A kind of preparation method of hydrolysis-resistant PBT polyester resin

Abstract

The invention relates to a preparation method of a hydrolysis-resistant PBT polyester resin. Firstly, terephthalic acid, 1,4-butanediol, an organic titanate compound and magnesium phosphate are mixed to form a slurry, which is subjected to an esterification reaction to obtain Prepolymer, and then carry out melt polycondensation reaction to obtain PBT polyester resin base sheet, and finally mix PBT polyester resin base sheet with end-capping modifier and organic phosphate compound in a twin-screw extruder to obtain hydrolysis-resistant PBT Polyester resin; in terms of mass fraction, the addition ratio of each substance required in the mixing preparation process is: 97-99 parts of PBT polyester resin substrate, 0.5-1 part of end-capping modifier, 0.01-1 part of organic phosphate compound 1 part; the end-cap modifier is a hyperbranched polyester with terminal hydroxyl numbers of 6-100 and branch units comprising 2,2-dimethylolpropionic acid. The preparation method of the invention is simple, and the prepared hydrolysis-resistant PBT polyester resin has excellent comprehensive properties.

Description

technical field [0001] The invention belongs to the technical field of polyester resin and relates to a preparation method of hydrolysis-resistant PBT polyester resin. Background technique [0002] Polybutylene terephthalate (PBT) is a thermoplastic polyester formed by polycondensation of terephthalic acid (PTA) and butanediol (BDO). It has excellent mechanical, physical and chemical properties, such as easy processing, High temperature resistance, chemical resistance, oil resistance, good mechanical strength and other properties, have been widely used in the fields of automobiles, machinery, instruments, electronics, household appliances, textiles and civilian use. [0003] PBT resin has excellent hydrolysis resistance under dry and hot conditions, but in many applications, such as underground optical cables, automotive parts, electrical appliances, solar films, etc., PBT resin is very prone to hydrolysis in the case of a large amount of moisture and high temperature aging....

AI Technical Summary

Problems solved by technology

[0008] The invention provides a method for preparing a hydrolysis-resistant PBT polyester resin, the purpose of which is to solve the problem of poor hydrolysis resistance of PBT resins in the prior art, resulting in a decrease in product molecular weight, serious loss of mechanical properties, and limited applications, as well as the improvement of PBT in the prior art. The preparation process of the hydrolysis resistance of polyester resin is complicated, and it is necessary to add chain extender, nucleating agent and other additives at the same time as the end-capping agent, which will affect its processing performance and color value.