PBT纺丝用切粒相关工艺调整

The process parameters adjustment of the PBT chip production for spinning

针对下游纺丝用户对PBT切粒品质提出的要求,本装置从催化剂用量、酯化阶段温度及内量比、预缩终缩反应温度、终聚釜压力、终缩聚黏度控制方式、黏度控制范围等方面进行调整,有效降低了PBT切粒端羧基值,最低降至18.2 mol/t,同时降低了PBT分子质量分布系数,提高了PBT分子链长的均一性。

In order to meet the PBT chip quality demand of the downstream spinning customer, the plant made a se- ries of adjustment from catalyst, esterifieation temperature, BDO/PTA mole ratio, prepolyeondensation tempera- ture, final polycondensation temperature, vaccum of Disc Ring Reactor （DRR）, the control mode of viscosity in DRR and the control scope of viscosity. The earboxyl end group value of PBT was reduced effectively, and the low- est value was reduced to 18.2 tool/t, and at the same time, the molecular weight distribution coefficient is reduced,which means the PBT molecular chain length are more homogeneous.