发明授权
- 专利标题: Salts of organic phosphates as catalysts for melt polycarbonate
- 专利标题(中): 有机磷酸盐作为熔融聚碳酸酯的催化剂
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申请号: US10007346申请日: 2001-10-25
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公开(公告)号: US06583258B1公开(公告)日: 2003-06-24
- 发明人: John Patrick Lemmon , Ronald James Wroczynski
- 申请人: John Patrick Lemmon , Ronald James Wroczynski
- 主分类号: C08G6400
- IPC分类号: C08G6400
摘要:
The present invention relates to a synthetic method in which one or more diaryl carbonates is reacted with one or more dihydroxy aromatic compounds in the presence of a transesterification catalyst under melt polymerization conditions to afford a product polycarbonate. The transesterifcation catalysts used according to the method of the present invention are alkali metal salts and alkaline earth metal salts of organic phosphates in combination with tetraalkylammonium or tetraalkylphosphonium compounds which serve as co-catalysts. The organic phosphate derivative adenosine 5′-monophosphate disodium salt was shown to possess excellent activity as a transesterifcation catalyst for the preparation of polycarbonate under melt polymerization conditions. The catalysts employed according to the method of the present invention provide polycarbonates having substantial molecular weight (Mn˜8000-10000 daltons) and reduced levels of Fries rearrangement product relative to conventionally prepared melt polycarbonate having a similar molecular weight.
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