An aqueous chloroprene rubber and its preparation method

Abstract

The present invention belongs to the technical field of adhesives, and discloses an aqueous neoprene adhesive and a preparation method thereof. The aqueous neoprene adhesive is prepared from the following components in parts by weight: 30-60 parts of neoprene latex, 5-20 parts of methyl methacrylate, 1-10 parts of lithium silicate, 0.2-1.5 parts of water-soluble chitosan, 1-5 parts of redox initiator, 1-10 parts of emulsifier and deionized water; the solid content of the aqueous neoprene adhesive is 10-40%. When used as an adhesive, the aqueous neoprene adhesive of the present invention has excellent heat resistance and T-peel strength, and has high product value and good market application prospects.

Description

Technical Field

[0001] The present invention relates to the technical field of adhesives, and particularly relates to an aqueous neoprene adhesive and a preparation method thereof. Background Art

[0002] Neoprene adhesives are prepared by formulating neoprene latex with fillers, vulcanizing agents, anti-aging agents, solvents and other compounding agents; neoprene latex adhesives are mainly used for bonding rubber to metal, rubber to rubber, and are also widely used for bonding materials such as fabrics, leathers, plastics, woods, and glasses.

[0003] Neoprene rubber adhesives can be divided into three categories according to their dispersion media: solvent-based, water-emulsion and solvent-free; currently, the most widely used in the market is solvent-based neoprene adhesives.

[0004] With the increasing emphasis on environmental protection and safety by people, aqueous neoprene adhesives have gradually received attention and favor in the market; compared with solvent-based neoprene adhesives, aqueous neoprene adhesives have high safety, are not prone to fire, have small odor, cause little environmental pollution during use, are easy to adjust viscosity and concentration, are easy to operate, have good adhesion performance, and do not have problems such as easy wire drawing that solvent-based adhesives are prone to.

[0005] However, aqueous neoprene adhesives mainly have the following deficiencies: the initial adhesion strength of aqueous neoprene adhesives is not as high as that of solvent-based neoprene adhesives, the drying speed is slow, and the heat resistance of the adhesive layer is not ideal; above 50°C, the cohesion will be significantly weakened due to the dissolution of crystallization, and when the temperature exceeds 70°C, its bonding performance will decline, and it cannot be applied to high-temperature scenarios.

[0006] To solve the above problems, the modification of aqueous neoprene latex is the only way for it to enter the commercial market; to improve the heat resistance of aqueous neoprene adhesives, researchers have used methods such as carboxylated neoprene rubber, chelating resin, cross-linking agent, heat vulcanization accelerator, polyurethane with terminal isocyanate group, and silane coupling agent to appropriately increase the cross-linking degree of the polymer chain, thereby improving the heat resistance performance.

[0007] Chinese Patent No. 201210311125.7 discloses a preparation method of a heat-resistant modified aqueous neoprene adhesive, which uses vinyl monomers to modify and graft neoprene latex, so that the modified aqueous neoprene adhesive can withstand a high temperature of 120°C, and has strong definite elongation stress and tensile strength, good wear resistance, flexure crack resistance, aging resistance, solvent resistance and mechanical properties, and has a very high bonding strength.

[0008] The Chinese patent 202011233341.5 previously applied for by the present applicant also discloses a method for preparing a heat-resistant chloroprene latex adhesive by grafting modification on chloroprene latex. The raw material composition is as follows: modified heat-resistant chloroprene latex, chloroprene latex, styrene-acrylate emulsion, tackifying emulsion, metal oxide aqueous solution, antioxidant aqueous solution, thickener and coagulant. Among them, by weight, it includes the following components: 30-60 parts of modified heat-resistant chloroprene latex, 30-60 parts of chloroprene latex, 100 parts of styrene-acrylate emulsion, 5-15 parts of tackifying emulsion, 0.2-0.6 parts of metal oxide aqueous solution, 0.2-0.6 parts of antioxidant aqueous solution, 0.3-0.8 parts of thickener and 1-3 parts of coagulant; the heat-resistant chloroprene latex adhesive and its preparation method successfully grafted two monomers, methyl methacrylate and octavinyl-POSS, on chloroprene latex through emulsion polymerization. The heat resistance and storage stability of the latex-type chloroprene adhesive prepared using the modified chloroprene latex have been effectively improved, which is beneficial to improving the transportation and storage capabilities of the adhesive product and has good economic benefits.

