The present invention relates to a polyester or copolyester composition containing a substituted cyclic anhydride, having a carboxyl end group of greater or equal to 25 mmol/kg. The present invention also concerns a method of making such a polyester or copolyester by late injection of the substituted cyclic anhydride at the end of polycondensation, or alternatively adding the substituted cyclic anhydride to the preform injection molding machine, prior to stretch blow molding a container.
本发明涉及一种含有取代环酐的聚酯或共聚物组合物,其羧基端基大于或等于 25 mmol/kg。本发明还涉及一种制造这种聚酯或共聚多酯的方法,即在缩聚结束时后期注入取代的
环酸酐,或者在拉伸吹塑成型容器之前将取代的
环酸酐加入瓶坯注塑机中。