Damp-proof using method of polymethacrylate pressure-sensitive adhesive

Abstract

The invention relates to a damp-proof using method of a polymethacrylate pressure-sensitive adhesive. The method comprises steps as follows: Step 1) evenly mixing a solvent type polymethacrylate pressure-sensitive adhesive and a solvent to prepare an adhesive diluent; Step 2) evenly mixing a solvent and a water removing agent with the mass accounting for 0.5%-5% of the dry weight of the solvent type polymethacrylate pressure-sensitive adhesive, and adding the mixture to the adhesive diluent; Step 3) evenly mixing a solvent and a water removing agent catalyst with the mass accounting for 5%-50% of the pure mass of the water removing agent, and adding the mixture to the adhesive diluent; Step 4) evenly mixing a catalyst of an isocyanate curing agent and a solvent, and adding the mixture to the adhesive diluent; Step 5) evenly mixing the isocyanate curing agent and a solvent, and adding the mixture to the adhesive diluent to obtain a polymethacrylate adhesive coating liquid; Step 6) coating the surface of a base material with the adhesive coating liquid, and performing desolvation, curing and post-curing in a drying oven to obtain the polymethacrylate adhesive product.

Description

technical field [0001] The invention relates to the field of pressure-sensitive adhesive products, in particular to a low-cost method for using a solvent-based polymethacrylate adhesive used in a humid environment. Background technique [0002] Pressure-sensitive adhesive products can exhibit viscosity without heating or using solvents, and are widely used in die-cutting, electronics, medicine, optics, electroplating protection, and material processing. Among them, solvent-based polymethacrylate adhesives have expanded the scope and field of use due to their excellent bonding performance, good electrical performance, excellent weather resistance, convenient preparation, and good economy. [0003] Polymethacrylate adhesives widely use isocyanate curing agents. The advantage of isocyanate curing agent is good curing performance and fast curing speed, but it is easily affected by moisture in the environment. The moisture remaining in the adhesive solvent and in the air will p...

AI Technical Summary

Problems solved by technology

The advantage of isocyanate curing agent is good curing performance and fast curing speed, but it is easily affected by moisture in the environment

The moisture remaining in the adhesive solvent and in the air will preferentially react with isocyanate and release carbon dioxide gas, which will cause the surface of the coated adhesive product to appear cloudy or rough; when the air humidity is relatively high, the air will The moisture in the solvent is more likely to enter the solvent. After reacting with the isocyanate curing agent, the generated carbon dioxide gas forms pinhole-like pores (commonly known as "needle holes") or bubbles (commonly known as "prickly heat") on the rubber surface, which seriously affects the adhesion. The surface quality of the product may lead to the scrapping of the product; at the same time, because the moisture in the environment consumes a certain amount of isocyanate curing agent, the curing of the adhesive product is not complete, resulting in an abnormal increase in the viscosity of the adhesive product, a decrease in cohesion, and a temperature resistance. Insufficient weather resistance and residual glue and degumming phenomenon

[0004] In view of the side effects of moisture in the environment on isocyanate curing agents, solvent-based polymethacrylate adhesive coating factories generally take measures to stop production in hot and humid weather to avoid losses, or add isocyanate to the coating solution. Polar solvents such as propanol to disperse the water and gather in the coating agent. Although this can partially reduce the occurrence of bad phenomena such as rough rubber surface, it is still difficult to avoid the haze of the rubber surface, and the remaining water and The hydroxyl groups on the chemical structure of alcohol solvents will also react with the isocyanate curing agent, resulting in unnecessary loss of curing agent, which will still lead to incomplete cross-linking and curing of adhesive products, inconsistent viscosity, poor stickiness and poor temperature resistance The adverse effects of intrinsic properties such as

If cooling and dehumidification in the coating workshop is used to improve the moisture content in the air, but on the one hand, the low temperature and dehumidification will cause an increase in energy consumption costs, and on the other hand, the dry coating environment will also cause static electricity in the coating station. Accumulative increase leads to fire accidents

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