Viscose rayon was graft copolymerized by Co⁶⁰ γ-ray irradiation, being immersed in the aqueous solution of acrylonitrile.
The effects of various factors were examined, such as the time of irradiation, temperature, liquour ratio, denier of rayon, the monomer concentration and pH value of monomer solution. Also, using various kinds of rayon samples, the effect of the degree of swelling of fiber was examined and the percentage of grafting was found to be proportional to this property of fiber in solution system.
Microphotograph of the cross-section of grafted rayon (percentage of grafting 53.4y.) showed the uniform distribution of graft polyacrylonitrile. Also, graft polyacrylonitrile being isolated by acid hydrolysis method (cf part I), intrinsic viscosity was measured and found to be nearly equal to that of homo-polymer. Furthermore, the X-ray diffraction pattern of graft rayon was found to be composed of pattern of cellulose II and that of polyacrylonitrile. This fact suggests that graft polyacrylonitrile deposits in amorphous region and is crystallized.
The practical properties of grafted rayon were measured. The results showed that tensile strength, elongation and degree of crimping increase and tenacity decreases subject to the percentage of grafting.

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In view of the molecular structures of monomers, the reactivities of allylcellulose with vinylmonomers are discussed, and a structure of the reaction product between allylcellulose and methylmethacrylate (MMA) is infered from its thermal, mechanical and other properties.
Reactivities of allylcellulose with vinylmonomers such as styrene, P-vinyltoluene, methylmethacrylate, vinylacetate, ethylacrylate, acrylonitrile, α-methylstyrene and 4-vinylpyridine depended on the e values, electrodensities, but not clear of the Q values, degree of resonance, of these monomers. In other words the reactivities might increased with e. These observations seem th agree with higher electrodensity of an allylgroup owing to mesomeric effects of 0-atom toward allyl double bond.
A transparency of the reaction product of allylcellulose and MMA indicate the complete compatibility between them. The increase in ratio of the allylcellulose in reaction products brought less swellability and solubility in chloroform, lower elongation and higher softening and glass transition temperature. From a consideration of the above observation, it seems most reasonable to conclude that the reaction product has a network structure. Further from the linear relation between component ratio and glass transition temperature of the reaction product, it might be concluded that the reaction is very homogenous.

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It is a well known fact that a flow curve of polymer solution has a correlation to the molecular weight of the polymer. In this paper the flow curve is examined in anticipation that the flow curve of viscose has a correlation to not only the DP of cellulose, but also to the state of solution of viscose.
Four kinds of viscose which differ in the state of solution were prepared by varying DP of cellulose, distribution of DP, concentration of cellulose and r value. The flow curve was obtained by using a rotationary viscometer. To get a parameter which represents the characteristics of the flow curve, the flow curve was transformed into a straight line by plotting the viscosity (=1/fluidity) against shearing stress in a definite range. As parameters a slope of line “d” and an “intercept value” at shearing stress of 10⁴ dyne/cm² were chosen. These parameters were compared on the above mentioned viscoses.
The following results were obtained:
The parameter “d” increases with DP of cellulose and decreases with the concentration of cellulose in viscose. The γ value has no effect on the value of “d”. Ununiformity of the distribution of DP tends to make the value of “” larger. However the parameters are strongly dependent on the concentration and DP of cellulose. As there is little difference between the parameters before and after filtration of any viscose, a conclusion that the flow curve is of little value on evaluation of the state of solution of viscose within a range of this experiment can be drawn.

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Purified linter was oxidized with tert-butyl chromate in benzene with AcOH and Ac₂O, and both crystalline cellulose I and amorphous cellulose II were oxidized with this neutral oxidant in CCl₄. Acidic oxidation produced mainly carboxyl group to 150m moles, and 50m moles of aldehyde and 4-5m moles of ketone per 100g linter. This reaction was too drastic to investigate the oxidation of crystalline and amorphous cellulose at an early stage. In crystalline cellulose I, neutral oxidation produced 16m moles of aldehyde group, 7.5m moles of carboxyl and little ketone and it produced no change in crystal lattice and crystallinity obtained by means of X-ray diffraction, while in amorphous cellulose II, oxidation occurred even at 0°C, and 9m moles of ketone group which was not seen in cellulose I, 6m moles of aldehyde, and little carboxyl were produced, and besides appreciable degradation was observed from the figures of yield and X-ray diffraction. Alcohol group in C₂ and C₃ were oxidized to ketone, too.
In general, neutral tert-butyl chromate oxidizes cellulose heterogeneously; in crystal region oxidation of primary alcohol group to aldehyde in C₆, successively followed by the oxidation to carboxyl, mainly occurs, and in addition oxidation of secondary alcohol in C₂ and C₃ to ketone and considerable amounts of oxidative degradation of molecules in amorphous region occur. Acidic oxidation is so drastic that many oxidized groups are produced.

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In order to explain the relation between the mode of solubilization by non-ionic surface active agent and the chemical structure of the disperse dyes, visible light absorption spectra of the aqueous dispersions of several aminoanthraquinone dyes were measured for varied contents of the non-ionic surface active agent added as dispersing agent. In further experiment polyoxyethylene glycol, the chemical structure and the properties of which were just the same as those of the hydrophilic group of the non-ionic surface active agent, was used as dispersing agent in place of the latter, and absorption spectrum obtained for each dye was investigated for comparison as well as that of the n-hexan or the benzene solution of the same dye, respectively. The experimental results suggested the following:
(1) While 1, 4, 5, 8-tetraamino-, 1, 4-diamino-and 1-amino-4-hydroxy-anthraquinone were solubilized into the hydrophilic region of the micelle, 1-amino-2-methyl- and 1-methylamino-derivative get in the inner hydrophobic, when the content of the non-ionic dispersing agent is increased above CMC, and the micelle is formed in the solution.
(2) 1, 4-bismethylaminoanthraquinone, however, may be solubilized into the region between the hydrophilic and the hydrophobic of the micelle.

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Basic studies on a high temperature continuous bleaching of cotton sliver were made. Each 0.7g cotton sample was soaked in a 1-3% NaClO₂ solution and centrifuged to a liquor ratio 1:1, which was placed in a small titanic autoclave and heated at 110-160°C for several minutes. After cooling, the undecomposed NaClO₂ was titrated and the reflectance and DP of the bleached cotton were measured. The bleaching liquor was unbuffered and the pH decreased from 7 to 5. The results are:
(1) An apparent activation energy is obtained to 28.3kcal/mole for the NaClO₂ decomposition reaction both in the cases of 1% and 3% solutions from the initial rate of NaClO₂ decomposition; the degree of decomposition of NaClO₂, e. i., the amount of the decomposed NaClO₂ relative to the initial amount, of the 3% solution is larger than that of the 1% solution.
(2) The reflectance increases rapidly and levels off within 1 to 2min. at 140-160°C. An apparent activation energy of the bleaching reaction is 28.6kcal/mole and equal to the activation energy of the NaClO₂ decomposition. The reflectance of the bleached cotton increases to 85, the maximum value, from 66, the reflectance of the unbleached cotton. The reflectance retrogrades uuder too severe conditions.
(3) The reflectance at the expense of equal amount of NaClO₂ per g cotton is larger when 1% solution is used than when 3% solution is used.

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