Waterproof glue for leather shoes and preparation method thereof

Abstract

The present invention relates to the field of waterproof glue, and discloses a waterproof glue for leather shoes and a preparation method thereof. The raw materials of the waterproof glue include: by weight, 20 to 25 parts of butyl acrylate, 5 to 10 parts of acrylic acid, 10 to 15 parts of methyl methacrylate, 5 to 10 parts of hydroxyethyl acrylate, 5 to 10 parts of composite emulsifier, 5 to 8 parts of initiator, 0.5 to 1 part of catalyst, 40 to 65 parts of solvent, 7 to 21 parts of modifier solution, 0.1 to 0.5 parts of PAPU water repellent, and 5 to 8 parts of defoaming agent polyether L-65. Beneficial effects: (1) Epoxy acrylate resin with high impact strength, good chemical stability and strong water repellency is obtained by ring-opening esterification of epoxy resin and acrylic acid under the action of a catalyst. (2) By adding an emulsifier composed of sodium vinyl sulfonate and sodium dodecyl diphenyl ether disulfonate and a water repellent PAPU to the acrylic functional glue, the colloid stability is increased and the colloid is given excellent water repellency, and finally a waterproof glue for leather shoes is obtained.

Description

Technical Field

[0001] The invention relates to the field of waterproof glue and discloses waterproof glue for leather shoes and a preparation method thereof. Background Art

[0002] With the development of the times, the glue prepared and produced in the existing technology can no longer meet the needs of making leather shoes. The glue prepared by the existing process can only meet the simple bonding function and has poor waterproofness. When encountering bad weather such as rainy days, the soles of the shoes will seep into the soles and crack during use due to the insufficient waterproofness of the glue and the instability of the colloid, which reduces the durability and comfort of the shoes.

[0003] Existing processes for preparing waterproof adhesives often involve adding a single emulsifier to stabilize the colloid, followed by a water repellent to impart waterproofing. While these adhesives offer waterproofing, the stability of the single emulsifier and the lack of close interaction between the colloid and the water repellent can lead to debonding and water seepage after a period of use, resulting in poor durability. Therefore, optimization of the synthesis process and selection of appropriate emulsifiers are needed to achieve a more stable colloid while enhancing its water repellency.

[0004] In order to solve the above problems, it is of great significance to provide a waterproof glue for leather shoes. Summary of the Invention

[0005] The object of the present invention is to provide a method for preparing waterproof glue for leather shoes to solve the problems raised in the above background technology.

[0006] In order to solve the above technical problems, the present invention provides the following technical solutions:

[0007] A method for preparing waterproof glue for leather shoes, the preparation process of the waterproof glue for leather shoes comprising the following steps:

[0008] S1: Add acrylic acid monomer to a three-necked flask, heat to dissolve, then add emulsifier, solvent, and sodium bicarbonate, and stir and emulsify for 1 to 2 hours to obtain a pre-emulsion;

[0009] S2: Take the S1 pre-emulsion and divide it into two parts at a ratio of 1:3 to 1:5 to obtain a first pre-emulsion and a second pre-emulsion; add an initiator to each of the first pre-emulsion and the second pre-emulsion, mix them evenly, and obtain raw materials A and B;

[0010] Add raw material A to the reaction flask, add catalyst, heat to 40-60°C, react for 0.5-1 hour, add raw material B dropwise for 3-4 hours, add modifier solution dropwise for 0.5-1 hour, heat to 70-90°C, keep warm for 0.5-1 hour, cool by 30-45°C to obtain polymer emulsion;

[0011] S3: Cooling to 30-45°C, adding a water repellent and a defoaming agent, controlling the rotation speed to 500-1000 r / min, stirring for 6-10 minutes, and obtaining a waterproof glue for leather shoes.

[0012] More optimally, the raw materials for the waterproof glue for leather shoes include, by weight, 40-60 parts of acrylic monomer, 5-10 parts of emulsifier, 5-8 parts of initiator, 0.5-1 part of catalyst, 40-65 parts of solvent, 7-21 parts of modifier solution, 0.1-0.5 parts of water repellent, and 5-8 parts of defoamer. The defoamer is polyoxyethylene polyoxypropylene ether, model number polyether L-65.

