Abstract: The present invention provides a method of producing a polyethylene terephthalate graft copolymerized resin, comprising subjecting the following mixture to a homogeneous reaction at a temperature of 250° C. or higher to impart a high melt viscosity to the mixture, the mixture containing (A) 100 parts by weight of a polyethylene terephthalate polyester as a main material, (B) 0.01 to 2 parts by weight of a polymeric polyfunctional epoxy compound containing 7 to 100 epoxy groups in a molecule and having a molecular weight of 1,000 to 300,000 as a coupling agent, (C) 0.01 to 1 part by weight of a metal salt of an organic acid as a coupling reaction catalyst, and (D) 0 to 100 parts by weight of an aromatic alicyclic polyester and/or an aromatic aliphatic polyester each having a carboxyl group in an aromatic nucleus as an auxiliary material.

Abstract: The present invention provides a method of producing a polyethylene terephthalate graft copolymerized resin, comprising subjecting the following mixture to a homogeneous reaction at a temperature of 250° C. or higher to impart a high melt viscosity to the mixture, the mixture containing (A) 100 parts by weight of a polyethylene terephthalate polyester as a main material, (B) 0.01 to 2 parts by weight of a polymeric polyfunctional epoxy compound containing 7 to 100 epoxy groups in a molecule and having a molecular weight of 1,000 to 300,000 as a coupling agent, (C) 0.01 to 1 part by weight of a metal salt of an organic acid as a coupling reaction catalyst, and (D) 0 to 100 parts by weight of an aromatic alicyclic polyester and/or an aromatic aliphatic polyester each having a carboxyl group in an aromatic nucleus as an auxiliary material.

Abstract: The invention provides a method for producing a foamed article comprising the steps of: heating a mixture comprising (a) 100 parts by weight of linear saturated polyester, (b) 0.1 to 10 parts by weight of a mixture as a coupling agent of 0 to 100% by weight of a compound having two epoxy groups in the molecule, and 100 to 0% by weight of a compound having two or more epoxy groups, and (c) 0.01 to 5 parts by weight of a metal salt of a carboxylic acid as a coupling reaction catalyst, at a temperature of a melting point of the polyester or more to provide a melt flow rate of 50 g/10 minutes or less and swell of 10 to 200%, whereby a polyester resin is formed; and heating and foaming the polyester resin using a foaming agent .

Abstract: The present invention provides a masterbatch method for producing a polyester resin and articles thereof; comprising reacting following materials uniformly at a temperature equal to or greater than the melting point of a polyester, the materials comprising: (1) 100 parts by weight of saturated straight-chain polyester A; (2) 1 to 10 parts by weight of binder masterbatch D comprising: a mixture containing a compound having two epoxy groups and a compound having an average number of epoxy groups of 2.1 or more; (3) 0.25 to 10 parts by weight of catalyst masterbatch G comprising: a metal carboxylate, whereby the melt viscosity of the polyester increases so that the melt flow rate (MFR) becomes 50 g/10 min or less, and the degree of swelling of the polyester increases to between 5% and 200%, thus resulting in a high-quality resin having excellent mechanical properties. The resin can be advantageously used for films, sheets, foamed materials, pipes, cushioning, heat insulators, packing materials, and so forth.

Abstract: The present invention provides a masterbatch method for producing a polyester resin and articles thereof; comprising reacting following materials uniformly at a temperature equal to or greater than the melting point of a polyester, the materials comprising: (1) 100 parts by weight of saturated straight-chain polyester A; (2) 1 to 10 parts by weight of binder masterbatch D comprising: a mixture containing a compound having two epoxy groups and a compound having an average number of epoxy groups of 2.1 or more; (3) 0.25 to 10 parts by weight of catalyst masterbatch G comprising: a metal carboxylate, whereby the melt viscosity of the polyester increases so that the melt flow rate (MFR) becomes 50 g/10 min or less, and the degree of swelling of the polyester increases to between 5% and 200%, thus resulting in a high-quality resin having excellent mechanical properties. The resin can be advantageously used for films, sheets, foamed materials, pipes, cushioning, heat insulators, packing materials, and so forth.