发明授权
US4644053A Cyclic polycarbonate oligomers and methods for their preparation and use
失效
环状聚碳酸酯低聚物及其制备和使用方法
- 专利标题: Cyclic polycarbonate oligomers and methods for their preparation and use
- 专利标题(中): 环状聚碳酸酯低聚物及其制备和使用方法
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申请号: US704122申请日: 1985-02-22
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公开(公告)号: US4644053A公开(公告)日: 1987-02-17
- 发明人: Daniel J. Brunelle , Thomas L. Evans , Thomas G. Shannon , David A. Williams
- 申请人: Daniel J. Brunelle , Thomas L. Evans , Thomas G. Shannon , David A. Williams
- 申请人地址: NY Schenectady
- 专利权人: General Electric Company
- 当前专利权人: General Electric Company
- 当前专利权人地址: NY Schenectady
- 主分类号: C08G64/26
- IPC分类号: C08G64/26 ; C08G64/30 ; C08G75/28 ; C08G63/62
摘要:
Cyclic polycarbonate (or thiol analog) oligomer mixtures are prepared by the reaction of bishaloformates or their thio analogs or mixtures thereof with dihydroxy or dimercapto compounds, with alkali metal hydroxides and various amines. The oligomer mixtures may be converted to polycarbonates or their thiol analogs by a method which is particularly adaptable to integration with polycarbonate processing operations.
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