A kind of preparation method of cross-linked aqueous acrylic acid emulsion

Abstract

The invention discloses a preparation method of a cross-linked water-based acrylic emulsion. It comprises the following steps: A, preparation of modified dialdehyde cross-linking agent; the general formula of said dialdehyde cross-linking agent is CHO-R-CHO, wherein R is a linear or branched alkyl group, or linear or branched The aryl group of chain; B, prepare the acrylate copolymer emulsion containing amino functional group; C, add the modified dialdehyde cross-linking agent that A step gains in the acrylate copolymer emulsion that B step gains, obtain cross-linked aqueous acrylic acid emulsion , the cross-linking reaction formula is: 2P‑NH 2 +CHO‑R‑CHO→P‑N=CH‑R‑CH=N‑P+H 2 O. The cross-linked coating film obtained by the invention has good abrasion resistance, chemical resistance, water resistance and tensile strength, and successfully solves the problem of yellowing.

Description

technical field

[0001] The invention relates to a preparation method of cross-linked water-based acrylic emulsion. Background technique

[0002] Due to its low VOC, water-based coatings are an important direction for the development of environmentally friendly coatings. Acrylic resin water-based coatings have attracted much attention due to their excellent weather resistance, acid and alkali resistance, and water resistance. However, there is a contradiction between low-temperature film-forming and high hardness in water-based acrylic resin coatings, which limits its wide application. In order to solve this problem, the most effective way is to introduce a cross-linking agent to make the molecules form a cross-linked structure. If the emulsion polymer film can form a cross-linked structure, it can not only improve the physical and chemical stability of the coating film, but also improve its tensile strength and wear resistance. Contents of the invention

[0003] The obj...

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