Abstract: A solid-phase polymerization method of high-molecular-weight aliphatic polyester conducts the solid-phase polymerization of aliphatic polyester prepolymer under a gas stream containing sulfonic acid catalyst. The method features preparing metal free aliphatic polyester with high molecular weight, good color and luster and perfect thermal stability efficiently. The non-metal-ion aliphatic polyester is not only applicable to common use, but is also suitable as high value-added medical material and packing material which contacts with food directly than other metal-containing polyester.

Abstract: A solid-phase polymerization method of high-molecular-weight aliphatic polyester conducts the solid-phase polymerization of aliphatic polyester prepolymer under a gas stream containing sulfonic acid catalyst. The method features preparing metal free aliphatic polyester with high molecular weight, good color and luster and perfect thermal stability efficiently. The non-metal-ion aliphatic polyester is not only applicable to common use, but is also suitable as high value-added medical material and packing material which contacts with food directly than other metal-containing polyester.

Abstract: A method for producing an aliphatic polyester resin including a melt polymerization step and a subsequent solid phase polymerization step, using a sulfonic acid group-containing compound as a catalyst, wherein the addition amount of the sulfonic acid group-containing compound during melt polymerization is 300 to 3000 ppm with respect to a raw material monomer calculated as sulfur atoms, the content of the sulfonic acid group-containing compound during melt polymerization is 300 to 3000 ppm with respect to a produced polymer calculated as sulfer atoms, and a residual rate of the sulfonic acid group-containing compound after solid phase at polymerization is more than 50.

Abstract: A method for producing an aliphatic polyester resin including a melt polymerization step and a subsequent solid phase polymerization step, using a sulfonic acid group-containing compound as a catalyst, wherein the addition amount of the sulfonic acid group-containing compound during melt polymerization is 300 to 3000 ppm with respect to a raw material monomer calculated as sulfer atoms, the content of the sulfonic acid group-containing compound during melt polymerization is 300 to 3000 ppm with respect to a produced polymer calculated as sulfer atoms, and a residual rate of the sulfonic acid group-containing compound after solid phase at polymerization is more than 50%.