Novel method for preparing crylic acid modified resin for two-component waterborne polyurethane adhesive

Abstract

The invention belongs to the field of adhesives, and discloses a novel method for preparing crylic acid modified resin for a two-component waterborne polyurethane adhesive. The novel method comprises the following steps: directly selecting polymer resin or synthesizing polymer resin from raw materials, adding a solvent into the polymer resin or synthesizing polymer resin from raw material, thereby modifying by using vinyl or crylic acid and an ester monomer at certain temperature or in the presence of an initiator, and further implementing a reaction on organic amino and acid substances, thereby obtaining the crylic acid modified resin for the two-component waterborne polyurethane adhesive. By adopting the method, crylic acid modified resin can be prepared, and can be directly used or is combined with a component containing isocyanate to obtain a polyurethane adhesive after chain expansion, the isocyanate group in the adhesive can be preferably reacted with active groups of resin in a waterborne environment, and can stably exist in the waterborne environment; in addition, compared with a solvent type polyurethane adhesive, the adhesive is relatively low in VOC content, the defects that an ordinary waterborne polyurethane adhesive can be stripped from a substrate, has bubbles in an adhesive film, is poor in adhesion and has material defects after being used can be avoided, and the cost of the polyurethane adhesive can be lowered.

Description

technical field [0001] The invention relates to a preparation method of an acrylic modified resin for a novel water-based two-component polyurethane adhesive, belonging to the field of adhesives. Background technique [0002] Polyurethane adhesives refer to adhesives containing urethane bonds or isocyanate groups in the base material molecule. Polyurethane adhesives contain highly polar and chemically active isocyanate groups and urethane groups, which are compatible with materials containing active hydrogen, porous materials such as wood, leather, paper, ceramics, and smooth surfaces such as metals, glass, rubber, and plastics. The materials have excellent chemical adhesion, and the bond is firm. Because the isocyanate group is very active, it can react with compounds containing active hydrogen such as alcohols, acids, amines and water, and react according to a certain equivalent. The reaction between isocyanate and water generates carbon dioxide, resulting in the loss of ...

AI Technical Summary

Problems solved by technology

Because the isocyanate group is very active, it can react with compounds containing active hydrogen such as alcohols, acids, amines and water, and react according to a certain equivalent. The reaction between isocyanate and water generates carbon dioxide, resulting in the loss of isocyanate, which leads to The reduction of the reacted isocyanate in the material or the adhesive base material will result in a decrease in bonding performance or even failure. Therefore, the various raw materials and diluents of general-purpose polyurethane adhesives must strictly control moisture and substances containing active hydrogen such as alcohols and amines. As well as the content of phenols, in high humidity weather such as the rainy season in the south, it will often cause large fluctuations in bonding performance, resulting in unnecessary losses

[0003] At present, the polyurethane adhesives used in China are mainly solvent-based two-component polyurethane adhesives, which contain a large amount of esters, ketones, benzenes and free isocyanates, which are harmful to human health and destroy the ecological environment.

In order to avoid the volatilization of a large amount of organic solvents, researchers have developed water-based polyurethane coatings; generally water-based polyurethane greatly reduces the content of VOC, but due to the unstable performance, isocyanate will react with water to generate carbon dioxide gas, which can easily cause Gelling, peeling from the base material, vesicles and other disadvantages

However, the price of water-based two-component polyurethane adhesives is relatively high, so the current application of water-based two-component polyurethane adhesives has certain limitations.

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