[0013] More optimally, the acrylic monomers are butyl acrylate, acrylic acid, methyl methacrylate, and hydroxyethyl acrylate; the increase in the number of carbon atoms in the acrylic ester alkyl group increases the shielding effect on the polar group of the ester group, thereby improving water resistance. At the same time, due to the shielding effect, the intermolecular force is weakened, the internal plasticity is increased, and the brittle temperature is reduced. The acrylic ester-based glue has good water resistance and good stability.

[0014] More optimally, the emulsifier is sodium vinyl sulfonate and sodium dodecyl diphenyl ether disulfonate, and the ratio of the two is set to 3:1; in the scheme, the reactive and amphiphilic emulsifiers are combined to effectively enhance the emulsion stability and provide a prerequisite for subsequent uniform complexation with the water repellent; sodium dodecyl diphenyl ether disulfonate contains two negative charges per molecule and has a large dispersion force. The emulsifier obtained by compounding with sodium vinyl sulfonate has strong stability, which stabilizes the performance of the glue.

[0015] More optimally, the initiator is initiator APS (i.e. ammonium persulfate).

[0016] More optimally, the modifier is epoxy resin; epoxy resin has strong adhesion, good stability, and excellent electrical insulation performance, and when combined with acrylate, a glue that combines the advantages of both can be obtained.

[0017] More optimally, the modifier is EMEP-6801W waterborne epoxy resin; the epoxy resin and acrylic acid are subjected to ring-opening esterification under the action of a catalyst to obtain an epoxy acrylate resin with high impact strength, good chemical stability and strong water repellency.

[0018] More optimally, the catalyst is a triphenyl antimony catalyst; it has high catalytic activity, low product viscosity, and good stability of the catalytic product.

[0019] More optimally, the water repellent is PAPU, i.e., polyamide polyurea formaldehyde resin; the PAPU molecular chain contains two active functional groups, chloroethanol and polyamine. The chloroethanol group can form a chemical bond with the coating adhesive, while the polyamine group combines with the coating adhesive to form an ionic bond, cross-linking and curing to form a network-like cured film, giving the colloid strong waterproof properties; at the same time, the cationic nature of the PAPU water repellent can also synergize with the vinyl anions in the emulsifier sodium vinyl sulfonate, making the glue more stable and greatly enhancing the water repellency.

[0020] More optimally, sodium vinyl sulfonate and sodium dodecyl diphenyl ether disulfonate are compounded to obtain a composite emulsifier, and PAPU water repellent is added at the same time to obtain a stable waterproof glue for leather shoes with excellent water-repellent properties.

[0021] Compared with the prior art, the present invention has the following beneficial effects:

[0022] (1) The composition and content of the emulsifier were optimized, and a composite emulsifier of sodium vinyl sulfonate and sodium dodecyl diphenyl ether disulfonate was used in a ratio of 3:1, thereby effectively enhancing the emulsion stability and providing a prerequisite for subsequent uniform complexation with the water repellent;

[0023] (2) The anionic groups in the sodium vinyl sulfonate-sodium dodecyl diphenyl ether disulfonate composite emulsifier are used to form a complex with the cations in the water repellent PAPU, thereby synergistically improving the colloid stability while also improving its waterproof performance;

[0024] (3) The waterproof glue used for this type of leather shoes has high viscosity and excellent mechanical properties. The mechanical properties decrease slightly before and after immersion in water. It has good anti-aging and waterproof properties and has good practical performance. DETAILED DESCRIPTION

[0025] The following is a clear and complete description of the technical solutions in the embodiments of the present invention. Obviously, the embodiments described are only some embodiments of the present invention, not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making any creative efforts are within the scope of protection of the present invention.

[0026] The preparation process of waterproof glue for leather shoes includes the following chemicals: butyl acrylate CAS: 141-32-2; acrylic acid CAS: 79-10-7; methyl methacrylate CAS: 80-62-6; hydroxyethyl acrylate CAS: 818-61-1; sodium vinyl sulfonate CAS: 3039-83-6; sodium dodecyl diphenyl ether disulfonate CAS: 7575-62-4; sodium bicarbonate CAS: 144-55-8; ammonium persulfate initiator CAS: 7727-54-0; triphenyl antimony CAS: 603-36-1; EMEP-6801W water-based epoxy resin (epoxy equivalent weight 450-550 g / mol, Jiangsu Ou Mode Technology Co., Ltd.); defoamer polyether L-65 CAS: 9003-11-6; water repellent PAPU (model LWR-02, Wuxi Tianxin Chemical Co., Ltd.); polyacrylamide CPAM (Shanghai Jiejing Chemical Co., Ltd., molecular weight Mw 5,000,000-6,000,000); Potassium zirconium carbonate CAS: 23570-56-1 (Changzhou Chunli Trading Co., Ltd.);

