Novel wholly aromatic copolyester, process for production thereof, and film melt-shaped therefrom
申请人:TEIJIN LIMITED
公开号:EP0045499A2
公开(公告)日:1982-02-10
A wholly aromatic copolyester composed mainly of isophthalic acid units and hydroquinone units, the total proportion of said isophthalic acid units and hydroquinone units being at least about 80 mole% based on the entire units, said wholly aromatic copolyester having a terminal carboxyl group concentration, measured by the method described in the specification, of not more than about 90 eq/106 g and a reduced viscosity, determined at 35°C in a mixed solvent of phenol and tetrachloroethane in a weight ratio of 4:6 in a concentration of 1.2 gfdl of at least about 0.6 and being substantially linear and melt-shapable and substantially free from a halogen atom bonded to the molecular chain, and a film prepared therefrom by melt shaping.
The wholly aromatic copolyester can be prepared by a process which comprises polycondensing under heat in the presence of a polycondensation catalyst (a) a reaction mixture consisting of a major proportion of a diaryl ester of isophthalic acid and hydroquinone and a minor proportion of at least one other component selected from diaryl esters of aromatic dicarboxylic acids other than isophthalic acid, aromatic dihydroxy compounds other than hydroquinone and aryl hydroxyenboates or (b) a reaction mixture consisting of a major proportion of isophthalic acid, hydroquinone and a diaryl carbonate and a minor proportion of at least one other component selected from aromatic dicarboxylic acids other than isophthalic acid, aromatic dihydroxy compounds other than hydroquinone, hydroxybenzoic acid and aryl hydroxybenzoates, and after the reduced viscosity of the polymer formed in the reaction system has reached about 0.2, performing the polycondensation at a temperature lower than the crystalline melting point of the polymer while maintaining the reaction system in a molten condition; or which comprises polymerizing the wholly aromatic copolyester having a reduced viscosity of at least 0.6 prepared by the above process or a wholly aromatic copolyester having a reduced viscosity of less than about 0.6 in the solid phase in a manner known per se under reduced pressure or while passing an inert gas into the reaction system.
The film can be used as films for metal vapor depocition, films for printed circuits and electrical insulating films by using their excellent heat resistance.
一种主要由间苯二甲酸单元和对苯二酚单元组成的全芳香族共聚聚酯,所述间苯二甲酸单元和对苯二酚单元的总比例以整个单元为基准至少约为 80 摩尔%,所述全芳香族共聚聚酯的末端羧基浓度(用说明书所述方法测定)不超过约 90 eq/106 g,在 35°C 时,在重量比为 4:6 的苯酚和四氯乙烷混合溶剂中测定的降低粘度为 1.2 gfdl至少约为0.6,基本上呈线性,可熔融成型,基本上不含与分子链键合的卤原子,以及由其通过熔融成型制备的薄膜。
全芳香族共聚聚酯可通过以下工艺制备: 在缩聚催化剂存在下,在加热条件下进行缩聚 (a) 反应混合物,其主要成分为间苯二甲酸二芳基酯和对苯二酚,次要成分为至少一种选自间苯二甲酸以外的芳香族二羧酸二芳基酯的其他成分、或 (b) 反应混合物,其主要成分为间苯二甲酸、对苯二酚和碳酸二芳基酯,次要成分为至少一种选自间苯二甲酸以外的芳香族二羧酸、对苯二酚以外的芳香族二羟基化合物、羟基苯甲酸和羟基苯甲酸芳基酯的其他成分。2,在低于聚合物结晶熔点的温度下进行缩聚,同时将反应体系保持在熔融状态;或者包括在减压或向反应体系通入惰性气体的情况下,以本身已知的方式在固相中聚合通过上述工艺制备的粘度降低至少为 0.6 的全芳香族共聚聚酯或粘度降低小于约 0.6 的全芳香族共聚聚酯。
这种薄膜具有优异的耐热性,可用作金属蒸镀薄膜、印刷电路薄膜和电绝缘薄膜。