摘要:
A method of increasing the branching and polydispersity of a polycarbonate includes the steps of: (a) including in the polycarbonate at least one species of an alkyl substituted monomer, and (b) treating the polycarbonate at an elevated temperature and for a sufficient time to increase the branching and polydispersity relative to an otherwise equivalent polycarbonate without alkyl substituents.
摘要:
Disclosed herein is a process to prepare a poly(carbonate-co-urea) copolymer comprising reacting in the melt: (a) a dihydroxy reaction component comprising a dihydroxy compound, (b) a diaryl carbonate reaction component comprising a diaryl carbonate, (c) a urea reaction component comprising a urea compound in the presence of (d) a transesterification catalyst during at least part of the reaction and removing a phenolic byproduct to produce a poly(carbonate-co-urea) copolymer, wherein the urea and dihydroxy compounds are reacted in a molar ratio: (total moles of urea compound)/((total moles of urea compound)+(total moles of dihydroxy compound)) of less than or equal to 0.5.
摘要:
Disclosed herein is a poly(carbonate-co-urea-co-ester) copolymer comprising incorporated urea compound, dihydroxy compound and diacid compound residues. Also disclosed herein is a poly(carbonate-co-urea) copolymer comprising incorporated urea compound and dihydroxy compound residues.
摘要:
Disclosed herein is a process to prepare a poly(carbonate-co-urea) copolymer comprising reacting in the melt: (a) a dihydroxy reaction component comprising a dihydroxy compound, (b) a diaryl carbonate reaction component comprising a diaryl carbonate, (c) a urea reaction component comprising a urea compound in the presence of (d) a transesterification catalyst during at least part of the reaction and removing a phenolic byproduct to produce a poly(carbonate-co-urea) copolymer, wherein the urea and dihydroxy compounds are reacted in a molar ratio: (total moles of urea compound)/((total moles of urea compound)+(total moles of dihydroxy compound)) of less than or equal to 0.5.
摘要:
An injection molded article comprising a polycarbonate composition. The polycarbonate composition is scratch resistant, flame retardant, has a low chlorine and bromine content and is dark colored.
摘要:
Disclosed herein is a poly(carbonate-co-urea-co-ester) copolymer comprising incorporated urea compound, dihydroxy compound and diacid compound residues. Also disclosed herein is a poly(carbonate-co-urea) copolymer comprising incorporated urea compound and dihydroxy compound residues.
摘要:
An injection molded article comprising a polycarbonate composition. The polycarbonate composition is scratch resistant, flame retardant, has a low chlorine and bromine content and is dark colored.
摘要:
A method of increasing the branching and polydispersity of a polycarbonate includes the steps of: (a) including in the polycarbonate at least one species of an alkyl substituted monomer, and (b) treating the polycarbonate at an elevated temperature and for a sufficient time to increase the branching and polydispersity relative to an otherwise equivalent polycarbonate without alkyl substituents.
摘要:
Windows and other articles made from dimethyl bisphenol cyclohexane (DMBPC) polycarbonate exhibit enhanced scratch resistance properties and Mw degradation resistance properties as compared to traditional polycarbonates. Such windows and other articles made from DMBPC polycarbonate can be used in various applications including buildings, particularly in agricultural environments and in electronic devices.
摘要:
A method for preparing a molded article includes the steps of (a) obtaining a polycarbonate resin and (b) molding the polycarbonate resin. The polycarbonate resin is made by a transesterification reaction using an activated diaryl carbonate such that the polycarbonate is susceptible to the formation of internal ester linkages (IEL). The method occurs with the proviso that the polycarbonate resin, the molding conditions or both are selected to control the amount of IEL formed during the molding process to a level of less than 0.4 mol %.