[0009] The above patents all modify chloroprene latex by chemical grafting. Although the heat resistance and performance of chloroprene latex are enhanced to a certain extent after modification, simply searching for new modified chloroprene latex through continuous experiments of chemical grafting is a relatively narrow technical development direction. Based on the diverse production requirements and multi-directional development of technological progress, finding a method to modify and improve the heat resistance and mechanical properties of aqueous chloroprene latex through physical blending, and preparing an aqueous chloroprene with high heat resistance and good mechanical properties is another relatively promising direction. Summary of the Invention

[0010] One of the purposes of the present invention is to provide an aqueous chloroprene rubber, which has excellent heat resistance and T-peel strength when used as an adhesive, has high product value and good market application prospects.

[0011] Another purpose of the present invention is to provide a preparation method of an aqueous chloroprene rubber, which improves the heat resistance and mechanical properties of the aqueous chloroprene rubber through physical blending, and effectively solves the problem of unsatisfactory heat resistance of the aqueous chloroprene rubber layer.

[0012] At the same time, the present invention also provides another further improved aqueous chloroprene rubber, which is mixed with styrene-acrylate emulsion on the basis of the above aqueous chloroprene rubber, not only improves the performance of the aqueous chloroprene rubber, but also improves the storage stability of the aqueous chloroprene rubber.

[0013] Similarly, the present invention also provides a preparation method of the above aqueous chloroprene rubber, which effectively solves the problem of the compatibility and stability of styrene-acrylate emulsion and chloroprene latex through physical blending, and further enhances the performance and storage stability of the aqueous chloroprene rubber.

[0014] To achieve the above object, the present invention provides a water-based chloroprene rubber, which is prepared by using the following components in parts by weight:

[0015] 30-60 parts of chloroprene rubber latex, 5-20 parts of methyl methacrylate, 1-10 parts of lithium silicate, 0.2-1.5 parts of water-soluble chitosan, 1-5 parts of redox initiator, 1-10 parts of emulsifier and deionized water; the solid content of the water-based chloroprene rubber is 10-40%.

[0016] Preferably, the water-soluble chitosan is one or both of carboxymethyl chitosan and hydroxypropyl chitosan.

[0017] Preferably, the emulsifier is one or more of sodium dodecyl sulfate, sodium dodecylbenzene sulfonate, and sodium dodecyl diphenyl ether sulfonate.

[0018] Preferably, the redox initiator is one or more of tert-butyl hydroperoxide-tetraethylenepentamine, potassium persulfate-sodium bisulfite, and cumene hydroperoxide-tetraethylenepentamine.

[0019] The present invention also provides another water-based chloroprene rubber, which comprises the following components in parts by weight:

[0020] 30-60 parts of chloroprene rubber latex, 5-20 parts of methyl methacrylate, 1-10 parts of lithium silicate, 0.2-1.5 parts of water-soluble chitosan, 1-5 parts of redox initiator, 1-10 parts of emulsifier, 50-100 parts of deionized water, and 5-15 parts of styrene-acrylic emulsion.

[0021] Preferably, the water-soluble chitosan is one or both of carboxymethyl chitosan and hydroxypropyl chitosan.

[0022] Preferably, the emulsifier is one or more of sodium dodecyl sulfate, sodium dodecylbenzene sulfonate, and sodium dodecyl diphenyl ether sulfonate.

[0023] Preferably, the redox initiator is one or more of tert-butyl hydroperoxide-tetraethylenepentamine, potassium persulfate-sodium bisulfite, and cumene hydroperoxide-tetraethylenepentamine.

[0024] The present invention also provides a method for preparing water-based chloroprene rubber, comprising the following steps:

[0025] Step 1: Stir and mix lithium silicate and deionized water to make the lithium silicate completely dispersed and expanded in the system, then add an emulsifier and continue stirring for 0.5-1h to obtain a solution;

[0026] Step 2: Cool down the solution obtained in Step 1, add chloroprene latex and water-soluble chitosan, stir, dilute with deionized water, then uniformly dropwise add a mixture of methyl methacrylate and an oxidation initiator within 100 min, simultaneously dropwise add a reducing initiator, carry out a constant-temperature reaction for 3.5 - 4 h, and cool to obtain the aqueous chloroprene rubber adhesive.

