Masaki Takata

Abstract: Crystallization behavior of polyethylene (PE) on silicon wafers in solution casting processes has been successfully traced by time-resolved grazing-incidence small-angle and wide-angle X-ray scattering (GISWAXS) measurements utilizing synchrotron radiation. A p-xylene solution of PE kept at ca. 343 K was dropped on a silicon wafer at ca. 298 K. While the p-xylene evaporated naturally from the dropped solution sample, PE chains crystallized to be a thin film. Raman spectral measurements were performed simultaneously with the GISWAXS measurements to evaluate quantitatively the p-xylene the dropped solution contained. Grazing-incidence wide-angle X-ray scattering (GIWAXS) patterns indicated nucleation and crystal growth in the dropped solution and the following as-cast film. GIWAXS and Raman spectral data revealed that crystallization of PE was enhanced after complete evaporation of the p-xylene from the dropped solution. The [110] and [200] directions of the orthorhombic PE crystal became relatively parallel to the wafer surface with time, which implied that the flat-on lamellae with respect to the wafer surface were mainly formed in the as-cast film. On the other hand, grazing-incidence small-angle X-ray scattering (GISAXS) patterns implied formation of isolated lamellae in the dropped solution. The lamellae and amorphous might alternatively be stacked in the preferred direction perpendicular to the wafer surface. The synchrotron GISWAXS experimental method could be applied for kinetic study on hierarchical structure of polymer thin films.

TL;DR: In this paper, the nuclear density distributions for both paraelectric and ferroelectric phases of KDP were obtained by the software system named remedy, which is a combined program system of Rietveld refinement, rietan -98, and the maximum entropy method, mend for neutron diffraction.

TL;DR: In this article, the authors investigated the melt-isothermal crystallization behavior for isotactic polypropylene (iPP) by means of time-resolved simultaneous measurements of small-angle X-ray scattering (SAXS) and wide-angle x-ray diffraction (WAXD) using synchrotron radiation source in SPring-8.

TL;DR: In this paper, Epitaxial crystallization onto a directionally crystallizable organic solvent, 1,3,5 trichlorobenzene, was applied to polymer blends containing regioregular poly(3-hexylthiophene-2,5-diyl) (P3HT) a...