Hardwood dissolving sulphate pulp was chlorinated with methanesulphonyl chloride /and thionyl chloride in N, N-dimethylformamide under the heterogeneous conditions. The following results were obtained:
(1) Chlorination with methanesulphonyl chloride occurred only at C₆ of a glucose residue to a small extent.
(2) Chlorination with thionyl chloride occurred at the secondary carbon atom, in addition to the chlorination at C₆, to yield 3, 6-dichloro-3, 6-dideoxy-D-allose residue and a trace of 4, 6-dichloro-4, 6-dideoxy-D-galactose residue.
(3) Reaction of cellulose with thionyl chloride generated a lot of sulphur as a by-product and caused severe depolymerization. The calculated values of chlorine content were lower than theoretical ones expected from gas-liquid chromatographic analysis because of sulphur contaminant.

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Rayon fibers were metallated with Li, Na and K methoxides in pure methanol or a mixed solvent consisting of CH₃OH and dimethyl sulfoxide (DMSO) (1:1v/v) and the metallated fibers were allowed to react with acrylamide (AAm) in various solvents by the anionic mechanism to give graft copolymer with poly-β-alanine branches as well as polyacrylamide branches.
Effects of a swelling pretreatment in water or DMSO, Na metallation time and medium, and methoxide concentration upon the degree of the metallation were investigated. The degree of Na metallation increased with CH₃ONa concentration for the water- or DMSO-swollen rayon and the degree of metallation was higher for the latter. The higher degree of Na metallation was obtained on the exchange reaction with CH₃ONa in the mixed solvent (1:1 CH₃OH•DMSO) than in pure methanol at lower concentration of CH₃ONa, and the degree of Na metallation of the DMSO-swollen rayon increased with the DMSO content in the mixed solvent.
Effects of the AAm concentration, degree of metallation and reaction temperature upon the total graft-on and the graft-on via transition polymerization were investigated in various solvents. The total graft-on increased with the AAm concentration in the reaction solution for the Na metallated rayon. The graft-on via transition polymerization which was determined by the analysis of prim. amide nitrogen increased with the AAm concentration and was 8_??_34% of total graft-on. The graft-on was scarcely influenced by the addition of an inhibitor of radical polymerization into the reaction solution. Apparent activation energies of the graft-polymerization were 8_??_11kcal/mol for the Na metallated rayon fibers treated in various solvents. Both curves of the total graft-on and the graft-on via transition polymerization vs. the degree of metallation with Li, Na and K had maxima at 0.22_??_0.32mol/AGU (AGU: glucose unit) and their maximum values increased with an increase in the degree of swelling of the preswollen rayon, with a decrease in the dielectric constant of the solvent in the reaction solution and with an increase in the electropositivity of the alkali metal used.

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Cotton fabrics were treated with poly(acryhc acid), (PAA), in the presence of ammonium chloride by the conventional pad-dry-cure technique and the effects of this treatment were investigated.
The wrinkle recovery of the treated cotton fabrics improved with the resin add-on up to 1.1%: the maximum wrinkle recovery angle (F+W) of the treated fabrics was 196 deg. in the conditioned state and 222 deg. in the wet state at 1.1% add-on.
Over 1.1%, the angle decreased sharply and thereafter kept constant with increasing the resin add-on. The moisture regain decreased with increasing the resin add-on to reach the minimum moisture regain of 3.8% at 1.3% add-on. Further increase of the resin add-on kept the regain value constant.
The crosslink formation between cellulose molecules with PAA was considered, since PAA film did not give any insoluble product when heated in the presence of ammonium chloride.
The hydrolysis of the treated fabrics coupled with the IR measurements showed that the free acid content decreased gradually to a minimum at 1.4% of the add-on and then increased sharply, while the content of the reacted acid increased up to 2.0% resin add-on and leveled hereafter.
We suggest that the maximum wrinkle recovery is correlated with the minimum free acid content and therefore the cross-linking by the esterification between the acid and cellulosic OH is responsible to the improved properties of the fabrics

