PROCESS FOR PREPARING POLYETHYLENE TEREPHTHALATE Russian patent published in 1995 - IPC

FIELD: synthesis of polyethylene terephthalate having a reduced content of carboxyl groups and improved thermal resistance. SUBSTANCE: synthesis is effected by transesterification of dimethyl terephthalate and ethylene glycol in the presence of manganese acetate at 220 C followed by polycondensation qt 285 C at lower pressure in the presence of antimony trioxide and 0.005 to 0.2 of a thermal stabilizer such as oxyethylene diphosphonic acid or a solution thereof in an industrial mixture of methyl phosphates. EFFECT: more efficient preparation process. 1 tbl