[0027] Preferably, the stirring temperature in Step 1 is 70°C, and the amount of deionized water used is controlled such that the total system solid content is 9 - 11%.

[0028] Specifically preferably, the amount of deionized water used is controlled such that the total system solid content is 10%.

[0029] Further preferably, in Step 2, the solution obtained in Step 1 is cooled to 50°C, after adding chloroprene latex, carry out constant-temperature stirring at 50°C, and dilute with deionized water to a solid content of 10 - 30%.

[0030] As a specific preferred scheme, when adding deionized water for dilution in Step 2, the total system solid content can be selected as 10%, 15%, 20%, 25%, 30%.

[0031] The present invention also provides another preparation method of aqueous chloroprene rubber, including the following steps:

[0032] Step 1: Stir and mix lithium silicate with deionized water, after lithium silicate is completely dispersed and swollen in the system, add an emulsifier, and continue stirring for 0.5 - 1 h to obtain a solution;

[0033] Step 2: After the solution obtained in Step 1 is cooled, add styrene-acrylic emulsion and stir, then dilute with deionized water;

[0034] Step 3: Heat up the solution obtained in Step 2, add chloroprene latex and water-soluble chitosan and stir, dilute with deionized water, then uniformly dropwise add a mixture of methyl methacrylate and an oxidation initiator within 100 min, simultaneously dropwise add a reducing initiator, carry out a constant-temperature reaction for 3.5 - 4 h, and cool to obtain the aqueous chloroprene rubber adhesive.

[0035] Preferably, the stirring temperature in Step 1 is 70°C, and the stirring and mixing of lithium silicate and deionized water controls the total system to be 9 - 11%;

[0036] Preferably, in Step 2, the solution obtained in Step 1 is cooled to 25 - 30°C, after adding styrene-acrylic emulsion, carry out constant-temperature stirring at 25 - 30°C, and dilute with deionized water to a solid content of 10 - 18%;

[0037] Preferably, the solution obtained in step 2 of step 3 is cooled to 50°C, chloroprene latex is added, and the mixture is stirred at a constant temperature of 50°C, and then deionized water is added to dilute the solid content to 10-30%.

[0038] Advantages

[0039] Compared with the prior art, the present invention has at least the following advantages:

[0040] (1) The present invention provides an aqueous chloroprene rubber, which improves the heat resistance of the aqueous chloroprene rubber by the physical blending method of lithium silicate, and the water-soluble chitosan further strengthens the network structure of lithium silicate, resulting in a synergistic effect to improve the mechanical properties of the aqueous chloroprene rubber, especially a large improvement in the T-peel strength of the aqueous chloroprene rubber;

[0041] (2) The present invention provides another aqueous chloroprene rubber. Compared with silicates such as sodium silicate and potassium silicate, this component combination can effectively play the role of lithium silicate, and solves the problem that styrene-acrylic emulsion is not compatible with lithium silicate and cannot improve the bonding strength of the adhesive;

[0042] (3) The present invention provides another aqueous chloroprene rubber. Through the strengthened network structure of lithium silicate and water-soluble chitosan, the blending stability of styrene-acrylic emulsion and chloroprene latex is improved, and the storage stability and mechanical properties of the aqueous chloroprene rubber are effectively improved. Specific Embodiments

[0043] The following is a further description of the present invention in conjunction with embodiments, but it does not constitute any limitation to the present invention. Any limited modifications made within the scope of the claims of the present invention are still within the scope of the claims of the present invention.

[0044] In order to explain the technical content of the present invention in detail, the following further description is made in conjunction with the embodiments.

[0045] It should be noted that the chloroprene latex used in the following examples is a common raw material for those skilled in the art, and the solid content of the emulsion is 52-58%; the lithium silicate is purchased from Zhengzhou Zhongning Chemical Products Co., Ltd. and is configured into a 20-40% aqueous solution when used; the carboxymethyl chitosan and hydroxypropyl chitosan are both purchased from Nantong Green God Biotechnology Co., Ltd.

