This invention relates to a novel thermoplastic and amorphous polyimide which is readily soluble in organic solvent, a novel aromatic diamino compound used for the polyimide, a preparation process thereof, a polyimide-based resin composition comprising the thermoplastic polyimide and a fibrous reinforcement, a process for preparing the resin composition, an injection molded article of the resin composition, a polyimide-based composite obtained by molding the above soluble and thermoplastic polyimide in combination with a fibrous reinforcement, and a fibrous reinforcement having a surface modified with the above polyimide. The polyimide comprise a requisite structural unit having one or more recurring structural units of the formula: ##STR1## wherein m and n are individually an integer of 0 or 1, and R is ##STR2## The polyimide of the invention is essentially amorphous, excellent in melt flow stability in the decreased temperature as compared with conventionally known polyimide and has greatly improved processability. The polyimide of the invention obtained by using a novel aromatic diamino compound as a monomer can control various properties such as melt flow ability and solubility in solvents by side chains and not by principal chain of polyimide. Thus, excellent melt flow property and solubility in solvents can be obtained while maintaining high heat resistance and adhesive property which are derived from benzophenone structure of the diamino compound of the the invention.
本发明涉及一种新型热塑性非晶态聚
酰亚胺,该聚
酰亚胺易溶于有机溶剂,一种用于制备聚
酰亚胺的新型芳香族二
氨基化合物,其制备方法,包括热塑性聚
酰亚胺和纤维增强剂的聚
酰亚胺基
树脂组合物,该组合物的制备方法,组合物的注塑成型产品,通过在可溶的热塑性聚
酰亚胺中与纤维增强剂结合而得到的聚
酰亚胺基复合材料,以及具有上述聚
酰亚胺表面改性的纤维增强剂。该聚
酰亚胺包括一个必需的结构单元,该单元具有一个或多个重复的结构单元,其
化学式为:其中m和n分别是0或1的整数,R为:该发明的聚
酰亚胺基本上是非晶态的,在低温下具有比传统聚
酰亚胺更好的熔融流动稳定性,并且具有大大改善的加工性能。通过使用新型芳香族二
氨基化合物作为单体制备的聚
酰亚胺可以通过侧链而不是主链控制各种性质,例如熔融流动性和溶解性。因此,在保持源自该化合物的
二苯甲酮结构的高耐热性和粘接性的同时,可以获得优异的熔融流动性和溶解性。