Method for preparing branched polycarbonate with continuous two-phase interface phosgene method
US9683078B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Sep 9, 2013 |
| Grant date | Jun 20, 2017 |
| Priority date | — |
| Expiry date | Sep 9, 2033 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC08G64/24
- WIPO fieldMacromolecular chemistry, polymers
- WIPO sectorChemistry
Abstract
The present invention relates to a method for preparing branched polycarbonate with a continuous two-phase interface phosgene method. Firstly, an aqueous solution of alkali metal hydroxide with triphenol and polyphenol dissolved therein reacts with a certain amount of phosgene in the present of inert organic solvent to prepare a prepolymer, and then a coupling reaction is performed among the prepolymer, an aqueous solution of alkali metal hydroxide with bisphenol and phosgene dissolved therein to finally obtain a polycarbonate resin. The method can avoid a cross-linking reaction, reduce the cost and improve the quality of the product, while improving the conversion ratio of the branching agent and the branching degree of the product.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.