the anti-aging agent in Example 4 was replaced by a compound of 0.2 parts of 2-(2,2,6,6-tetramethylpiperidin-4-yl)acetic acid, 0.3 parts of 2,6-di-tert-butylphenol and 0.3 parts of ultraviolet absorber UV-327 to prepare a PU sole material.

Performance Testing

The PU sole materials of Examples 2-4 and Comparative Examples 1-2 were subjected to an aging test at 100°C for 50 hours, and the tensile strength and elongation at break were measured. The specific data are shown in the following table:

It can be seen from the test results in the above table that, compared with the PU sole material of Comparative Example 2, the PU sole materials prepared in Examples 2-4 of the present invention have excellent aging resistance, and the anti-aging effect is more stable and lasting.

In the description of the specification, the description with reference to the terms "one embodiment", "example", "specific example", etc. means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic representation of the above terms does not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described can be combined in any one or more embodiments or examples in a suitable manner.

The above contents are merely examples and explanations of the present invention. Those skilled in the art may make various modifications or additions to the specific embodiments described or replace them in a similar manner. As long as they do not deviate from the invention or exceed the scope defined by the claims, they shall all fall within the protection scope of the present invention.

Claims (8)

1. The aging-resistant PU sole material is characterized by comprising the following raw materials in parts by weight: 80-100 parts of isocyanate, 70-80 parts of polyester polyol, 7-10 parts of chain extender, 0.5-1 part of foam stabilizer, 0.4-0.5 part of water, 0.6-1.2 parts of catalyst and 0.5-0.8 part of anti-aging agent;

wherein the anti-aging agent is prepared by the steps of:

S1, adding 4-amino-2, 6-di-tert-butylphenol and chloroform into a flask under the protection of nitrogen, stirring, adding glycidol, reacting for 4 hours at 60 ℃, cooling, distilling under reduced pressure, purifying by column chromatography, and distilling under reduced pressure to obtain an intermediate 1;

S2, adding the intermediate 1 and dimethyl sulfoxide into a flask under the protection of nitrogen, stirring, adding anhydrous sodium carbonate, adding 3-chloro-1, 2-propanediol, reacting at 80 ℃ for 3 hours, cooling, distilling under reduced pressure, washing and drying to obtain an intermediate 2;

S3, adding the intermediate 2, triethylamine and DMF into a flask under the protection of nitrogen, stirring, adding UV-327 and DMF, reacting at 80 ℃ for 8 hours, cooling, distilling under reduced pressure, washing and drying to obtain an intermediate 3;

s4, adding the intermediate 3, 2- (2, 6-tetramethyl piperidin-4-yl) acetic acid and DMF into a flask under the protection of nitrogen, stirring, adding concentrated sulfuric acid, reacting for 3 hours at 110 ℃, cooling, adding sodium bicarbonate solution, layering, drying, filtering, and distilling under reduced pressure to obtain the anti-aging agent.

2. The aging-resistant PU sole material according to claim 1, wherein the dosage ratio of 4-amino-2, 6-di-tert-butylphenol, glycidol and chloroform in the step S1 is 11.1g:3.5g:160mL; the dosage ratio of the intermediate 1, 3-chlorine-1, 2-propylene glycol, anhydrous sodium carbonate and dimethyl sulfoxide in the step S2 is 11.8g:3.7mL:9.3g:220mL; the dosage ratio of intermediate 2, UV-327, triethylamine and DMF in step S3 was 8.5g:8.6g:6.7mL:180mL; intermediate 3, 2- (2, 6-tetramethylpiperidin-4-yl) acetic acid, concentrated sulfuric acid and DMF in step S4 were used in a ratio of 14.5g:4.4g:1.3mL:200mL.

3. The aging-resistant PU sole material according to claim 1, wherein the isocyanate is one or more of polymethylene polyphenyl isocyanate, toluene diisocyanate and diphenylmethane diisocyanate.

4. The aging-resistant PU sole material according to claim 1, wherein the polyester polyol is a polyester polyol obtained by polycondensation of adipic acid and one of ethylene glycol, 1, 4-butanediol and 1, 6-hexanediol.

5. The aging-resistant PU sole material according to claim 1, wherein the chain extender is one or more of ethylene glycol, 1, 4-butanediol and glycerol.

6. The aging-resistant PU sole material of claim 1, wherein the foam stabilizer is polydimethylsiloxane.

7. The aging-resistant PU sole material according to claim 1, wherein the catalyst is one or more of triethanolamine, triethylenediamine and N, N-dimethylcyclohexylamine.

8. The method for preparing the aging-resistant PU sole material according to claim 1, comprising the following steps:

Weighing the raw materials according to the proportion, mixing the polyester polyol, the chain extender, the foam stabilizer and the catalyst for 1h at 75 ℃, then cooling to 40 ℃, adding water and the anti-aging agent, mixing for 1h, then adding the isocyanate, rapidly and uniformly stirring, pouring, curing and demolding to obtain the PU sole material.