摘要 |
A method for preventing the precipitation of ethylene-vinyl alcohol copolymers in a distillation vessel. The vessel contains water, methanol, and ethylene-vinyl alcohol copolymers. The method includes the step of adding to the distillation vessel from 1 to about 1,000 ppm of at least one surfactant selected from the group consisting of alkyl, aryl, alkylaryl and arylalkyl sulfonic acids having a carbon length of from 4 to about 30 carbons. Preferably, the surfactant is dodecylbenzenesulfonic acid.
|