A new series of 1, 4-anhydro-3-azido-ribopyranose derivatives was synthesized as functional monomers in order to study effects of the monomer structure on selective ring-opening polymerization behaviors and structures of the resulting polysaccharides. The general formula of the four monomers were written as 1, 4-anhydro-3-azido-3-deoxy-2.O-(p-substituted benzyl)-α-D-ribopyranose (A3A2SBR), in which the substituted group represented methyl (CH₃), hydrogen (H), chloro (CI), and bromo (Br) group. The four monomers were synthesized by reaction of 1, 4-anhydro-3-azido-3-deoxy-2-O-acetyl-α-D-ribopyranose with p-substituted benzyl chlorides or bromides. Selective ring-opening polymerization of the monomers was performed by BF₃•OEt₂ catalyst at -20°_??_40°C to give 3-azido-3-deoxy-2-O-(p-substituted benzyl)-(1→5)-α-D-ribofuranans with _??__n of 1.7×10⁴_??_4.6×10⁴and[α]_D²⁰of+180.1_??_+217.2°. Ring-opening polymerization by SbCl₅ catalyst at-40°C afforded a polymer composed of a mixture of 1, 5-α-and 1, 5-β-ribofuranosidic units. In the selective ring-opening polymerization by BF₃•OEt₂ catalyst, _??__n increased and molecular weight distributions _??__n/_??__w became narrower with changing Hammett sigma constant of the p-substituted groups from negative to positive values in following order: methyl (-1.4), hydrogen (0), chloro (+2.4) and bromo (+2.6) groups. It was revealed that the p-substituted groups with different Hammett sigma constants had a regular effect in the ring-opening polymerization.

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Effects of liquid crystal (LC) on electro-optical (EO) properties and structures of LC/polymer composite (LCPC) films prepared by electron-beam polymerization of several nematic LCs and bifunctional methacrylate monomer were investigated. The bifunctional monomer formed polymer matrix structure of either the aggregate of microspheres or three-dimensional network containing microspheres in LCPC film, depending on a kind of LC. EO properties of the former were governed by properties of LC and relatively good. Those of the latter indicated low response voltage, but a low light-scattering in the absence of a field.

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Changes in fine structure and chemical structure on the surface of poly (ethylene 2, 6-naphthalenedicarboxylate) (PEN) fibers, caused by irradiation with excimer laser, were investigated. The SEM observation showed that the undrawn yarns suffered from ablation on the whole surface, while in the cause of drawn yarns, a fine wavy structure was formed perpendicular to the fiber axes. The XPS analysis of the fiber surface showed that for both undrawn and drawn yarns, the atomic ratio of O_{_??_s}/C_{_??_s} was reduced, that is, the contents of oxygen was reduced. After dyeing with disperse dyestuff at 130°C estimated the depth of the dyed color, as the ablation energy increases, penetrate the dyestuff inside the fiber and is darker in color. The ablated surface layer of the drawn yarns was partly converted to non-crystalline form.

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Bisphenol A polyarylate is known as an amorphous high performance polymer with excellent properties. Though the polyarylate composed of bisphenol A and terephthalic/isophthalic acids is an amorphous polymer, we found that the polyarylate oligomer crystallized when the swelled oligomer gel was contacted with acetone. Solid-state polymerization of the crystallized polyarylate proceeded at a much lower temperature than that for the melt condensation. This solid-state polymerization process supplies us the new route for the production of polyarylate with excellent color.

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The relationship between the surface coverage ratio of rosin sizing agents on pulp fiber and the liquid absorption characteristics was examined. The surface coverage ratio of rosin on paper sheets was estimated by the degree of surface carbon atom concentration, which was obtained from the ESCA angle-dependent technique. The Stöckigt sizing degree, the rate of change in contact angle with the elapse of time and the magnitude of slope of the line in dynamic contact angle were adopted as the liquid absorption characteristics.
In the case of the emulsion type rosin, the liquid absorption characteristics changed notably by heat treatment in comparison to those in the soap type rosin.
The Stöckigt sizing degree increased with the surface coverage ratio, and the rate of change in contact angle with elapse of time and the magnitude of slope to the line in dynamic contact angle decreased with the increase in the surface coverage ratio. Furthermore, the rate of change in contact angle and the magnitude of slope to the line in dynamic contact angle decreased remarkably by heat treatment.

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