申请人:——
公开号:US20020037838A1
公开(公告)日:2002-03-28
A method for manufacturing polycarbonate by melt-polycondensing bisphenol and carbonic acid diester uses as catalyst an alkali metal compound and/or alkaline earth metal compound (a). The catalyst is added to the bisphenol prior to the melt polycondensation, in an effective amount, i.e., the amount of alkali metal compound and/or alkaline earth metal compound (a) that acts effectively as a catalyst, is contained in said bisphenol, and is controlled to have the same catalytic activity as 1×10
−8
to 1×10
−6
mole of bisphenol disodium salt per mole of pure bisphenol A. The method conducts the reaction efficiently from the initial stage in a stable manner to obtain polycarbonate with good color, good heat stability and color stability during molding and the like.
一种通过熔融缩聚双酚和碳酸二酯制造聚碳酸酯的方法,使用碱金属化合物和/或碱土金属化合物(a)作为催化剂。催化剂在熔融缩聚之前被添加到双酚中,添加的量是有效的,即碱金属化合物和/或碱土金属化合物(a)的量作为催化剂是包含在双酚中的,并且被控制为具有与1×10^-8至1×10^-6摩尔双酚二钠盐相同的催化活性。该方法从初始阶段开始有效地进行反应,稳定地获得具有良好颜色、良好热稳定性和成型过程中颜色稳定性的聚碳酸酯。