[0046] Example 1

[0047] An aqueous chloroprene rubber is prepared by the following steps:

[0048] Step 1: Calculated by weight, 1 part of lithium silicate is added, and an appropriate amount of deionized water is used to control the solid content of the total system to 10%. Under the condition of 70°C, the mixture is stirred at a constant temperature to completely disperse and expand lithium silicate in the system, and then 1 part of emulsifier is added, and stirring is continued for 0.5 h to obtain a solution;

[0049] Step 2: Cool the solution obtained in Step 1 to 50°C, then add 30 parts of chloroprene latex and 0.2 part of carboxymethyl chitosan, and carry out constant-temperature stirring at 50°C. Add deionized water to dilute to a solid content of 10%, and then uniformly dropwise add a mixed solution containing 5 parts of methyl methacrylate and 1 part of tert-butyl hydroperoxide within 100 min. At the same time, dropwise add 1 part of tetraethylenepentamine, keep the temperature constant for 3.5 h, and cool to room temperature to obtain the aqueous chloroprene rubber.

[0050] Example 2

[0051] An aqueous chloroprene rubber is prepared by the following steps:

[0052] Step 1: By weight, add 5 parts of lithium silicate, and use an appropriate amount of deionized water to control the solid content of the total system to 10%. Carry out constant-temperature stirring at 70°C to completely disperse and expand lithium silicate in the system, then add 5 parts of emulsifier, and continue stirring for 0.5 h to obtain a solution;

[0053] Step 2: Cool the solution obtained in Step 1 to 50°C, then add 40 parts of chloroprene latex and 1 part of carboxymethyl chitosan, and carry out constant-temperature stirring at 50°C. Add deionized water to dilute to a solid content of 20%, and then uniformly dropwise add a mixed solution containing 15 parts of methyl methacrylate and 3 parts of tert-butyl hydroperoxide within 100 min. At the same time, dropwise add 3 parts of tetraethylenepentamine, keep the temperature constant for 3.5 h, and cool to room temperature to obtain the aqueous chloroprene rubber.

[0054] Example 3

[0055] An aqueous chloroprene rubber is prepared by the following steps:

[0056] Step 1: By weight, add 10 parts of lithium silicate, and use an appropriate amount of deionized water to control the solid content of the total system to 10%. Carry out constant-temperature stirring at 70°C to completely disperse and expand lithium silicate in the system, then add 10 parts of emulsifier, and continue stirring for 1 h to obtain a solution;

[0057] Step 2: Cool the solution obtained in Step 1 to 50°C, then add 60 parts of chloroprene latex and 1.5 parts of hydroxypropyl chitosan, and carry out constant-temperature stirring at 50°C. Add deionized water to dilute to a solid content of 30%, and then uniformly dropwise add a mixed solution containing 20 parts of methyl methacrylate and 5 parts of tert-butyl hydroperoxide within 100 min. At the same time, dropwise add 5 parts of tetraethylenepentamine, keep the temperature constant for 3.5 h, and cool to room temperature to obtain the aqueous chloroprene rubber.

[0058] Example 4

[0059] An aqueous chloroprene rubber is prepared by the following steps:

[0060] Step 1: By weight, add 1 part of lithium silicate, and add an appropriate amount of deionized water to control the solid content of the total system to be 10%. Stir at a constant temperature of 70 °C to completely disperse and expand the lithium silicate in the system. Then add 1 part of emulsifier and continue stirring for 0.5 h to obtain a solution;

[0061] Step 2: After the solution obtained in Step 1 is cooled to 25 °C, add 5 parts of styrene-acrylic emulsion and stir at 25 °C. Add deionized water to dilute to a solid content of 10% to obtain a solution;

[0062] Step 3: Heat the solution obtained in Step 2 to 50 °C, then add 30 parts of chloroprene latex and 0.2 part of carboxymethyl chitosan, and stir at a constant temperature of 50 °C. Add deionized water to dilute to a solid content of 10%, and then uniformly dropwise add a mixed solution containing 5 parts of methyl methacrylate and 1 part of tert-butyl hydroperoxide within 100 min. At the same time, dropwise add 1 part of tetraethylenepentamine, keep the temperature constant for 3.5 h, and cool to room temperature to obtain the aqueous chloroprene glue.

