The life-time of cellulose is predicted by using the Ozawa-Wall-Flynn method. Mass decrease of cellulose powder and cotton fabric was investigated by thermogravimetry at various heating rates in air and nitrogen flowing atmosphere. The relationship between life-time of cotton, holding temperature and mass decrease are obtained. The life-time of 10 % mass decrease varied from several hundred years to several seconds in a temperature ranging from room temperature to 573 K. The effect of atmosphere was apparent in a high temperature range

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Egyptian maize starch was used as starting material for preparation of starch derivatives via hypochlorite oxidation or etherification. The latter comprises cyanoethylation carbamoylethylation and carboxymethylation. The native and modified starches were evaluated as thickening agents in discharge printing of polyester/cotton-blended fabrics. The printed fabrics were previously dyed with dischargeable reactive and disperse dye mixture, using white or coloured discharge printing styles. After printing and steaming at different temperatures, for different intervals of time, the printed samples were washed, dried and assessed for degree of whiteness and colour strength (K/S). It has been found that the degree of whiteness and colour strength (K/S) depend on the time and temperature of steaming as well as the nature of thickening agent used. The highest degree of whiteness and the highest (K/S) were obtained for the samples printed with pastes thickened with carbamoylethyl starch and steamed for 8 minutes at 200°C. The overall fastness properties, e.g. rubbing or washing for the coloured printed goods ranged between 4 and 5 with the exception of the samples printed with native or hypochlorite oxidized starch pastes, which acquired a harsh handle.

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Some microorganisms, which hydrolyze ester bond of diethyl p-phthalate were isolated from wastewater and soil samples obtained from several locations by cultivation using an enrichment culture medium containing diethyl p-phthalate as sole carbon source. As degradation product of diethyl p-phthalate, terephthalic acid was determined in the culture broth. When aerobically grown in a medium containing 0.5% of diethyl p-phthalate and minerals at pH 7.0 and 30°C, the isolated microorganisms degraded from 41.6-54.4% diethyl p-phthalate for 14 days. The test pieces of electron beam rayed polyethylene terephthalate (PET) fiber in the medium were also incubated with isolated microorganism at 30°Cfor 14 days. The incubated PET fibers were observed by scanning electron microscopy. The cracks were found on the surface of PET.

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To investigate the penetration of polyethylenimine (PEI) into human hair, cross-sectional samples of white human hair treated with PEI were prepared. In particular, a novel method to analyze the diffusion behavior of PEI in human hair was developed, in which the PEI parts in the cross-sectional samples were dyed with orange II and the cross sections were examined at a wavelength of 487nm (λ_max of orange II) with a microspectrophotometer. In our method, the penetration of PEI into bleached human hair clearly increased with increasing treatment time, and with decreasing molecular weight. In addition, the diffusion pattern of PEI at pH11.1 displayed Fickian type characteristics. This suggests that the diffusion coefficient of PEI is essentially independent of PEI concentration. By calculating the diffusion coefficient from the PEI concentration profile, the diffusion coefficient of PEI (Mw: 300-600) was found to be the order of 10^-10 cm² /s.

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A new kind of size latex was developed for the sizing of wool yarn by graft copolymerization of two acrylic monomers onto gelatin. The product was analyzed by FTIR and the grafting copolymerization was confirmed. 10% water solution of the size showed low viscosity and good heat stability with excellent penetration properties in the wool yarn. By sizing treatment, strength of the yarn was greatly improved and the elongation at low stress was reduced. The size showed good desizing properties and the size film can be dissolved in boiling water easily.

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The bulk crystallization behavior of poly(3-hydroxybutyrate-co-4-hydroxybutyrate) [P(3HB-co-4HB)] were studied using polarized light microscopy, differential scanning calorimetry, and wide- and small-angle X-ray diffraction. Under the isothermal crystallization condition, the linear growth rates of the P(3HB-co-4HB) spherulites were measured at various temperatures and the influence of mutual disturbance for both comonomer components was clarified. The long period of P(3HB-co-4HB) increased much less with an increase in the crystallization temperature, compared to that of P(3HB). These results imply that the P(3HB) crystal excluded the 4HB component when, for example, the content of 4HB component in the copolymer was 5 mol%.

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