Possibility that the state of solution of viscose may be estimated from the symbols in viscosity formula was investigated. The viscoses were prepared by the emulsion xanthation methode. Concentration of cellulose is 2%. The results are as follows:
(1) Št. Kalafut evaluted a quality of viscose through a symbol “N” in Baker's equation, η_??_=(1+C [η]/N)^N. However it was found that for this purpose Martin's equation, log (η_sp/C)=log [η]+k [η] C is more appropriate for its simplicity in treatment for the results obtained.
(2) The symbols [η] and “k” in Martin's equation were used as parameters relating to the state of viscose solution. As was expected, [η] is proportional to the size of solute particles. On the other hand “k” is affected mainly by the interaction between the solute and the solvent. So it seems that for the evaluation of the state of viscose solution “k” is more suitable than [η].
(3) The viscose containing 14% of sodium hydroxide was diluted just before the viscosity measurement. The value k of each viscose decreases as the concentration of sodium hydroxide decreases. On the other hand, “k” of viscoses prepared from lower concentration of sodium hydroxide solution increases with decreasing concentration of sodium hydroxide.
(4) Within the range of experiments it may be said that the difference of the states of viscose solutions is recognized by a parameter k. The fact found by Št. Kalafut that the viscose giving small value in N (=k) has a good quality is ascertained.

View full abstract

Instability of the nature of viscose makes viscose study difficult. Diethylacetamide cellulose xanthate (DA-xanthate) obtained from viscose is stable, and it had been used for determination of γ value of viscose. Schurz noticed that the nature of DA-xanthate is similar to that of the original viscose. So he studied fluidity of dimethylsulfoxide solution of DA-xanthate, and found that the properties of solution represented not only the average molecular weight of cellulose, but also the state of original viscose solution. The purpose of the present paper is to examine the possibility of application of DA-xanthate for a viscometric study of viscose. So the symbols “[η]” and “k” in the Martin's eqation, log (η_sp/C)=log [η]+k [η] C are used as parameters relating to the state of solution as in the preceeding paper. The variations of these parameters of DA-xant-hate are compared with those of viscose. The results obtained are as follows:
The ripened viscose differs from the unripened viscose in γ value and the state of solution. Marked differences in γ value and the state of solution could be also found between DA-xanthates prepared from the ripened and unripened viscoses respectively. However a trend of variation in “k” of DA-xanthate differs from that of viscose. Consequently the conclusion drawn by Schurz that the state of dimeth ylsulfoxide solution of DA-xanthate representes that of original viscose could not be approved within the range of the experiments.

View full abstract

Considering the process of formation of vinyl polymer among the cellulose chain molecules in swollen state, the decrystallization of cellulose in the process of the hindrance to reformation of secondary structure in amorphous region by deposited vinyl polymer during drying is expected.
The graft copolymer was prepared by reacting methyl acrylate with viscose rayon using ceric salt as catalyst in aqueous solution, and the change in fine structure of the product was mensured by various physical methods.
Following experimental results were obtained:
(1) Contribution of methyl acrylate polymer grafted to the tensile stress of grafted collulose is negligibly small.
(2) Crystallinity of cellulose is not changed by grafting.
(3) Dry modulus of grafted yarn decreases but wet modulus does not decrease noticeably by grafting.
(4) Second transition temperature of grafted cellulose decreases with increase of the polymer grafted.
(5) Coagulation order of cellulose is distributed to low oredr side by grafting.
From these experimental results following conclusions are obtained;
(1) Methyl acrylate polymer is formed in the amorphous cellulose chain molecules.
(2) This polymer does not change the crystallinity of cellulose.
(3) This polymer binders the amorphous cellulose chain molecules from ordered coagulation during the drying and fixes the molecules in loosely coagulated state.
From these points of view, it may be said that the grafting onto cellulose leads to the destruction of cellulose secondary structure in amorphous reglon or the fixation of the cellulose in the “pseudo swollen state”.

View full abstract

1. Grafting of acrylonitrile (AN)-styrene (St) onto cellulose.
Just AN was grafted onto cellulose by ceric salt and after some minutes St was added.
Having the AN-St grafted cellulose obtained, it is effected that St would be grafted at the end of the grafted AN chain. The results obtained are;
(a) Degree of grafting of St in AN-St grafted product is at the maximum when AN reaction before the addition of St is 15 min
(b) Degree of grafting of St is also at the maximum with varied quantity of AN, and increases linearly with the increased St quantity.
(c) Formation of benzene-D. M. F. extract (homopolymer) would be due to the thermal polymerization by ceric salt.
2. Hydrolysis of grafted cellulose.
AN grafted and AN-St grafted cellulose were hydrolyzed by 2.5 N HCI sol. at such a mild condition as not to hydrolyze AN chains and to hydrolyze 10% of the original cellulose.
After the hydrolysis, 40% of the grafted chains was extracted. It means that 40% of the grafting occured onto such a part of cellulose that is accessible to hydrolysis.

View full abstract

In order to find out what contribution can be ascribed to α-CH…X thpe hydrogen bonding in disperse dyeing, R_f values of disperse dyes in paper chromatography are discussed from the view point of their changes when esters (or similar compounds) are added, and noted with the results as follows.
1) There exists the correlation between R_f value and ester concentration [A], where R_f0; R_f when [A]=0, K; equilibrium constant, and m; numbers of ester molecule combined with one dye molecule. Change of free energy (-ΔF) of interaction may be calculated from the estimated K value. (-ΔF=2.30 RT log K)
2) The smaller the electron density in α-CH position of ester is the larger -ΔF value becomes. hence it is concluded that α-CH group of group makes an important contribution to the interaction between disperse dyes and esters. This contribution is supposed to be the form of α-CH…X type hydrogen bonding.

View full abstract

1. The acid and alkali hydrolysis resistance of the cotton finished with dimethylolethylenethiourea (DMETU) was investigated and the results were compared with the cases of dimethylolethyleneurea (DMEU), dimethylolthiourea (DMTU), dimethylolurea (DMU) and formaldehyde finishes.
The order of durability to acid and alkali hydrolysis of these crosslinked fabrics is as follows; acid durability, alkali durability,
Therefore, DMETU finish has high durability to alkali hydrolysis and also considerable durability to acid.
From these results, it may be seen as a rule that DMTU or DMETU finish shown apparently higher acid hydrolysis resistance than DMU or DMEU finish. This is probably due to the reason why electron density on the amido nitrogen in the thioureas is smaller than in the ureas, since=S bond is more electron attractive than=O bond and accordingly resonance effect of the thioureas becomes more predominant than the ureas:
2. The strength loss by scorch test on bleached DMETU finished fabric is somewhat larger than that on DMEU finished fabric, but chlorine retention of the fabric is rather smaller than that of DMEU. This result does not perfectly support the inference proposed by D. D. Gagliardi. Yellowing by scorching, however, is a great defect of DMETU finish.

View full abstract