Dynamic light scattering studies have been made on dilute solutions of narrow-distribution polystyrenes in benzene at 30 °C over a wide range of qRa (=Xl/2). The intensity autocorrelation function has been analyzed with the histogram method. The analysis made it possible to estimate the translational diffusion coefficient D, the effective decay rate Fe, and the intensity of the translational diffusion motion relative to the total intensity P0/P at finite polymer concentration. Those quantities have been linearly extrapolated to infinite dilution to obtain values characteristic of a single swollen coil. It has been found that the hydrodynamic radius fiH calculated from D0 increases in proportion to Mw°55 and expansion factors aH and aa have different functional dependences on the excluded volume parameter z. It has also been found that, for X1/2 » 1, the quantity (TJ^,/(q3kBT/ 0) approaches a constant value which is less than the theoretical value by 25%. The X dependence of (P0/P)^o suggests that the internal motion is suppressed in a single swollen coil to some extent in comparison with that in a Gaussian coil. The concentration dependence of D is also briefly discussed.

We developed new photo alignment materials based on chalconyl structure with high sensitivity to near UV light. Poly(4-methacryloyloxy chalcone), PM4Ch, and its derivatives exhibited good LC alignment upon near TJV exposure. The photoreactivity of chalconyl structure was high because due to longer wavelength of UV absorption. The high sensitivity of PM4Ch, compared with Poly(4'-methacryloyloxy chalcone), PMCh, could be explained by the suppression of isomerization and/or by the alignment capability of the side chain structure.

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