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和非晶态聚
酰亚胺,该聚
酰亚胺在有机溶剂中易溶,一种用于聚
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,制备该
树脂组合物的方法,
树脂组合物的注射成型制品,通过模压上述可溶性和热塑性聚
酰亚胺与纤维增强剂的组合得到的聚
酰亚胺基复合材料,以及用上述聚
酰亚胺改性的纤维增强剂。该聚
酰亚胺包括必需的结构单元,其中包含一个或多个重复的结构单元,其
化学式为:##STR1## 其中m和n分别是0或1的整数,R是##STR2## 本发明的聚
酰亚胺基本上是非晶态的,在低温下具有比传统已知聚
酰亚胺更好的熔流稳定性,并且具有极大的改善加工性能。本发明的聚
酰亚胺是通过使用新型芳香族二
氨基化合物作为单体获得的,可以通过侧链而不是主链控制熔流能力和溶解性等各种性质。因此,可以在保持由本发明的二
氨基化合物的苯并酮结构导致的高耐热性和粘合性的同时,获得优异的熔流性和溶解性。