Preparation method of soluble and fusible polyimide precipitation fiber

Abstract

The invention discloses a preparation method of a soluble and fusible polyimide precipitation fiber. The preparation method comprises the following steps: firstly, mixing calcium chloride, N,N-dimethylacetamide and water in proportion, and uniformly stirring, so that a precipitation agent is obtained; secondly, carrying out reaction on a diamine monomer and a dianhydride monomer in an aprotic polar solvent to generate polyamide acid solution, then carrying out chemical cyclodehydration to obtain polyimide solution, and finally diluting to obtain polyimide stock solution; and thirdly, respectively injecting the precipitation agent and the polyimide stock solution into a precipitation machine, carrying out high-speed stirring by virtue of the precipitation machine, shearing to obtain suspension liquid, and then filtering and washing, so that the soluble and fusible polyimide precipitation fiber is obtained. The prepared polyimide precipitation fiber not only can well meet wet papermakingrequirement but also can be fused, so that the polyimide precipitation fiber can be tightly combined with a polyimide chopped fiber during hot press molding, and finally the polyimide precipitation fiber can be applied to preparation of high-performance high-temperature-resistant paper products such as high-strength lithium ion diaphragm paper, capacitor paper, insulation paper and honeycomb paper.

Description

technical field [0001] The invention belongs to the technical field of polyimide, and in particular relates to a preparation method of soluble and meltable polyimide precipitated fibers. Background technique [0002] Polyimide is a polymer material with high heat resistance in industrial applications. It has excellent heat resistance, low temperature resistance, insulation, flame retardancy, corrosion resistance, radiation resistance, stable size, stable chemical properties, high strength, High modulus, strong creep resistance, excellent friction performance, non-toxic and other excellent properties, widely used in aviation, aerospace, electrical appliances, machinery, chemicals, microelectronics and other high-tech fields. At present, the technology and production capacity of the United States and Japan are still in the leading position in the world. [0003] Due to the characteristics of imide groups, polyimide has better heat resistance and chemical stability than aramid...

AI Technical Summary

Problems solved by technology

Due to the thermal imidization of polyamic acid fibrids, moisture will be generated, which will lead to agglomeration of fibrids, which will greatly affect the performance of polyimide paper made by wet papermaking

[0005] In addition, the existing polyimide fibrids are basically not melted, so they cannot be tightly combined with polyimide chopped fibers during hot pressing, thus affecting the strength of the prepared polyimide paper and making it difficult to prepare Lithium battery separator paper, capacitor paper, insulating paper, honeycomb paper and other high-performance high-temperature resistant polyimide paper