Crystollization and Morphology Central of Polymer Chains in a Nanoscale space

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We have investigated the process of morphological reorganization (crystallization process and melting process) and final morphology for various crystalline-amorphous diblock copolymers and their blends with homopolymers in order to establish the method of morphological control in polymer alloys. The results are summarized as follows :(1) We have found that the final morphology of poly(epsilon -caprolactone)-block-polybutadiene (PCL-b-PB)/poly(epsilon -caprolactone) depends strongly on the phase structure in the melt.(Polymer Journal, 29, 642 (1997))(2) We explained the morphology of poly(epsilon -caprolactone)-block-polystyrene (PCL-b-PS) on the basis of the glass transition temperature Tg of the amorphous block, where the crystallizabiity of the constituent block depends significantly on Tg. (Polymer, 39, 1727 (1998))(3) We investigated qualitatively the melting process of PCL-b-PB by time-resolved small-angle X-ray scattering (SAXS) with synchrotron radiation. The results were compared with the crystallization process of PCL-b-PB and the melting process of crystalline homopolymers, It was found that the melting process of PCL-b-PB was extremely unique. (Polymer Journal, 30, 628 (1998))(4) The morphology formed in PCL- b-PS was investigated by SAXS as a function of the composition in the copolymer, It was found that the crystallinity and final morphology depends intimately on the copolymer composition. (Polymer Journal 30, 968 (1998))(5) We investigated quantitatively the melting process of PCL-b-PB under various conditions and tried to find the melting mechanism in crystalline-amorphous block copolymers, It was found that two factors, nonequilibrium crystallization at Tc and conformational competition between crystalline and amorphous blocks, were important for the melting of PCL-b-PB.(Macromolecules, in press (1999))