摘要
用自制高压装置使聚丙烯（ＰＰ）在０．７７ＧＰａ、２５０℃下融体结晶，经ＷＡＸＤ分析所得结晶试样为γ晶型ＰＰ。并用高温ＷＡＸＤ和ＤＳＣ研究了γ－ＰＰ在热作用下向α－ＰＰ转变的过程及机理。γ－ＰＰ在远低于其熔点的温度下发生向α－ＰＰ转变，而不是γ－ＰＰ先熔融，再重新结晶成α－ＰＰ，即这是一种固～固转变，且这种γ－α转变受升温速率的影响很大，γ－α晶型转变只发生在较低的升温速率，在高的升温速率下，不发生γ－α晶型转变。
γ form polypropylene(PP) was obtained from crystallized at 250 ℃ and 0.77 GPa. The phase transition of γ PP has been studied via WAXD and DSC, γ PP is transformed to α PP at far below its melting point, which indicates it is a solid solid transition process. γ α solid solid phase transition is heating rate dependent. There is no γ α solid solid phase transition when heating rate is too fast.
出处
《高分子材料科学与工程》
EI
CAS
CSCD
北大核心
1999年第4期69-71,共3页
Polymer Materials Science & Engineering
基金
国家自然科学基金
关键词
固转变
聚丙烯
结晶
γ晶型
γ PP, solid solid phase transition, α PP
