The Study Of Crystallization Behaviors In Trans-/CIS-Polyisoprene Blends

As one of the most important factors, crystallization behavior influences the phase structure and mechanical properties. This thesis focused on the trans-/cis-polyisoprene blends. The isothermal and non-isothermal crystallization behaviors of the blends were studied systematically.1:The isothermal crystallization behaviors of TPI/CPI blends were researched with DSC, the crystallization morphology and kinetics were also studied by PCOM/POM and WAXD. It was found that the crystallization rate of TPI/CPI blend was obviously decreased with the increase in CPI component, while the normalized crystallinity of TPI phase increased. The crystal form of TPI in CPI/TPI blends were also significantly influenced by CPI component. Compraring with the neat TPI, the CPI content promoted the formation of β-TPI crystals and inhibited the formation of a-TPI crystals during the isothermal crystallization process.2:The non-isothermal crystallization behaviors of TPI/CPI blends were studied by DSC. It was found that the MO theory can describe the non-isothermal crystallization behaviors of TPI/CPI blends well. The kinetic parameter F(T) increased with the CPI content, which means that the CPI content can reduce the non-isothermal crystallization rate. During the non-isothermal crystallization, the P-TPI crystals increased with improving the cooling rate. During the non-isothermal crystallization, the incorporation of CPI component promoted the formation of β-TPI crystals and inhibited the formation of a-TPI crystals.