Patent ID: 9156943
Filing Date: 2015-10-13
Classification: C08G

Abstract:
1. A process for manufacturing a modified polyester, comprising the steps of: carrying out an esterification reaction of diacid, diol and a branching agent having at least three carboxyl groups at a temperature of about 180 to 300° C. and a pressure of about 1 to 4 bar to obtain a product of esterification, wherein the molar ratio of the diacid to the diol is about 1:1 to 1:2, and the branching agent is present in an amount of 0.02 to 1 mol % based upon the total moles of the diacid and the diol; and carrying out a polycondensation reaction of the product of esterification and diamine at a pressure below about 0.01 bars to obtain the modified polyester, wherein the diamine is present in an amount of about 0.07 to about 0.22 mol % based upon the total moles of the diacid and the diol; wherein the diacid comprises a combination of at least one aliphatic diacid and at least one aromatic diacid, and the aromatic diacid is present in an amount no greater than about 10 mol % based upon the total moles of the diacid and the diol and the modified polyester is a thermally induced shape-memory material having an activation temperature of about 40 to 99° C., a percent elongation of about 29.9% to 40.9% at break, a bending modulus of about 40.3 MPa to about 20.1 Mpa.