摘要
在不同的拉伸温度下对β晶型全同聚丙烯的晶相转变进行了研究,用X 射线衍射扫描和平板照相法观测到在拉伸样品过程中,没有产生β晶型的择优取向,而是发生β晶型向α晶型的转变,进一步产生新生的α晶型的取向.这与一般结晶高聚物在拉伸时首先产生原晶型的取向不同.拉伸温度越高,拉伸比越大,这种β晶型向α晶型的转变也越容易发生和进行的越完全,而且α晶型在c 轴的取向度越高.
Studies on the crystal phase transition of the β form of isotactic polypro-pylene in drawing at various temperature by wide angle X ray photograph anddiffraction spectroscopy.Results demonstrate that drawing β crystal polypropy-lene introduces transition of β crystal into C-axis oriented α crystal in steadof formation of oriented β crystal.The higher the drawing temperature and/orthe greater the lengthening ratio the easier,the more will be the β→α tran-formation and the higher will be the orientability of C-axis oriented α crystal.
