Mechanism of Polymer Crystallization-Material Design Controlled by High Order Structure Formation

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We organized five symposiums including international symposium held on 2002 at Mishima. The numbers of participants were more than 150 persons including about 30 oversea participants. These contributed papers were published in the special issue of Journal of Macromolecular Science volume B42 in 2003. In this research project, we have published 213 papers, including 113 general papers, 6 review articles, 4 books, 3 patents and oral presentation for over sea conferences (105) and for Japanese conference (244).The main research results were as follows, It was found that the spinodal decomposition type microphase separation actually occurs in the induction period, owing to orientational fluctuations of the stiff segments. Topological mechanism of the nucleation of polymers has been studied. The direct evidence was shown for the first time that nuclei have been formed during the induction period of the nucleation by means of Small angle X-ray scattering. The molecular weight dependence of t … More he nucleation rate was expressed by power law. The nucleation rate was strongly dependent on wetting force between polymer sample and substrate surface and crystal lattice. It was found that when poly(ethylene oxide) was crystallized on alkali halides, the diffusion-limited aggregates (DLA) were formed. It is the first case of DLA, which was identified in polymer crystallization. The temperature dependence of nucleation rate and growth rate showed bell-shaped curves showing clear maximum points of Imax and Gmax. The MW dependence of Imax and Gmax are scaled and expressed as 1 and -0.5 power of MW, respectively for a chain folding crystallization. Molecular pathways to polymer crystallization and the structures of crystal-melt interfaces were investigated by molecular dynamics simulation. We clearly observe the growth of stacked chain-folded lamellae from the substrates. The growing lamellae have a definite tapered shape, and they show marked thickening growth along the chain axis as well as usual growth perpendicular to it. Crystallization rate of Po]y(carbonate) (PC) in general is very slow, however its rate was accelerated by polymer blending with poly(ethylene oxide) (PEO). During crystallization of the blends, spinodal decomposition was observed and spherulite of PC was observed in PC rich phase. The crystallization of PC was controlled by up-hill diffusion during liquid-liquid phase separation in the polymer blends. Bi-and uni-axial drawing of poly(ethylene terephthalate) (PET) and poly(ethylene 2,6 naphthalene dicarboxylate) (PEN) were performed at various strain rates and temperatures. On-line measurements of drawing stress and birefringence were carried out under several drawing conditions. The stress-optical rule (SOR) was applicable at low birefringence, and the stress-optical coefficient obtained for drawing process was similar to the reported values. Less