杜仲橡胶与合成反式1,4-聚异戊二烯非等温结晶性能对比

Comparison on Non-isothermal Crystallization Performance of Eucommia Ulmoide Gum and Trans 1,4-Polyisoprene

通过红外光谱、核磁共振和凝胶渗透色谱等测试手段表征杜仲橡胶(EUG)和合成反式1,4-聚异戊二烯(TPI)的化学组成和结构差异,进而采用差示扫描量热仪和偏光显微镜研究二者的非等温结晶性能。结果表明:EUG中存在极性端基酯基而TPI无;二者的反式1,4-结构含量和相对分子质量相差不大,但EUG的相对分子质量分布略窄于TPI;在相同降温速率下,TPI的初始结晶温度和最大结晶速率的结晶温度均高于EUG,但EUG的结晶速率较快,结晶扩散活化能较高。

The chemical composition and structure difference of eucommia ulmoide gum （EUG） and trans 1, 4-polyisoprene （TP1） were characterized by means of infra-red spectrum, nuclear magnetic resonance and gel permeation chromatography. Their non-isothermal crystallization properties were investigated by differential scanning calorimeter and polarized light microscope. The results showed that, there were polar ester end groups in EUG but not in TPI. The content of trans 1, 4-structure and molecular weight were similar, but the molecular weight distribution of EUG was slightly narrower than that of TPI. When the cooling rate was the same, the temperature of initial crystallization and the maximum crystallization rate of TPI were higher than those of EUG,respectively,but the crystallization rate and diffusion activation energy of EUG were higher.