| 摘要 |
<p>A polycarbonate resin which is obtained by reacting a carbonate material with a dihydroxy compound and in which the ratio of the weight-average molecular weight (Mw) to the number-average molecular weight (Mn) in terms of polystyrene as determined by gel permeation chromatography (Mw/Mn) is 2.2 or lower and the ratio of the viscosity-average molecular weight (Mv) as calculated with the following equations to the number-average molecular weight (Mn') as calculated from the number of molecular ends (Mv/Mn') is 1.40 or lower. θsp/C=[θ]x(1+0.28θsp) [θ]=1.23x10?-4xMv0.83¿. (In the equations, θ¿sp? is the specific viscosity of a methylene chloride solution of the polycarbonate resin at 20°C and C is the concentration of the methylene chloride solution, provided that the methylene chloride solution has a polycarbonate resin concentration of 0.6 g/dl.). The polycarbonate resin has a molecular weight distribution showing that the resin is nearly monodisperse. It is extremely reduced in the emission of oligomer-derived volatiles during thermal molding.</p> |
