Method for preparing maleimide stop end type polyimide resin

Abstract

The invention relates to a method for preparing maleimide stop end type polyimide resin, comprising the following steps: diamine, maleic anhydride and tetracarboxylic dianhydride are sequentially added to a polar solvent according to a molar ratio of (n+1):2:n to have the solid content of 25 plus or minus 1 percent (gram/milliliter) and then stirred for 8-24 hours at room temperature under the protection of nitrogen to generate intermediate polyamide acid, then a dehydrating agent acetic anhydride, a dehydrating catalytic agent triethylamine and the polar solvent are added into the intermediate polyamide acid so that the solid content is reduced to 15 percent (gram/milliliter) and then chemical imidization for 4-6 hours is conducted under the temperature of 30 DEG C-80 DEG C, then reaction liquid is poured into anhydrous ethanol which is stirred at high speed to obtain deposits, and the deposits are sequentially and sufficiently washed by the anhydrous ethanol and anhydrous ether and then dried in vacuum so as to obtain the maleimide stop end type maleimide polyimide resin, or heat dehydration cyclizing is conducted on the generated intermediate polyamide acid under the action of entrainer ortho-dichlorobenzene and chlorobenzene or methylbenzene to obtain outcomes of the maleimide stop end type maleimide polyimide resin.

Description

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AI Technical Summary

Benefits of technology

This new type of polymer material made by modifying certain chemicals called Maleimides (Malehydrides) was developed earlier but it still had some drawbacks like poor water resistance or instability during use due to its hydrophobicity when mixed into other materials. To solve this problem, researchers have been working on improving these properties through various methods including introducing specific groups onto Matsumoto' s catalyst residues or adding different types of substituents around them. These modifications resulted in improved physical characteristics without affecting their original function.

Problems solved by technology

This patented technical problem addressed in this patents relates to improving flexibility and durability when producing an adhesion-less double-ply flexible coated liquid crystal display panel (LCD). Current solutions involve adding polymerizable monomers like diacid chloroacrylate(BCMA)-based copolymerized acids onto the surfaces of both layers during fabrication processes. These modifications result in decreased strengths over time due to reduced solubility of BCMA and improved stability against UV ray exposures. Additionally, current biaxially oriented plastic films require expensive special facilities and strict environment control regulations. Therefore there exists a demand for new types of compositions containing less volatile components while maintaining their good physical characteristics and compatibility with existing systems without compromising their quality.

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