The effects of prehistory has been studied by the measurements of rheological properties of polypropylene melts and of physical properties of as spun filaments obtained from two samples having different prehistory. One (sample A) is prepared by quenching the melt screw extrudated. The other (sample B) is prepared by the solution crystallizing from the dilute solution in xylene. These samples are well characterized by means of x-ray diffraction and dilatometry. The results of the melt viscosity, die swell and spinnability of the melt show differences according to the differences in the prehistory: the melt properties are affected by the difference in entanglement between sample A and sample B. It is found from the measurements of thermal shrinkage and tensile testing that as spun filament A having certain prehistory has a larger fraction of tie chain and that as spun filament B free from the prehistory is rich in the fold type crystal fraction.

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The crystallization of poly (vinyl alcohol) (PVA) from the aqueous solution containing ethylene glycol (EG) was carried out under a steady-state flow. The extent of crystallization was maximum at EG content, ca. 10 vol.% and was zero at 30 vol.% at 30°C. Moreover, the effects on the yield of the precipitate of the adsorption of PVA molecules to the solution surface and the dissolved state of PVA molecule in the solvent mixture were described.

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The homogeneous silylation of dissolved cellulose in a PF-DMSO system is investigated and some physical properties of the products are examined. Although the trimethylsilyl derivatives of cellulose have been prepared under heterogeneous conditions only after prolonged reaction times at high temperatures, such as 7 hrs at 150-160°C, the homogeneous silylation of pre-methylolated cellulose at room temperature goes essentially to maximum substitution within 15min. In analogy with the general case of the heterogeneous silylation of cellulose, persilylation of cellulose or methylol cellulose does not occur under these homogeneous reaction conditions; at the most 80% of the hydroxyl protons are replaced by trimethylsilyl groups. The reaction product obtained is (cellulose oligo-oxymethylene ether) trimethylsilyl ether (CSME) in which the chain length of the pendant oligo-oxymethylene is dependent on the conditions of dissolution of cellulose in the PF-DMSO system. The reaction products are characterized by IR, ¹H-NMR and ¹³C-NMR spectroscopies. Although the trimethylsilyl cellulose is soluble only in aromatic and chlorinated solvents, CSME is soluble not only in these solvents but also in esters and ketones. The solubility of CSME in organic solvents is enhanced with an increase in the chain length of the pendant oligo-oxymethylene introduced. The thermal properties of the polymer also change with the introduction of the pendant oligo-oxymethylene. By selecting the conditions of dissolution of cellulose in a PF-DMSO system, silylated cellulose derivatives with desirable T_g and T_m can be obtained.

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Monoaminodeoxystarch (6) having 0.92 as the degree of substitution by amino group was prepared by p-toluenesulfonylation of soluble starch, followed by the reaction with sodium azide, O-aceylation to impart solubility, and the reduction with lithium aluminum hydride. 6-Amino-6-deoxy-D-glucose was found as a main product in the hydrolyzate of 6. Diaminated starch (12) having 1.60 as the degree of substitution by amino group was prepared by p-toluenesulfonylation, followed by the reaction with sodium azide, and the reduction with lithium aluminum hydride.

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The sorption and diffusion of mono-, di- and trisulfonic acid dye in Nylon 6 from their infinite dyebaths at 50°C and pH2.2 adjusted with hydrochloric acid have been discussed in the light of the dual sorption and diffusion model. The dyes are Orange II (C. I. Acid Orange 7, Dye I), Sunset Yellow (C. I. Food Yellow 3, Dye II) and a trisulfonic acid dye (Dye III) prepared from sulfanilic acid and R acid. Partition coefficient, K_p decreased, while Langmuir type sorption constant, K_L increased, with the introduction of sulfonic acid group into these dyes. The diffusivity of the adsorbed species (L) is found to be of primary importance in determining the concentration dependence of the apparent diffusion coefficient.

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Cotton fabrics were chemically modified to allow transfer printing with disperse and cationic dyestuffs. Acetylated, cyanoethylated and styrene grafted cotton fabrics could be well transfer printed with disperse dye similarly to acetate and polyester fabrics. Light fastness was excellent, but durability to laundering was generally insufficient except acetylated cotton. As to cationic dyes, the printability was good for acrylic acid grafted cotton, fair for cyanoethylated cotton, but poor for carboxymethylated and acrylonitrile grafted cotton fabrics. Light fastness was generally good, but the fastness to laundering was almost poor.

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In order to obtain the polypeptide membrane having high permeability ratio of oxygen to carbon dioxide gas, the effect of chemical structure of the side chain on permeation and sorption behaviors was studied. Poly (L-methione) (PLM) was selected as the reference material, and its oxidation by hydrogen peroxide aqueous solution was made. The oxidized membranes obtained under severe oxidation condition and under rather mild condition are named as PLMO-I and PLMO-II, respectively. Each membrane has -SO- group in the side chain. Though the PLM and PLMO-II membranes have α-helical structure throughout the membrane, PLMO-I in the surface layer of the membrane may have somewhat disordered helical structure. The ratios of the permeability of oxygen to that of carbon dioxide gas are 0.37 for PLM, 0.53 for PLMO-II and 1.7 for PLMO-I. All of these values are higher than those, 0.1_??_0.2, of usual polymers. The high ratio for PLMO-I is due to the high affinity of oxygen for polymer and low diffusibility of carbon dioxide gas in the partially random coiled structure of the membrane surface layer.

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