The isothermal crystallization behaviors of natural eucommia ulmoides gum and synthetic trans-1
4-polyisoprene were comparatively studied by means of DSC and POM. The results of DSC and POM indicated that EUG and TPI exhibited different nucleation and growth mechanism. EUG was mainly homogeneous nucleation
while TPI was heterogeneous nucleation. Isothermal crystallization behavior of EUG was more sensitive to temperature. When isothermally crystallized at a low temperature(28℃)
the crystallization rate of EUG was significantly higher than that of TPI; while when isothermally crystallized at relative higher temperatures(31℃~43℃)
the crystallization rate of EUG was less than that of TPI obviously. The crystallization activation energy of EUG(147.2kJ/mol) was higher than that of TPI(114.8kJ/mol). EUG formed mainly
β
spherulites and TPI was the
α
and
β
spherulites coexist when isothermal crystallization from melt at 37℃. In addition
the collision between spherulites appeared early for TPI due to the heterogeneous nucleation.