摘要 |
A polymer melt may be devolatilized to less than 500, preferably less than 150 ppm of residual volatile material by injecting into the melt an amount of fluid which will condense but not freeze at pressures of less than about 20 mm Hg, in an amount greater than the amount of residual volatile material in the polymer melt, typically not more than about 10 weight % and passing the melt through a zone of pressure of 8 mm of Hg or less at a temperature of from 200 DEG to 350 DEG C.
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