[0027] The following parts are by mass, 1 part is 10g;

[0028] Example 1: S1: In a three-necked flask equipped with a thermometer, a stirrer, a reflux condenser, and a feeding device, 25 parts of butyl acrylate, 5 parts of acrylic acid, 15 parts of methyl methacrylate, and 8 parts of hydroxyethyl acrylate were added in sequence, and heated and stirred until dissolved; 6 parts of sodium vinyl sulfonate, 2 parts of sodium dodecyl diphenyl ether disulfonate, 30 parts of water, and 0.25 parts of sodium bicarbonate were added, and the stirring speed was set to 1000-1500 r / min, and high-speed stirring was performed for emulsification for 1 hour to obtain a pre-emulsion;

[0029] S2: Take 1 / 4 of the pre-emulsion, raise the reaction temperature to 45°C, add 2 parts of APS initiator dropwise for 1 hour; add 1 part of triphenyl antimony, then add the remaining pre-emulsion to the flask at one time, and add 4 parts of APS initiator dropwise for 4 hours; after the addition is complete, slowly add 14 parts of modifier solution (10 parts of deionized water and 4 parts of EMEP-6801W waterborne epoxy resin) dropwise 0.5 hours after the addition, raise the temperature to 70°C to initiate polymerization, and keep warm for 1 hour to obtain a polymer emulsion;

[0030] S3: After the temperature of the polymerized emulsion drops below 30°C, add 0.25 parts of PAPU as a water repellent and 6 parts of polyether L-65 as a defoaming agent, stir at a speed of 600 r / min for 8 minutes, and add 10 parts of deionized water to the resulting mixture to obtain waterproof glue for leather shoes.

[0031] Example 2 (the number of propylene monomers was changed, and the remaining steps were the same as in Example 1): S1: 20 parts of butyl acrylate, 10 parts of acrylic acid, 10 parts of methyl methacrylate, and 10 parts of hydroxyethyl acrylate were added sequentially to a three-necked flask equipped with a thermometer, a stirrer, a reflux condenser, and a feeding device, and heated and stirred until dissolved; 6 parts of sodium vinyl sulfonate, 2 parts of sodium dodecyl diphenyl ether disulfonate, 30 parts of water, and 0.25 parts of sodium bicarbonate were added, and the stirring speed was set to 1000-1500 r / min, and high-speed stirring was performed for 1 hour to obtain a pre-emulsion;

[0032] S2: Take 1 / 4 of the pre-emulsion, raise the reaction temperature to 45°C, add 2 parts of APS initiator dropwise for 1 hour; add 1 part of triphenyl antimony, then add the remaining pre-emulsion to the flask at one time, and add 4 parts of APS initiator dropwise for 4 hours; after the addition is complete, slowly add 14 parts of modifier solution (10 parts of deionized water and 4 parts of EMEP-6801W waterborne epoxy resin) dropwise 0.5 hours after the addition, raise the temperature to 70°C to initiate polymerization, and keep warm for 1 hour to obtain a polymer emulsion;

[0033] S3: After the temperature of the polymerized emulsion drops below 30°C, add 0.25 parts of PAPU as a water repellent and 6 parts of polyether L-65 as a defoaming agent, stir at a speed of 600 r / min for 8 minutes, and add 10 parts of deionized water to the resulting mixture to obtain waterproof glue for leather shoes.

[0034] Example 3 (changing the amount of initiator, the remaining steps are the same as Example 1): S1: In a three-necked flask equipped with a thermometer, a stirrer, a reflux condenser, and a charging device, 20 parts of butyl acrylate, 10 parts of acrylic acid, 10 parts of methyl methacrylate, and 10 parts of hydroxyethyl acrylate were added in sequence, and heated with stirring until dissolved; 6 parts of sodium vinyl sulfonate, 2 parts of sodium dodecyl diphenyl ether disulfonate, 30 parts of water, and 0.25 parts of sodium bicarbonate were added, and the stirring speed was set to 1000-1500 r / min, and emulsified with high-speed stirring for 1 hour to obtain a pre-emulsion;

