Patent ID: 6262185
Filing Date: 2001-07-17
Classification: C08G,C08J,C08L,G02B,Y10T

Abstract:
A thermoplastic polyester molding material containingA) from 80 to 100% by weight of a polyalkylene arylate having a half-width of the crystallization isotherms of .ltoreq.5.degree. C.B) from 0 to 20% by weight of further additives, the percentages by weight of components A) and B) summing to 100%, produced by a process in which,a) in a first stage, an aromatic dicarboxylic acid or an ester or ester-forming derivative thereof is esterified or transesterified with a molar excess of a dihydroxy compound, to which first a catalyst and then an alkali metal compound or alkaline earth metal compound has been added,b) in a second stage the transesterification or esterification product obtained according to a) is subjected to precondensation andc) in a third stage, the product obtained from b) is subjected to polycondensation to a VN of at least 158 ml/g, whereinstage a) and b) of the process are carried out in at least two temperature zones and, if present, component B) is added to the melt before or after the polycondensation c) and before cooling.