Crystallization in polymer blends

We investigated the morphology development in poly(vinylidene fluoride)/poly(methyl methacrylate) blend and isotactic polypropylene/partially hydrogenated oligo(styrene-co-indene) blend by using polarized microscope, small angle x-ray scattering, light scattering, dielectric relaxation and TEM observation. The analyses of these results revealed the exclusion effect of the noncrystalline component on the crystallization; (1) two-step diffusion mechanism, i.e., mutual-diffusion process for the secondary nucleation process and self-diffusion for the surface spreading process, (2) partial exclusion of the noncrystalline component from the interlamellar region in the coarse spherulite, (3) growth of the coarse spherulite by decreasing the degree of ordering, (4) existence of large amount of the noncrystalline component at the crystal-amorphous interphase and (5) unique lamellar morphology.