[0035] S2: Take 1 / 4 of the pre-emulsion, raise the reaction temperature to 45°C, and add 3 parts of APS initiator dropwise for 1 hour; add 1 part of triphenyl antimony, then add the remaining pre-emulsion to the flask at one time, and add 3 parts of APS initiator dropwise for 4 hours; after the addition is complete, slowly add 14 parts of modifier solution (10 parts of deionized water and 4 parts of EMEP-6801W water-based epoxy resin) dropwise 0.5 hours after the addition, raise the temperature to 70°C to initiate polymerization, and keep warm for 1 hour to obtain a polymer emulsion;

[0036] S3: After the temperature of the polymerized emulsion drops below 30°C, add 0.25 parts of PAPU as a water repellent and 6 parts of polyether L-65 as a defoaming agent, stir at a speed of 600 r / min for 8 minutes, and add 10 parts of deionized water to the resulting mixture to obtain waterproof glue for leather shoes.

[0037] Comparative Example 1 (replacing 6 parts of sodium vinyl sulfonate emulsifier with 6 parts of sodium dodecyl diphenyl oxide disulfonate emulsifier, and the remaining steps are the same as in Example 1): S1: In a three-necked flask equipped with a thermometer, a stirrer, a reflux condenser, and a feeding device, 25 parts of butyl acrylate, 5 parts of acrylic acid, 15 parts of methyl methacrylate, and 8 parts of hydroxyethyl acrylate were added in sequence, and heated and stirred until dissolved; 8 parts of sodium dodecyl diphenyl oxide disulfonate, 30 parts of water, and 0.25 parts of sodium bicarbonate were added, and the stirring speed was set to 1000-1500 r / min, and high-speed stirring was performed for emulsification for 1 hour to obtain a pre-emulsion;

[0038] S2: Take 1 / 4 of the pre-emulsion, raise the reaction temperature to 45°C, add 2 parts of APS initiator dropwise for 1 hour; add 1 part of triphenyl antimony, then add the remaining pre-emulsion to the flask at one time, and add 4 parts of APS initiator dropwise for 4 hours; after the addition is complete, slowly add 14 parts of modifier solution (10 parts of deionized water and 4 parts of EMEP-6801W waterborne epoxy resin) dropwise 0.5 hours after the addition, raise the temperature to 70°C to initiate polymerization, and keep warm for 1 hour to obtain a polymer emulsion;

[0039] S3: After the temperature of the polymerized emulsion drops below 30°C, add 0.25 parts of PAPU as a water repellent and 6 parts of polyether L-65 as a defoaming agent, stir at a speed of 600 r / min for 8 minutes, and add 10 parts of deionized water to the resulting mixture to obtain waterproof glue for leather shoes.

[0040] Comparative Example 2 (replacing 6 parts of sodium vinyl sulfonate emulsifier with 6 parts of polyacrylamide CPAM emulsifier, and the remaining steps are the same as in Example 1): S1: In a three-necked flask equipped with a thermometer, a stirrer, a reflux condenser, and a feeding device, 25 parts of butyl acrylate, 5 parts of acrylic acid, 15 parts of methyl methacrylate, and 8 parts of hydroxyethyl acrylate were added in sequence, and heated and stirred until dissolved; 6 parts of polyacrylamide CPAM, 2 parts of sodium dodecyl diphenyl ether disulfonate, 30 parts of water, and 0.25 parts of sodium bicarbonate were added, and the stirring speed was set to 1000-1500 r / min, and high-speed stirring was performed for emulsification for 1 hour to obtain a pre-emulsion;

[0041] S2: Take 1 / 4 of the pre-emulsion, raise the reaction temperature to 45°C, add 2 parts of APS initiator dropwise for 1 hour; add 1 part of triphenyl antimony, then add the remaining pre-emulsion to the flask at one time, and add 4 parts of APS initiator dropwise for 4 hours; after the addition is complete, slowly add 14 parts of modifier solution (10 parts of deionized water and 4 parts of EMEP-6801W waterborne epoxy resin) dropwise 0.5 hours after the addition, raise the temperature to 70°C to initiate polymerization, and keep warm for 1 hour to obtain a polymer emulsion;

[0042] S3: After the temperature of the polymerized emulsion drops below 30°C, add 0.25 parts of PAPU as a water repellent and 6 parts of polyether L-65 as a defoaming agent, stir at a speed of 600 r / min for 8 minutes, and add 10 parts of deionized water to the resulting mixture to obtain waterproof glue for leather shoes.

