Patent application number | Description | Published |
20080287640 | PROCESS FOR THE PRODUCTION OF POLYCARBONATE USING AN ESTER SUBSTITUTED DIARYL CARBONATE - A method of preparing polycarbonate includes a steps of providing a melt reaction mixture and allowing the melt reaction mixture to react to build molecular weight, thereby preparing the polycarbonate. The melt reaction mixture has a dihydroxy compound, an ester substituted diaryl carbonate mixture, and a melt transesterification catalyst where the ester substituted diaryl carbonate mixture may contain acid-substituted phenol. The method also includes the step of adjusting the molar ratio of acid-substituted phenol, if present, to melt transesterification catalyst (acid-substituted phenol/catalyst) in the melt reaction mixture to an amount of less than 10. | 11-20-2008 |
20090105443 | ALIPHATIC POLYCARBONATES, METHODS OF MAKING, AND ARTICLES FORMED THEREFROM - A method of making a polycarbonate is described. The method comprises melt reacting an ester-substituted diaryl carbonate and a multifunctional compound of the formula: | 04-23-2009 |
20090286952 | METHOD OF FORMING POLYCARBONATE - A method of forming polycarbonate includes the steps of introducing a plurality of reaction components to a reactor operating under melt polymerization conditions and removing ester-substituted phenol from the reactor. The plurality of reaction components include a dihydroxy compound, an ester-substituted diaryl carbonate, and a melt transesterification catalyst. The reaction components are introduced in a plurality of reaction component streams. A first reaction component streams includes a melt transesterification catalyst dissolved or suspended in a liquid carrier containing an ester-substituted phenol. The composition of the first reaction component stream is selected such that ester-substituted phenol is not generated as a reaction product in the first reaction component stream. | 11-19-2009 |
20120296064 | METHODS AND SYSTEMS FOR THE CONTINUOUS ADDITION OF BRANCHING AGENTS INTO MELT POLYCARBONATE POLYMERIZATION PROCESSES - This disclosure relates generally to methods for the manufacture of melt polymerized branched polycarbonates. The methods disclosure herein introduce branching agent into the melt process as a dissolved component in a solution comprised of a solvent and dissolved branching agent. Also disclosed are systems and apparatuses for performing the disclosed methods. | 11-22-2012 |