Water soluble acrylic acid epoxy resin and preparation method thereof

Abstract

The invention relates to water soluble acrylic acid epoxy resin and a preparation method thereof. The epoxy resin is emulsion formed by neutralizing and self-emulsifying a product of a catalytic esterification reaction of acrylic acid resin and epoxy resin, and the variation of tu-4 cup viscosity of the emulsion stored for 6 months is less than 5 percent; epoxy equivalent of the epoxy resin is between 180 and 5,000g/mol, and the epoxy resin accounts for 10 to 80 percent of gross weight of the epoxy resin and the acrylic acid resin; the acrylic acid resin is polymerized from hydroxyl-containing acrylic acid, carboxyl-containing acrylic acid, other acrylic acids and styrene monomers which are initiated by peroxide, and has the acid value of between 50 and 500mgKOH/g and the number average molecular weight of between 5,000 and 60,000g/mol; and the epoxy resin with the epoxy equivalent less than 1,300g/mol does not need bisphenol A chain extension, has simple operation, and is convenient for regulating the proportion of the epoxy resin. The method can be used for preparing the water soluble acrylic acid epoxy resin with wider proportion of the epoxy resin and stable storage.

Description

technical field [0001] The invention relates to a water-based acrylic epoxy resin and a preparation method thereof. Background technique [0002] Water-based coatings use water instead of organic solvents, which can greatly reduce the use of organic solvents in the coatings industry. Its effectiveness, cost and environmental acceptability are obvious, so it is increasingly favored by people. [0003] The water-based resin, which is the main film-former of water-based paint, and its preparation method are the technical focus of water-based paint. At present, the preparation methods of water-based acrylic epoxy resins used as film formers generally fall into two categories: physical blending and chemical modification. However, physically blended waterborne acrylic epoxy resins generally have storage stability problems, while chemically modified waterborne acrylic epoxy resins have different properties depending on the chemical modification method, for example: waterborne epox...

AI Technical Summary

Problems solved by technology

However, physically blended waterborne acrylic epoxy resins generally have storage stability problems, while chemically modified waterborne acrylic epoxy resins have different properties depending on the chemical modification method, for example: waterborne epoxy resins prepared by free radical grafting Acrylic epoxy resin, because of the low grafting rate, the actual final product is still a mixture, including ungrafted epoxy resin, acrylic resin and epoxy resin graft, free polyacrylic resin, etc., so There are still problems with the storage stability of the resin; another method is to use the epoxy group of the epoxy resin and the carboxyl group of the acrylic resin to combine the acrylic resin and the epoxy resin to form a new macromolecule through an esterification reaction. Oxygen resin has two functional groups, and acrylic resin has multiple functional groups. When the two undergo esterification reaction, gelation is easy to occur. Although it is found that a large amount of tertiary amine is used as a catalyst, gelation can be effectively avoided. However, as a starting The epoxy resin of the raw material is a small molecule epoxy resin with an epoxy equivalent of 180-200g / mol. After bisphenol A is extended to an epoxy equivalent of 750-5000g / mol, it is esterified with an acrylic resin. It is cumbersome, and it is difficult to regulate the proportion of epoxy resin in the whole waterborne acrylic epoxy resin according to the needs. Therefore, there are few varieties of waterborne acrylic epoxy resin, which limits its application range.

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