It is suggested that the chain polarity of native cellulose, cellulose I, is preserved in the course of the transformation to cellulose II by mercerization as a resonable interpretation of following results. The selective uniplanar orientation of (1_??_0) plane of original bacterial cellulose is maintained during and after mercerization to provide cellulose 11 pattern resulted in the preferential orientation. Furthermore, when the air-dried or never-dried spherulite of bacterial cellulose was immersed in 18% NaOH, the Maltese cross pattern and the color correlation are the same as those of the original. There are several other evidences for the same polarity of cellulose 1 and II. It was proved that cellulose triacetate (CTA) I can be formed by the heterogeneous acetylation of cellulose II as well as cellulose I when the swelling in the pretreatment media is low. It seems that parallel arrangement is not necessarily correct structure of CTA I. It is possible to transform CTA I to CTA II without any dissolving process but by a comparatively simple treatment with superheated steam. These mean that CTA I and CTA II have the same polarity in their crystal structures. The transformation of cellulose I to cellulose II through cellulose III_I which is hydrolyzed by 20N H₂SO₄ without disolution has been newly observed in the present study. Completely amorphous wood pulp decrystallized by the mechanical milling is recrystallized to cellulose II with water or 1% NaOH. It seems to be difficult to reverse the chain or to attain antiparallel arrangement from parallel one during the mechanical milling. On the other hand, the chain polarity problem has been solved by the direct TEM observation of LODP cellulose reacted with hydrazine. Characteristic microfibril of the LODP cellulose are observed with uniform width and length of about 200A and 2000A, respectively. In contrast with this, the reacted microfibril is long but has irregular pattern in shape. The possibility of antiparallel arrangement in ramie cellulose has been directly proved by the microphotographs.

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The kinetic and equilibrium measurements of water vapor sorption were carried out on the four kinds of chitosan membranes. The sorption isotherms were all sigmoidal, though one of the membranes showed a sigmoidal one which was accounted for by the solution mechanism in the high pressure range. The amount of sorption depended on the preparation method of the membranes. The diffusion coefficient at a given vapor pressure widely varied from one to another, From these results, the cohesive state of molecular chains in the amorphous region was discussed.

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In the previous reports^{1, 2)}, the difference between the respective compressibilities of a twistless yarn fabric and a conventional twisted yarn fabric was reported. It is made clear that, whereas the compressibility of the conventional twisted yarn fabric is little influenced by the fabric density, that of the twistless yarn fabric is much influenced by the fabric density. The present report has it as an object to make more definitely the effect of the twist of the yarn on the compressibility of the fabric. Five kinds of yarns different in the twist constant were spun and fabrics were woven of the respective yarns. The followings are made clear from the compressive force-strain curves of the respective fabrics and analyses of the deforming behaviors of the yarns in the fabrics. The compressive force-strain curve of the fabric is represented by the following equation: where P is a compressive force in g/cm², 1-h/h_0.5 is a strain, B is a constant of 0.5g/cm², and β is a compression characteristic value.
Here, the factor β is called a compression characteristic value showing the degree of the compressibility of the fabric. That is to say, the fabric low in the value of β means a fabric easy to be compressed and high in the softness. This β is very much correlated with the yarn packing factor (1-ε0) in the initial fabric. (1-ε0) can be represented also as a function of the yarn twist constant (T) and fabric density (N_c.p ). From these relations, the compression characteristic value β and compressive force-strain curve can be determined by calculation and further coincidence of the calculated value and experimental value is recognized. In the stage of weaving and designing the fabric, β can be calculated and the softness of the fabric can be known in advance.

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The cationic ring-opening polymerization of 1, 4-anhydro-2, 3-O-cyclohexylidene-α-D-ribopyranose (ACRP) gave stereoregular polysaccharide derivatives, that is, 2, 3-O-cyclohexylidene-(1→4)-β-D-ribopyranan with antimony pentachloride as catalyst in methylene chloride at low temperature. ACRP is the third 1, 4-anhydro sugar that can give the cellulose-type polysaccharide derivative. In addition, copolymerization of 1, 4-anhydro-2, 3-O-cyclohexylidene-α-D-ribopyranose with 1, 4-anhydro-2, 3-O-benzylidene-α-D-ribopyranose (ABRP) was attempted using antimony pentachloride as catalyst, revealing that (1→4)-β-linked stereoregular polysaccharide derivatives were obtained. Analysis of the structure of polymers was performed by ¹³C and ¹H NMR spectroscopy and optical rotation.

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Photo-induced graft copolymerization of methyl methacrylate onto carboxymethyl cellulose (CMC)-metal salts has been studied.
The degree of grafting and the apparent number of grafted chains of CMC-Na salts increased with increasing carboxyl contents, CMC and monomer concentrations. Without the CMC, no polymerization occurred. The branched chain length and the apparent number of grafted chains were able to be controlled to some extent by adding organic solvents and additives to the polymerization system.
The degrees of grafting of CMC-Me salts (7 species) were greater than those of CMC-Na salts and not affected by the species of metal ions but the ion exchange capacities.
In all cases, it is inferred that the photo-graft copolymerization onto CMC-Me salts is initiated by the photolysis of carboxyl groups and terminated by the reaction between growing polymer radicals and cellulose radicals.

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The equilibrium absorption method by serial samples of different length was adopted for a reliable technique to determine the internal volume/radius distribution of fabrics and the calculation procedure was improved. Experimental results on 12 varieties of commercial fabrics were reported and applicability of the improved procedure to analysis was discussed.
On the basis of the comparison of V_pl/T, the ratio of total estimated volume to the thickness, with the porosity value obtained with specific gravity method, it can be concluded that the improved procedure affords proper estimation of internal volume in major sample fabrics.

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Bending rigidities of lock-stitch seamed fabrics were found out for two layers fabrics with the seam running perpendicular to the axis of bending. The results were developed for stitch density and sewing thread crimps in the seams. Relation between the bending rigidities and the sewing thread crimps was discussed.

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