PVC退火过程中的熵变计算

CALCULATION OF ENTROPY CHANGE OF PVC IN ANNEALING PROCESS

非晶高聚物在玻璃化转变点（Ｔｇ）以下时效敏感区退火将引起内部有序度的变化和结构熵值的降低，并产生动态力学弛豫性能的非线性变化［１］，因此通过宏观测量对材料结构熵的计算是有意义的．本文引用了结构温度的概念，利用差热分析仪（ＤＳＣ）测量不同退火条件下，非晶高聚物ＰＶＣ的焓变量来间接得到其结构熵变。

Enthalpy change( H) corresponding to different annealing temperaturewas systematically was measured by using DSC in amorphous polymer PVC (a-PVC). By introducing a concept on structure temperature(θ), entropy change △(S) was easily obtained. On the basic, the change of glass structure in a-PVC corresponding different annealing temperature can be analysised by calculating △S.Correspondent: LI Jian, Institute of Solid State Physics, Chinese Academy of Scinece, Hefei 230031