[0063] Example 5

[0064] An aqueous chloroprene glue is prepared through the following steps:

[0065] Step 1: By weight, add 5 parts of lithium silicate, and add an appropriate amount of deionized water to control the solid content of the total system to be 10%. Stir at a constant temperature of 70 °C to completely disperse and expand the lithium silicate in the system. Then add 5 parts of emulsifier and continue stirring for 0.5 h to obtain a solution;

[0066] Step 2: After the solution obtained in Step 1 is cooled to 25 °C, add 10 parts of styrene-acrylic emulsion and stir at 25 °C. Add deionized water to dilute to a solid content of 13% to obtain a solution;

[0067] Step 3: Heat the solution obtained in Step 2 to 50 °C, then add 40 parts of chloroprene latex and 1 part of carboxymethyl chitosan, and stir at a constant temperature of 50 °C. Add deionized water to dilute to a solid content of 20%, and then uniformly dropwise add a mixed solution containing 15 parts of methyl methacrylate and 3 parts of tert-butyl hydroperoxide within 100 min. At the same time, dropwise add 3 parts of tetraethylenepentamine, keep the temperature constant for 3.5 h, and cool to room temperature to obtain the aqueous chloroprene glue.

[0068] Example 6

[0069] An aqueous chloroprene glue is prepared through the following steps:

[0070] Step 1: By weight, add 10 parts of lithium silicate, and add an appropriate amount of deionized water to control the solid content of the total system to be 10%. Stir at a constant temperature of 70 °C to completely disperse and expand the lithium silicate in the system. Then add 10 parts of emulsifier and continue stirring for 1 h to obtain a solution;

[0071] Step 2: After the solution obtained in Step 1 is cooled to 30°C, add 15 parts of styrene-acrylic emulsion and stir at 30°C, then add deionized water to dilute to a solid content of 18% to obtain a solution;

[0072] Step 3: Heat the solution obtained in Step 2 to 50°C, then add 60 parts of chloroprene latex and 1.5 parts of hydroxypropyl chitosan, and carry out constant-temperature stirring at 50°C. Add deionized water to dilute to a solid content of 30%, and then uniformly dropwise add a mixed solution containing 20 parts of methyl methacrylate and 5 parts of tert-butyl hydroperoxide within 100 min. At the same time, dropwise add 5 parts of tetraethylenepentamine, keep the temperature constant for 3.5 h, and cool to room temperature to obtain the aqueous chloroprene rubber.

[0073] Comparative Example 1

[0074] It is generally the same as Example 1, except that the dosage of lithium silicate is 0.5 part.

[0075] Comparative Example 2

[0076] It is generally the same as Example 3, except that the dosage of lithium silicate is 12 parts.

[0077] Comparative Example 3

[0078] It is generally the same as Example 2, except that the dosage of carboxymethyl chitosan is 0.1 part.

[0079] Comparative Example 4

[0080] It is generally the same as Example 2, except that the dosage of carboxymethyl chitosan is 2 parts.

[0081] Comparative Example 5

[0082] It is generally the same as Example 2, except that the carboxymethyl chitosan is replaced with water-insoluble chitosan.

[0083] Comparative Example 6

[0084] It is generally the same as Example 2, except that water-soluble chitosan is not used.

[0085] Comparative Example 7

[0086] It is generally the same as Example 6, except that the lithium silicate is replaced with potassium silicate with similar modulus and pH value.

[0087] Application Implementation

[0088] The aqueous chloroprene rubbers obtained in Examples 1-6 and Comparative Examples 1-7 are configured one by one according to the formula in Table 1 to obtain the chloroprene adhesives of Application Examples 1-6 and Comparative Application Examples 1-7;

[0089] Table 1 - Formulation Table of Chloroprene Adhesives for Application Examples 1 - 6 and Comparative Examples 1 - 7 (by weight parts)

[0090]

[0091] Performance Test

[0092] The chloroprene rubber adhesives prepared from Application Examples 1 - 6 and Comparative Examples 1 - 7 were subjected to performance tests, and the test results are shown in Table 2;

[0093] Table 2 - Performance Test Results of Application Examples 1 - 6 and Comparative Examples 1 - 7

[0094]

[0095] It can be seen from the data in Table 2 that:

[0096] From the comparison of the performance data of Application Example 1 and Comparative Example 1, and Application Example 3 and Comparative Example 2, it can be seen that the dosage of lithium silicate plays a relatively key role in the technical solution of the present invention. Excessive or insufficient dosage of lithium silicate will affect the mechanical properties and heat resistance of the water - based chloroprene rubber;

[0097] From the comparison between Application Example 2 and Comparative Examples 3 - 6, it can be seen that there is a synergistic effect between water - soluble chitosan and lithium silicate to increase the mechanical properties of the water - based chloroprene rubber. The content of water - soluble chitosan has little effect on the heat resistance of the water - based chloroprene rubber. However, compared with Comparative Examples 5 and 6 using non - water - soluble chitosan and without using chitosan, the technical solution using water - soluble chitosan still effectively increases the heat resistance of the water - based chloroprene rubber;

