Dry mixing extinction type powder coating material with good low-temperature curing property, and preparation method thereof

Abstract

The present invention relates to a two-component polyester resin for a low-temperature curing dry-mixing extinction powder coating material, and a power composition thereof. According to the present invention, mainly the high acid value component of the dry-mixing extinction polyester resin increases the types and the amounts of triols having high grafting degree; the final acid value of the polyester resin is increased to 65-75 mg KOH / g so as to improve the activity; the low acid value component of the dry-mixing extinction polyester resin mainly selects a lot of flexible raw materials to adjust the melting viscosity of the polyester while high-activity polybasic acid such as maleopimaric acid and benzenetetracarboxylic acid are introduced to perform the end capping so as to increase the acid value to 28-35 mg KOH / g, such that the low-temperature curing performance is ensured; and the dry mixing powder coating material prepared from the high-low acid value component polyester resin can be cured at the low temperature of 140-160 DEG C, and can achieve the extinction effect of the gloss of 20-40%.

Description

technical field [0001] The invention belongs to the field of powder coating preparation; in particular, it is a dry mixed matting type two-component polyester resin powder coating composition with good low-temperature curing performance and a preparation method thereof. Background technique [0002] Since its appearance in the 1970s, powder coatings do not contain organic solvents and are 100% solid components. Compared with conventional coatings, powder coatings have the advantages of no pollution, saving energy and resources, high mechanical strength of coating films, and full recovery of excess coatings. Advantages, it is more and more widely used in the coating of household appliances, automobile industry, office appliances, metal materials, outdoor buildings and other shells. [0003] As customers have higher and higher requirements for powder coatings, matte powder coatings are widely used in the industry as a variety with better decoration. At present, in the field o...

AI Technical Summary

Problems solved by technology

Specifically, it is to add hydroxyl-terminated perfluoropolyether to the high acid value polyester resin during the preparation process to further improve the physical properties of the coating, and at the same time to overcome the poor dispersion of hydroxyl-terminated perfluoropolyether in the reaction system To solve the problem, add phosphate derivatives to make cross-combination between hydroxyl-terminated perfluoropolyether and polyols during the esterification process to improve product stability; for low-acid value polyester resins, add silane coupling agents during the preparation process , uniformly dispersed into the low acid value polyester resin, during the curing heating process, cross-combined with the molecular chains of the high acid value polyester resin to reduce its curing temperature and improve the adhesion of the entire coating