| abstract |
PCT No. PCT/EP95/00541 Sec. 371 Date Aug. 28, 1996 Sec. 102(e) Date Aug. 28, 1996 PCT Filed Feb. 15, 1995 PCT Pub. No. WO95/23176 PCT Pub. Date Aug. 31, 1995A process is disclosed for increasing the molecular weight of polyesters, polyester copolymers or polyester blends, which comprises heating a polyester blended with a tetracarboxylic acid dianhydride and a sterically hindered hydroxyphenylalkylphosphonic acid ester or half-ester to above the melting point (glass transition temperature) of the polyester. |