[0098] From the comparison of the data of Application Example 6 and Comparative Example 7, it can be seen that under the synergistic effect of lithium silicate and water - soluble chitosan in the present invention, even if styrene - acrylic emulsion that does not match well with lithium silicate is added, the mechanical properties and heat resistance of the water - based chloroprene rubber can be effectively improved; there is no synergistic effect between potassium silicate and water - soluble chitosan, and the improvement of the mechanical properties of the water - based chloroprene rubber is not significant.

[0099] The embodiments presented herein are only selected embodiments according to all possible combinations of embodiments. The appended claims should not be limited by the embodiments illustrating the present invention. Some numerical ranges used in the claims include sub - ranges within them, and variations within these ranges should also be covered by the appended claims.

Claims

1. An aqueous chloroprene rubber, characterized in that, it is prepared from the following components in parts by weight: 30 - 60 parts of chloroprene latex, 5 - 20 parts of methyl methacrylate, 1 - 10 parts of lithium silicate, 0.2 - 1.5 parts of water-soluble chitosan, 1 - 5 parts of redox initiator, 1 - 10 parts of emulsifier and deionized water; the solid content of the aqueous chloroprene rubber is 10 - 40%.

2. The aqueous chloroprene rubber according to claim 1, characterized in that, the water-soluble chitosan is one or both of carboxymethyl chitosan and hydroxypropyl chitosan.

3. The aqueous chloroprene rubber according to claim 1, characterized in that, it further comprises 5 - 15 parts of styrene-acrylic emulsion.

4. The aqueous chloroprene rubber according to any one of claims 1 - 3, characterized in that, the emulsifier is one or more of sodium dodecyl sulfate, sodium dodecylbenzenesulfonate, and sodium dodecyl diphenyl ether sulfonate.

5. The aqueous chloroprene rubber according to any one of claims 1 - 3, characterized in that, the redox initiator is one or more of tert-butyl hydroperoxide - tetraethylenepentamine, potassium persulfate - sodium bisulfite, and cumene hydroperoxide - tetraethylenepentamine.

6. A preparation method of the aqueous chloroprene rubber according to any one of claims 1, 2, 4, and 5, characterized in that, it comprises the following steps: Step 1: Stir and mix lithium silicate with deionized water. After lithium silicate is completely dispersed and swollen in the system, add the emulsifier and continue stirring for 0.5 - 1 h to obtain a solution; Step 2: Cool the solution obtained in Step 1, then add chloroprene latex and water-soluble chitosan and stir. Add deionized water for dilution, and then uniformly dropwise add a mixture of methyl methacrylate and oxidation initiator within 100 min, while dropwise adding a reduction initiator, and carry out a constant-temperature reaction for 3.5 - 4 h. After cooling, the aqueous chloroprene rubber adhesive is obtained.

7. The preparation method of the aqueous chloroprene rubber according to claim 6, characterized in that, the stirring temperature in Step 1 is 70 °C, and the dosage of deionized water is controlled so that the total system solid content is 9 - 11%.

8. The preparation method of the aqueous chloroprene rubber according to claim 6, characterized in that, in Step 2, the solution obtained in Step 1 is cooled to 50 °C, and after adding chloroprene latex, carry out constant-temperature stirring at 50 °C, and add deionized water for dilution to a solid content of 10 - 30%.

9. The preparation method of the aqueous chloroprene rubber according to claim 3, characterized in that, it comprises the following steps: Step 1: Stir and mix lithium silicate with deionized water. After lithium silicate is completely dispersed and swollen in the system, add the emulsifier and continue stirring for 0.5 - 1 h to obtain a solution; Step 2: After the solution obtained in Step 1 is cooled, add styrene-acrylic emulsion and stir, and add deionized water for dilution; Step 3: Heat up the solution obtained in Step 2, then add chloroprene latex and water-soluble chitosan and stir. Add deionized water for dilution, and then uniformly dropwise add a mixture of methyl methacrylate and oxidation initiator within 100 min, while dropwise adding a reduction initiator, and carry out a constant-temperature reaction for 3.5 - 4 h. After cooling, the aqueous chloroprene rubber adhesive is obtained.

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