摘要
对固相缩聚的机理和影响因素进行了介绍。认为聚对苯二甲酸丁二酯 ( PBT)是一种重要的工程塑料 ,高的分子质量使其性能得到提高。作为生产 PBT高粘切片的有效方法 ,固相缩聚依赖于化学 (可逆化学反应 )和物理 (小分子的扩散 )
When polybutylene terephthalate (PBT) is used as engineering plastic materials, the molecular weight plays an important role in order to reach the desired properties or have suitably high melt viscosity Solid state polycondensation (SSP) processes, for preparing particular high molecular weight PBT, are carried out by heating the low molecular weight prepolymers in the form of chips in a stream or inert gas or under vacuum at a temperature above the polymer glass transition but below the melting point. The SSP rate may depend on chemical or physical processes or both, being determined by the slow process. The main factors that affect SSP include reaction temperature and time, particle size, initial molecular weight, number and type of chain end groups, catalyst employed, crystallinity, and the technique used to remove byproducts.
出处
《合成技术及应用》
2000年第2期31-34,共4页
Synthetic Technology & Application
关键词
固相缩聚
分子质量
PBT
塑料
polybutylene terephthalate
solid state polymerization
molecular weight
