PURPOSE: A reaction mixture consisting of isophthalic diaryl ester, hydroquinone and other components is heated under specific conditions to effect polycondensation reaction, thus giving the titled linear polyester that is melt-moldable and gives molded products with high heat resistance.
CONSTITUTION: The polycondensation reaction between (A) aromatic dicarboxylic diaryl esters mainly consisting of diaryl isophthalate, (B) hydroquinone and (C) an aromatic dihydroxy compound, preferably resorcinol, is conducted in the presence of a catalyst by keeping the mixture in a melted state at temperatures lower than the crystal melting point of the polymer after its reduced viscosity reaches 0.15 to give the objective polyester that contains isophthalic acid and hydroquinone as the major components and component C of formulaIWIII as a copolymer component, has terminal carboxyl groups of less than 90 equivalent/ 106 grams of the polymer and higher than 0.6 reduced viscosity with no halogen linking to its molecular chains.
HIRABAYASHI YASUJI
YOSHIDA KAZUSHI
INADA HIROO
