The initial resistance of fabric to extension in warp or weft direction is theoretically studied by applying the same theory of extension used for crimped yarn axis, the form of which has been explained in the previous papers by the authors. Load (P) at extension (Δ/l₁) is explained by the following equation.
where, P: Load induced by extension (Δ/l₁)
(Δ/l₁): Extension
a, l, n, m, : Parameter of yarn axis curve (m₁′=m₁+1)
(EI): Bending rigidity of yarn
p₁: Crimp ratio of yarn extended
sufix 1……for extended yarn.
sufix 2……for transvers yarn to extended yarn.
These results are applied to three types of fabrics constructed equally and with yarns having different bending modulus. It is explicit that the above equation may be applied to the load-extension curves of fabric.

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The relation between the lateral-order distribution in the 6 nylon fibres and its specific volume is discussed.
The relation is explained sufficiently on the assumption that the larger the ΔF_u^i* value of the cohesive state is, the smaller the value of the specific volume.

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Vinyl acetate (VAc) was polymerized at temperature ranging from -30°C to +60°C in the presence of catalysts prepared from tri-n-butyl boron (BBu₃) and a, a′-azo-bisisobutylonitrile (AIBN).
In addition, polymerization of VAc was carried out at 30°C using BBu₃ as catalyst in methanol (MeOH) and in methylacetate (MeOAc), and also carried out at 60°C in MeOH using three kinds of catalysts, (1) AIBN, (2) BBu₃ and (3) AIBN-BBu₃ mixtures.
These polyvinyl acetates thus obtained were saponified to polyvinyl alcohol (PVA) and further deesterified.
From the viewpoint of crystallinity and stereoregularity, the PVA prepared at the lower polymerization temperature has better qualities and the PVA (A) derived from polymerization in MeOH has much higher crystallinity and regularity than the PVA (B) derived from polymerization in MeOAc.
Heat treated and not formalized PVA fibers derived from PVAc polymerized temperature below 10°C, neither dissolves nor shrinks in hot water up to 115°C. These fibers have very good resitance to hot water but their properties, such as tenacity, elongation and elastic recovery are not influenced by the polymerization temperature.
Heat treated fibers prepared from PVA (A) have much better resistance to hot water at 110°C than those prepared from PVA (B), but other properties do not differ between (A) and (B).
The properties of PVA and the fibers obtained from it are not influenced by the kinds of catalysts, when the polymerization temperature is same.

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Rayon reduces in its gloss when acetylated in acetic anhydride-kerosene mixture with potassium acetate catalyst and washed with water. This phenomenon was studied in detail with cellophane. It is very difficult to measure the gloss of staple fibers, while the measurement of opacity for a given film is not only easy but reliable.
Cellophane, treated in the same procedure as written above, also reduces in clearness, looking opaque. In general, opacity of films is shown by 'Degree of Haze [H]'.
It was found that increase in [H] does not come from acetylation itself but from swelling of the acetylated cellophane in the acetylating liquid as well as deswelling of the swollen acetylated cellophane brought about by washing with water. When the acetylated cellophane swollen with hydrophobic acetic anhydride is steeped in water, acetic anhydride in the film as swelling agent forms lots of small particles in the film. These particles are gradually substituted by water, leaving their own traces in the film. Observation of the cross section of the opaque acetylated cellophane through a phase-contrast microscope shows a lot of small voids, which are thought to be the traces of particles mentioned above and scatter light beam. The higher the degree of acetylation of cellophane is, the higher [H] becomes.
Treatment with hydrophilic swelling agents, such as acetic acid and acetone, followed by washing with water, improves [H] of the acetylated cellophane to a great extent.
Cellophane, acetylated in acetic anhydride vapor, swells a little during its acetylating process with the result that this acetylated cellophane has a low [H], as compared with the former.
Alon, acetylated in acetic anhydride vapor, looks dull as if it contained TiO₂. High tenacity rayon, starting rayon of Alon, contains many small voids. These voids increase in number and size, when the rayon passes through the acetylating process. Treatment of Alon with acetic acid also gives rise to bright Alon.

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Carboxymethyl cellulose as ion-exchange adsorbent in biochemical fields has been prepared under several conditions using linter cellulose powder, adding calculated caustic soda solution. Such properties as Ovalbumin Adsorption, Amount of Carboxylic Groups and Elution Resistance have been tested.
It is found that Ovalbumin Adsorption and Elution Resistance are dependent on the amount of alkali solution present and its concentration at the reaction besides the degree of substitution.
It is infered that these differences of the properties result from the differences of the swelling magnitude which come from the differences of the distributions of carboxylic groups of the cellulose. When alkali concentrations are low and its amounts scarce, the distributions of carboxylic groups are less uniform.

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Using cerium salt as an initiator, the graft copolymerization of acrylamide on linter pulp cellulose was studied.
The quantity of the polymer grafted in the air is found to be smaller than that in nitrogen, but the difference in the reaction mechanism was hardly recognized in both conditions. Considering the elementary reactions from the experimental results obtained, the following mechanism of the graft copolymerization is surmised:
where Cell, Ce^iv and M are cellulose, tetra valent cerium and monomeric acrylamide respectively.

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