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