β晶型聚丙烯(β-PP)由于其优异的力学性能及其拉伸能形成微孔等特性已成为聚丙烯改性研究的热点。本文综述了近年来β晶型聚丙烯的研究发展状况。介绍了生成β-PP的四种方法,重点说明了添加β成核剂诱导生成β晶型的方法;β成核剂的发展历史、分类及成核效率和成核机理;β-PP的几种超分子结构:β球晶、β六方晶、β横晶、β柱晶;β→α相转变类型及机理;温度、剪切、退火、热历史及不同工艺条件对生成β-PP的影响,为生成高β含量制品提供了参考。并对未来的研究发展趋势做了展望。
β form polypropylene (β-PP) has been a hot topic in modification-PP because of its excellent mechanical properties, forming microhole in drawing and other special properties. This paper reviewsthe development advances in β-PP in recent years. It simply describes four methods of making β-PP, focus on the way of β nucleating agent inducing β form in PP; the history, sorts, efficiency and nucleating mechanism of β nucleating agent ; different supermolecular structures of β-PP: β-spherulite, hedrite, β-Transcrystallinity, β-cylindrite; β→α phase transformation and mechanism; the effect of temperature, shearing, annealing, hot history and processing condition on the β-PP, It provide information for producing high content β form polypropylene. Trends in research of nucleating agents are also presented.