Preparation method of aromatic polyester LCP composite diaphragm and composite diaphragm prepared by preparation method

Abstract

The invention discloses a preparation method of an aromatic polyester LCP composite diaphragm and the composite diaphragm prepared by the preparation method. The preparation method comprises the following steps: (1) dissolving aromatic polyester LCP in a mixed solvent of N, N-dimethylformamide, acetone and diphenyl ether according to a volume ratio of (70-80): (15-20): (5-10), so as to prepare animpregnation solution with a concentration of 35-47 g / L; (2) soaking a diaphragm base material in the solution obtained in the step (1) for 0.5-2.5 hours, and then taking out the diaphragm base material; and (3) carrying out vacuum drying on the product obtained in the step (2) at 75-90 DEG C for 5-6 hours. According to the preparation method, the structural strength of the diaphragm is obviouslyimproved, and the thermal shrinkage rate is remarkably reduced. The invention further discloses the aromatic polyester LCP composite diaphragm prepared by the preparation method, the porosity of the diaphragm is greatly reserved, the ionic conductivity of the diaphragm is not influenced, and the increase of the thickness can be avoided.

Description

technical field [0001] The invention relates to the field of chemical industry, more specifically, to a method for preparing an aromatic polyester LCP composite diaphragm and the composite diaphragm prepared therefrom. Background technique [0002] Aromatic polyester refers to the polymer obtained by condensation reaction of aromatic dicarboxylic acid and diol, among which the aromatic polyester produced by the reaction of aliphatic diol is called non-whole aromatic polyester, such as polyparaphenylene Ethylene glycol diformate, polytrimethylene terephthalate, polybutylene terephthalate, etc., aromatic polyesters produced by the reaction of aromatic diols / phenols are called fully aromatic polyesters, such as Aromatic polyesters made from bisphenol A, bisphenol F, hydroquinone, resorcinol, biphenol, etc. The common point of these polyesters is that the main chain contains a large number of benzene ring structures. And most of them have liquid crystal properties, so they are ...

AI Technical Summary

Problems solved by technology

However, this treatment method can only involve the surface of the battery separator. Although it improves the structural strength and thermal shrinkage, it will reduce the porosity of the separator and increase the thickness of the separator, which will affect the conductivity of the electrolyte.

In this regard, some technicians try to use the method of solution impregnation to compound the aromatic polyester LCP inside the battery separator, but the solubility of the aromatic polyester LCP is not good, and the viscosity of the solution is high, which will block the pores of the separator even more. Dipping method is difficult to achieve

Images