| 摘要 |
Methods and apparati have been developed for producing a suspension of predominantely amorphous polymer particles, wherein the method includes thermally treating a suspension that includes crystalline or semi-crystallin e polymer particles. The thermal treatment includes (a) heating a suspension o f polymer particles of an appropriate size to a temperature effective to cause the polymer to become amorphous, and then (b) cooling the suspension of amorphous polymer particles below the melting point of the polymer at a rate effective to prevent substantial coalescence of the polymer particles. The method and apparati are effective for use with a variety of polymers having suitable crystallization parameters, although polyhydroxyalkanoate (PHA) polymers are preferred, particularly in an aqueous suspension medium. For PH A polymers, the polymer particles subjected to treatment preferably are of a size of less than 5.mu.m, or more preferably less than 1.5.mu.m in diameter.
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