摘要:
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: in the presence of catalyst to form an oligomer comprising less than 2,000 ppm of an ester-linked terminal group, and melt polymerizing the oligomer to form a polycarbonate. Use of specific reaction conditions produces a polycarbonate having an Mw of greater than or equal to 25,000 g/mol as determined by gel-permeation chromatography relative to polystyrene standards. Polycarbonates comprising units derived from the multifunctional compound, including homopolycarbonates, aliphatic copolycarbonates further comprising units derived from an aromatic dihydroxy compound, and aliphatic polycarbonate-polyesters, are also disclosed, as are a thermoplastic composition and an article including the disclosed polycarbonates.
摘要:
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.
摘要:
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.
摘要:
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.
摘要:
A method of producing a polycarbonate is provided. In an embodiment of the present invention the method includes the steps of: (i) introducing to a melt polymerization reactor system a reaction mixture having a first dihydroxy compound and an acid stabilizer, a carbonate source, and a polymerization catalyst system containing K2HPO4; and (ii) allowing the reaction mixture to polymerize thereby forming polycarbonate.
摘要:
A reactor system for producing polycarbonate includes a surface area in contact with a reaction mixture. The reaction mixture comprises a melt transesterification catalyst, a dihydroxy compound, a diaryl carbonate, and an phenolic byproduct. The surface area in contact with the reaction mixture contains one or more welds joining reactor system parts. All welds in contact with the reaction mixture join reactor system parts made from the same type of metal. If a filler metal is contained in the weld, the filler metal is made from the same type of metal as the metal parts joined by the weld.
摘要:
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.
摘要:
A reactor system for producing polycarbonate includes a surface area in contact with a reaction mixture. The reaction mixture comprises a melt transesterification catalyst, a dihydroxy compound, a diaryl carbonate, and an phenolic byproduct. The surface area in contact with the reaction mixture contains one or more welds joining reactor system parts. All welds in contact with the reaction mixture join reactor system parts made from the same type of metal. If a filler metal is contained in the weld, the filler metal is made from the same type of metal as the metal parts joined by the weld.
摘要:
A method of making a polycarbonate is described. The method comprises reacting an activated diaryl carbonate and a dihydroxy compound at a reaction temperature in a reactor to form a reaction mixture wherein the reactor comprises a heated cover and an open space between the cover and the reaction mixture. The dihydroxy compound comprises a vapor pressure greater than or equal to 0.01 kiloPascals at the reaction temperature and the temperature of the open space in the reactor, the temperature of the cover, or the temperature of the open space and the cover is greater than or equal to the melt temperature of the monomer having the highest melt temperature.
摘要:
A method of producing a polycarbonate is provided. In an embodiment of the present invention the method includes the steps of: (i) introducing to a melt polymerization reactor system a reaction mixture having a first dihydroxy compound and an acid stabilizer, a carbonate source, and a polymerization catalyst system containing K2HPO4; and (ii) allowing the reaction mixture to polymerize thereby forming polycarbonate.