METHOD OF PRODUCING POLYESTER HAVING HIGH DEGREE OF POLYMERIZATION

摘要

PROBLEM TO BE SOLVED: To provide a method of producing a polyester having a high degree of polymerization which is more economical than the conventional method, in the ring opening polymerization using a cyclic polyester oligomer. SOLUTION: In the method of producing a polyester having a high degree of polymerization, the cyclic polyester oligomer is compounded with a polyester at a weight ratio of 1.5 to 9.5 and they are mixed and heated in the ring opening polymerization of the cyclic polyester oligomer.