[0043] Comparative Example 3 (0.25 parts of PAPU water repellent were replaced with 0.25 parts of potassium carbonate zirconium salt water repellent, and the other steps were the same as in Example 1): S1: 25 parts of butyl acrylate, 5 parts of acrylic acid, 15 parts of methyl methacrylate, and 8 parts of hydroxyethyl acrylate were added to a three-necked flask equipped with a thermometer, a stirrer, a reflux condenser, and a feeding device, and heated and stirred until dissolved; 6 parts of sodium vinyl sulfonate, 2 parts of sodium dodecyl diphenyl ether disulfonate, 30 parts of water, and 0.25 parts of sodium bicarbonate were added, and the stirring speed was set to 1000-1500 r / min, and high-speed stirring was stirred for 1 hour to obtain a pre-emulsion;

[0044] S2: Take 1 / 4 of the pre-emulsion, raise the reaction temperature to 45°C, add 2 parts of APS initiator dropwise for 1 hour; add 1 part of triphenyl antimony, then add the remaining pre-emulsion to the flask at one time, and add 4 parts of APS initiator dropwise for 4 hours; after the addition is complete, slowly add 14 parts of modifier solution (10 parts of deionized water and 4 parts of EMEP-6801W waterborne epoxy resin) dropwise 0.5 hours after the addition, raise the temperature to 70°C to initiate polymerization, and keep warm for 1 hour to obtain a polymer emulsion;

[0045] S3: When the temperature of the polymerized emulsion drops below 30°C, add 0.25 parts of potassium zirconium carbonate as a water repellent and 6 parts of defoaming agent polyether L-65, stir at a speed of 600 r / min for 8 minutes, and add 10 parts of deionized water to the resulting mixture to obtain waterproof glue for leather shoes.

[0046] Comparative Example 4 (the added composite emulsifier was replaced with 2 parts of sodium vinyl sulfonate and 6 parts of sodium dodecyl diphenyl oxide disulfonate, and the other steps were the same as in Example 1): S1: 25 parts of butyl acrylate, 5 parts of acrylic acid, 15 parts of methyl methacrylate, and 8 parts of hydroxyethyl acrylate were added to a three-necked flask equipped with a thermometer, a stirrer, a reflux condenser, and a feeding device, and heated and stirred until dissolved; 2 parts of sodium vinyl sulfonate, 6 parts of sodium dodecyl diphenyl oxide disulfonate, 30 parts of water, and 0.25 parts of sodium bicarbonate were added, and the stirring speed was set to 1000-1500 r / min, and high-speed stirring was performed for emulsification for 1 hour to obtain a pre-emulsion;

[0047] S2: Take 1 / 4 of the pre-emulsion, raise the reaction temperature to 45°C, add 2 parts of APS initiator dropwise for 1 hour; add 1 part of triphenyl antimony, then add the remaining pre-emulsion to the flask at one time, and add 4 parts of APS initiator dropwise for 4 hours; after the addition is complete, slowly add 14 parts of modifier solution (10 parts of deionized water and 4 parts of EMEP-6801W waterborne epoxy resin) dropwise 0.5 hours after the addition, raise the temperature to 70°C to initiate polymerization, and keep warm for 1 hour to obtain a polymer emulsion;

[0048] S3: After the temperature of the polymerized emulsion drops below 30°C, add 0.25 parts of PAPU as a water repellent and 6 parts of polyether L-65 as a defoaming agent, stir at a speed of 600 r / min for 8 minutes, and add 10 parts of deionized water to the resulting mixture to obtain waterproof glue for leather shoes.

[0049] Comparative Example 5 (modifier solution was not added, and the remaining steps were the same as in Example 1): S1: 25 parts of butyl acrylate, 5 parts of acrylic acid, 15 parts of methyl methacrylate, and 8 parts of hydroxyethyl acrylate were added sequentially to a three-necked flask equipped with a thermometer, a stirrer, a reflux condenser, and a feeding device, and heated and stirred until dissolved; 6 parts of sodium vinyl sulfonate, 2 parts of sodium dodecyl diphenyl ether disulfonate, 30 parts of water, and 0.25 parts of sodium bicarbonate were added, and the stirring speed was set to 1000-1500 r / min, and high-speed stirring was performed for emulsification for 1 hour to obtain a pre-emulsion;

[0050] S2: Take 1 / 4 of the pre-emulsion, raise the reaction temperature to 45°C, and add 2 parts of APS initiator dropwise for 1 hour; then add the remaining pre-emulsion to the flask at once, and add 4 parts of APS initiator dropwise for 4 hours; keep warm for 1 hour to obtain a polymer emulsion;

[0051] S3: After the temperature of the polymerized emulsion drops below 30°C, add 0.25 parts of PAPU as a water repellent and 6 parts of polyether L-65 as a defoaming agent, stir at a speed of 600 r / min for 8 minutes, and add 10 parts of deionized water to the resulting mixture to obtain waterproof glue for leather shoes.