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Cotton cellulosic fibers were treated with aqueous solutions containing 7% acrylamide and 3% sodium hydroxide at 30°C, and 7% acrylamide and 20% sodium hydroxide at 20°C. The fibers were easily carbamoyl-ethylated and carboxyethylated in the presence of 20% sodium hydroxide as compared with the case of 3% sodium hydroxide. In both reaction systems, the total degree of substitution was increased as reaction time proceeded. _??_owever, in the reaction system containing 20% sodium hydroxide, number of carbamoylethyl groups was increased at the initial period of reaction, and decreased at the latter stage of reaction. On the contrary, number of carboxyethyl groups increased rapidly as that of carbamoylethyl groups was decreased. These phenomena are elucidated by hydrolysis of carbamoylethyl groups to carboxyethyl groups under alkaline conditions. Degree of crystallinity of the treated cellulose was measured with X-ray diffractometer under dry and wet conditions. The degree of crystallinity of cotton fibers treated in the presence of 3% sodium hydroxide was almost unchanged under dry and wet conditions as same as untreated fibers. However, the degree of crystallinity of cellulose treated in the reaction system containing 20% sodium hydroxide measured under wet conditions was less than that under dry conditions. It is thought to be caused from the fact that carbamoyl-ethylation and carboxyethylation occurred not only in the amorphous regions, but also in crystalline regions in the reaction system containing 20% sodium hydroxide, and in the case of 3% sodium hydroxide solution the substitution reaction did not occur in crystalline regions. Moisture regain of the treated fibers was not changed mostly by carbamoylethylation and carboxyethylation. However, water imbibition increased remarkably by treatment in the reaction system containing 20% sodium hydroxide. Grafting reaction of ethylacrylate to the fibers treated in the reaction system containing 20% sodium hydroxide for 10 hr was also carried out. The X-ray diffractgram of the grafted sample was flat even measured under dry conditions. It was found that stable decrystallization of cotton fibers was achieved by graft copolymerization onto the fibers carbamoyl-ethylated and carboxyethylated in the presence of 20% sodium hydroxide. Such results are considered to be due to carbamoylethylation and carboxyethylation, and subsequent graft copolymerization occurred in the crystal regions of fibers. From the results mentioned above, it is assumed that crystalline region of fibers treated with acrylamide in the presence of 20% sodium hydroxide is stiff and stable under dry conditions, but very unstable under wet conditions, and stable decrystallization was achieved by graft copolymerization in the treated fibers in 20% sodium hydroxide solution.

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Cotton, rayon and polynosic fibers were treated with formaldehyde under the wet conditions. The apparent dry density of the crosslinked fibers decreased linearly with increasing amount of combined formaldehyde, for each cellulose species. The apparent dry density of the crosslinked rayon and polynosic fibers decreased more markedly than that of the crosslinked cotton fibers. Swelling of the crosslinked fibers in aq. NaOH was studied. The degree of swelling of the crosslinked fibers increased with increasing amount of combined formaldehyde in water and dilute aq. NaOH while it decreased in conc. aq. NaOH. The critical concentrations of aq. NaOH at which the swelling tendency in relation to the amount of combined formaldehyde was reversed were 10-12.5%, 3-5%, and 6-7.5% for cotton, rayon and polynosic fibers, respectively. The swelling behavior is explained by the double network structure of cellulose made up by crystalline and hydrogen-bond networks in the amorphous region, and by the destruction of the crystalline network at the critical concentration of aq. NaOH.

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Reverse osmosis of aqueous solutions of urea and its N-substituted derivatives was studied using cellulose acetate and modified cellulose acetate thin membranes.
The membrane performance of cellulose acetate was improved by grafting with butyl acrylate or blending with poly(i-propyl glutamate).
The partition of solutes was found to be an important factor of solute separation. It was also found that the structural change of water in the membrane as compared with the state in solution affects the permeation properties. These facts accord with the solution-diffusion mechanism.

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The diffusion coefficients of disperse dye in cellulose triacetate in organic solvent dyeing were determined by the film-roll method, and following results were obtained.
(1) The temperature dependence of the diffusion coefficients of C. I. Disperse Red 17 in organic solvents obeyed the Williams-Landel-Ferry equation, where a_T is a shift factor and T_s the standard temperature.
(2) The standard temperature was correlated with the solvents. The effect of solvents on the diffusion coefficient was explained in terms of the lowering of T_s due to the lowering of the glass transition temperature of cellulose triacetate with the absorbed solvent.

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The purpose of this paper is to investigate the effects of solvents on the diffusion coefficient of C. I. Disperse Red 17 in diacetate from a viewpoint of the Williams-Landel-Ferry equation. The diffusion coefficient was determined by the film-roll method, and following results were obtained:
(1) The relation between the diffusion coefficient and temperature in organic solvent dyeing are expressed by the Williams-Landel-Ferry equation, where a_T is a shift factor, and T_s the standard temperature.
(2) The diffusion coefficients are correlated with T_s of diacetate, and increase with decreasing T_s of diacetate.

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Properties of cotton fabrics carboxymethylated by the following methods were examined:
(1) Cotton fabrics were immersed in sodium hydroxide aqueous solution at 60°C after immersion in aqueous solution of monochloroacetic acid or sodium monochloroacetate and squeezing (conventional two baths method).
(2) Cotton fabrics were heated in the mixed aqueous solution of sodium monochloroacetate and sodium hydroxide or in air at 60°C after immersion at 10°C in the mixed aqueous solution of the same composition as above (one bath method).
(3) Cotton fabrics were heated in air at 140°C after padding with mixed aqueous solution of sodium monochloroacetate and sodium hydroxide (pad-bake method). Partially carboxymethylated cotton fabrics having the degree of etherification of about 5-6 mole% were prepared by these methods, and various properties examined, such as moisture regain, tensile strength and elongation, property for soiling and washing, dyeing property, colorfastness, and discoloration by perspiration.
These carboxymethylated cotton fabrics had generally higher moisture regain, soil removal, dyeability for basic and cationic dyes than untreated or mercerized cotton fabric. But in the case of cationic dyes fairly large difference was found in dyeability and colorfastness according to the kind of dyes. Sample fabrics prepared by the one bath method showed higher moisture regain and dyeability for basic dye. Sample fabrics prepared by the pad-bake method had considerably low moisture regain, tensile strength, elongation and dyeability for direct and reactive dyes.

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