| abstract |
A method for preparing a modified polycarbonate comprising i) providing a polycarbonate prepared by the melt transesterification of a bisphenol and a diaryl carbonate preferably having a Fries branching level of from 750 to 2000 ppm, ii) combining said polycarbonate and from 0.10-0.75 wt. %, based on the amount of polycarbonate, of a modifier, iii) reacting said modifier and said polycarbonate in molten state at a temperature of from 250-300° C. and a reaction time of at least 30 seconds so as to form the modified polycarbonate, wherein said modifier is a styrene-(meth)acrylate copolymer containing glycidyl groups and having i) from 250 to 500 gram epoxy groups per mol and ii) a weight average molecular weight of from 3000 to 8500 g/mol, and wherein said modified polycarbonate has a transmittance of at least 85% and a haze of at most 5% as determined in accordance with ASTM D1003-13 on an injection moulded sheet having a thickness of 3 mm. |