[0052] Experiment: (1) The glue viscosity value test was carried out in accordance with the standard "Determination of viscosity value of adhesives" (GB / T2794-1995);

[0053] (2) Mechanical properties of glue before and after immersion in water: According to GB / T 528-2009 and GB / T 531-2008 standards, a universal tensile testing machine was used to measure the elongation at break and tensile strength of the glue before and after immersion in water. The data obtained are shown in the following table:

[0054] Table 1 Performance test data

[0055]

[0056] Conclusion: By comparing the data in Table 1, it can be seen that the amount of acrylic acid monomer used in the synthesis process affects the viscosity of the glue, but the impact is small. If epoxy resin is not added, the mechanical properties of the glue are significantly reduced and the viscosity also decreases slightly.

[0057] The changes in the type and proportion of emulsifiers have a great influence on the viscosity of the glue and the mechanical properties before and after immersion in water. This shows the importance of the correctly proportioned sodium vinyl sulfonate-sodium dodecyl diphenyl ether disulfonate composite emulsifier in the present invention.

[0058] The data shows that the use of a correctly proportioned sodium vinyl sulfonate-sodium dodecyl diphenyl ether disulfonate composite emulsifier and water repellent PAPU can significantly improve the viscosity of the glue and its mechanical properties before and after immersion in water, greatly improving its practical performance. It is a waterproof glue suitable for leather shoes.

[0059] Finally, it should be noted that the above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art will be able to modify the technical solutions described in the aforementioned embodiments or substitute equivalents for some of the technical features. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present invention shall be included within the scope of protection of the present invention.

Claims

1. A method for preparing waterproof glue for leather shoes, characterized in that: The preparation process of the waterproof glue for leather shoes comprises the following steps: S1: heating and dissolving acrylic acid monomer, adding emulsifier, solvent and sodium bicarbonate, stirring and emulsifying for 1-2 hours to obtain a pre-emulsion; S2: The pre-emulsion prepared in S1 is divided into two parts at a ratio of 1:3 to 1:5 to obtain a first pre-emulsion and a second pre-emulsion; an initiator is added to each of the first pre-emulsion and the second pre-emulsion, and the mixture is mixed to obtain raw materials A and B; Add catalyst to raw material A, heat to 40-60°C, react for 0.5-1 hour, add raw material B dropwise for 3-4 hours, add modifier solution dropwise for 0.5-1 hour, heat to 70-90°C, keep warm for 0.5-1 hour, cool to 30-45°C to obtain polymer emulsion; S3: Cool down to 30-45°C, add water repellent and defoaming agent, control the speed to 500-1000 r / min, and stir for 6-10 minutes to obtain waterproof glue; The raw materials of the waterproof glue for leather shoes include: by weight, 40-60 parts of acrylic monomer, 5-10 parts of emulsifier, 5-8 parts of initiator, 0.5-1 part of catalyst, 40-65 parts of solvent, 7-21 parts of modifier solution, 0.1-0.5 parts of water repellent, and 5-8 parts of defoaming agent; The emulsifier is a mixture of sodium vinyl sulfonate and sodium dodecyl diphenyl ether disulfonate, with a mass ratio of 3:

1. The water repellent is polyamide polyurea formaldehyde resin; the defoaming agent is polyoxyethylene polyoxypropylene ether; The modifier solution is composed of deionized water and EMEP-6801W waterborne epoxy resin, with a mass ratio of 5:2; The raw materials of the acrylic acid monomer include: 20-25 parts of butyl acrylate, 5-10 parts of acrylic acid, 10-15 parts of methyl methacrylate, and 5-10 parts of hydroxyethyl acrylate, in parts by weight.

2. The waterproof glue prepared by the method for preparing waterproof glue for leather shoes according to claim 1.

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