用高斯分布法计算非晶态聚合物聚氯乙烯主转变过程中的动态力学弛豫时间谱分布

CALCULATION OF RELAXATION TIME DISTRIBUTION OF α-PEAK IN PVC WITH GAUSSIAN DISTRIBUTION

对非晶态聚合物聚氯乙烯PVC进行不同频率升温扫描的动态力学弛豫谱测量,发现主转变内耗峰(α峰)峰形及其他峰参数均随频率变化。本文根据连续分布谱的理论讨论PVC主转变内耗峰弛豫时间τ的分布情况,并通过高斯分布时方法,计算出PVC主转变弛豫过程中弛豫时间常数τ_0和激活能△H对弛豫时间τ的贡献权重。指出τ_0和△H在PVC主转变过程中都有明显的分布。

Dynamic mechanical loss spectra correspornding to different frequency were measured at ascending temperature for amorphous polymer PVC (a-PVC). It is found that measuring frequency dependance of the parameters of a-peak obviously exists. To determine the contribution of τo or ΔH distribution to τ distribution, on the basis of analysing relaxation time distribution (τ distribution) of α-peak in a-PVC, the parameters of τo and ΔH have been calculated in this paper.