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We develop the exact WKB analysis of the PII hierarchy introduced by Gordoa et al. [5] in this paper; our particular interest is in the relation between the Stokes geometry of a higher order Painleve equation in the hierarchy and that of its underlying Lax pair. An important observation is that Stokes curves of the Painleve equation may cross, reflecting the higher order character of the equation, and in a neighborhood of the crossing point an unexpected degeneracy of the Stokes geometry of the Lax pair may occur along a curved ray emanating from the crossing point.

Three-dimensional (3D) image patterns of phase-separated poly(methyl methacrylate) (PMMA)/poly(styrene-ran-4-bromostyrene) (PS-Br) blends heated at 180°C for 6, 8, and 10 h were observed by 3D NMR microscopy with 3D X-ray microscopy in order to characterize the 3D structure of the polymer blends using a standard 3D reconstruction protocol program for obtaining the 3D digital array of the PS-Br/PMMA morphologies. The phase-separated structure of the polymer blends in several 10-μm scales was reasonably characterized. The phase-separated structure of polymer blends by 3D NMR images was quantitatively consistent with that by 3D X-ray images. It can be said that 3D NMR microscopy is a very useful means for analyzing the 3D structure of phase-separated polymer blends as well as 3D X-ray images. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 103: 470–475, 2007

Poly(butylene terephthalate) has two crystalline forms of α and β. The α form is more stable and is transformed into the β form by stretching. The α↔β transition stress was measured at various temperatures with the use of an X-ray diffraction system with imaging plates, and the relationship between the transition stress and temperature was obtained. Further, using the X-ray diffraction system, the drawing behavior of the nearly amorphous, undrawn polymer film was observed by taking up dynamically a series of X-ray diffraction patterns while a film was being drawn. The α form never occurred during drawing at any temperature because the stress to draw the film exceeded the α→β transition stress. © 2000 John Wiley & Sons, Inc. J Polym Sci B: Polym Phys 38: 838–845, 2000