| 摘要 |
A process for the improvement of the drawing ability of polyester, pellets of which are thermally post-treated in the solid phase in an inert atmosphere, containing a precise concentration of water vapor. The water vapor concentration is equal to the amount of water, plus 15%/minus 50%, which could theoretically be formed, at the polyester end viscosity, from the -COOH end groups and the excess -OH end groups of the polyester. An equimolar quantity of the vapor of the alkanediol, which serves as the diol reactant for the polyester, may be substituted for all or part of the water vapor.
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