| 摘要 |
<p>Polyester films are modified by the addition of a high molecular weight polyethylene glycol and an alkali metal salt of a sulfonic acid-substituted dicarboxylic acid ester to the reaction medium during the polymerization process. Films prepared for example, from diesters of terephthalic acid in the presence of the modifiers of this invention produce films which exhibit good permeability to water vapor.</p> |
