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Redistribution modulo null of organicity polyester carbonate
Redistribution modulo null of organicity polyester carbonate
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机译：有机聚酯碳酸酯的模量再分布
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摘要
PROBLEM TO BE SOLVED: To modify a polyester carbonate having a certain initial weight- average molecular weight into a polyester carbonate having a different redistrib uted molecular weight by heating a mixture of the starting polyester carbonate with a specified catalyst without using any branching agent. ;SOLUTION: A mixture comprising a polyester carbonate (mixture) (A) having an initial weight-average molecular weight of 500-200,000 and about 15-1,000 ppm, based on A, of a carbonate redistribution catalyst (B) is heated to 180-320°C without using any branching agent to modify the initial polyester carbonate (mixture) by melt equilibration into a polyester carbonate having a molecular weight different from that of A. A comprises a major proportion of structural carbonate units and a minor proportion of structurl units derived from a dihydroxy aromatic compound (particularly bisphenol A) and a dicarboxylic acid (particularly adipic acid or 1,12-dodecanedicarboxylic acid). Various bases and Lewis acids can be used as B. Among them, a 1-4C tetraalkylamonium base is particularly dessirable. To perform the redistribution, a diaryl carbonate may be added as an end capping agent.;COPYRIGHT: (C)1996,JPO
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