A novel heat-fusible copolymer which has excellent mechanical strength, radiation resistance, chemical resistance, low-temperature characteristics, heat resistance, processability, and adhesion and can simultaneously meet requirements for low water absorption and excellent dielectric properties; and film, powder, laminated film, heat-fusible film for covering wires, laminated heat insulator, electronic module, and capacitor, each produced from a thermoplastic polyimide resin composed mainly of the above copolymer and suitable for use as electronic components, materials for electronic circuit components capable of coping with a need for high-density packaging and the like. The copolymer has a combination of a glass transition point of 100 to 250 °C, a water absorption of not more than 1 %, and a permittivity of not more than 3 and is represented by general formula (I), wherein Ar1 represents a tetravalant organic group; Ar2 represents a divalent organic group; R represents a divalent organic group; X is a trivalent bonding group; m and n are each an integer of 0 or more, provided that the sum of m and n is 1 or more; and 1 is an integer of 1 or more.
一种新型热熔共聚物,它具有优异的机械强度、耐辐射性、耐
化学性、低温特性、耐热性、可加工性和粘附性,并能同时满足低吸
水性和优异介电性能的要求;以及由主要由上述共聚物组成的热塑性聚
酰亚胺树脂制成的薄膜、粉末、层压薄膜、用于包覆导线的热熔薄膜、层压隔热材料、电子模块和电容器,每种材料都适用于电子元件、能满足高密度封装需求的电子电路元件材料等。该共聚物的
玻璃化转变点为 100 至 250℃,吸
水率不超过 1%,导热系数不超过 3,由通式(I)表示,其中 Ar1 代表四价有机基团;Ar2 代表二价有机基团;R 代表二价有机基团;X 为三价键合基团;m 和 n 均为 0 或 0 以上的整数,但 m 和 n 之和为 1 或 1 以上;1 为 1 或 1 以上的整数。