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研究了温度对ＰＶＣ断裂伸长率、拉伸强度及加热形变量（针入度）的影响，发现与未增塑ＰＶＣ相类似，增塑ＰＶＣ在９０℃左右出现断裂伸长率最大值；增塑ＰＶＣ的形变量随ＰＶＣ聚合度（结晶度）的增加而减小，软化温度则上升。对于退火处理的增塑ＰＶＣ，形变在退火温度所对应的重结晶熔融温度范围出现转折。认为以上实验结果与增塑ＰＶＣ中微晶交联网络结构的存在及其在升温条件下的破坏有关，提出了增塑ＰＶＣ的微晶交联结构物理模型。根据经典的橡胶弹性理论，计算了交联网络中交联点之间平均分子量（Ｍｃ），发现Ｍｃ随ＰＶＣ聚合度（结晶度）的增加而减小。
The effects of temperature on the elongation at break, tensile strength and heat deformation (penetration) of PVC were studied. It was found that the plasticized PVC had the highest elongation at break at 90 ℃, similar to that of unplasticized PVC. Plastic PVC deformation with the degree of polymerization of PVC (crystallinity) decreases, the softening temperature increases. For the annealed plasticized PVC, the deformation occurred in the range of recrystallization melting temperature corresponding to the annealing temperature. It is considered that the above experimental results are related to the existence of the microcrystalline crosslinked network structure in plasticized PVC and its damage under the conditions of elevated temperature. A physical model of microcrystalline crosslinked structure of plasticized PVC is proposed. According to the classical rubber elasticity theory, the average molecular weight (Mc) between crosslinking points in the crosslinked network was calculated and it was found that Mc decreases with the increase of the degree of polymerization (crystallinity) of PVC.