The construction of a versatile viscometer of coaxial cylinder type is described. The apparatus can be used (i) not only as a viscometer by hanging a weight on a pulley attached to the inner cylinder and observing its rotation velocity or by rotating the outer cylinder uniformly and measuring the torque exerted on the inner cylinder, (ii) but also as a viscoelastometer by setting the outer cylinder in rotatory oscillation and recording optically the oscillatory motion of the inner cylinder, thus enabling us to evaluate the amplitude ratio and phase difference between these two motions and therefrom the dynamic viscosity and rigidity of a specimen in a frequency range up to 10 cps. Some results of preliminary measurements on silicone oils are presented as examples.

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Two experiments are made concerning the rotational viscometer of coaxial cylinder type reported in the preceeding paper.(i) The end correction of the apparatus is investigated and its magnitude is estimated as several % under usual conditions by taking the value of viscosity by the falling ball method as a standard. In analyzing the experimental results, the rigorous solution for the problem worked out by S. Oka is referred to.(ii) The temperature rise due to continuous rotation of the viscometer is followed at a point in a silicone liquid specimen of 10, 000 cS grade, and is found, 30 min after the start of the rotation, to be several degrees of Centigrade at an angular velocity of 34 sec^-1. Accordingly at such a rotation velocity the measurements have to be completed in much shorter time in order to determine correctly the (shear rate dependence of) viscosity.

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The Number average molecular weight of unfractionated low conversion polyvinyl acetate was determined by osmotic measurement in benzene solution. Zimm-Meyerson type osmometer was used. The number average values obtained were found to be about half of the weight average ones by light scattering method as was expected from theory. The viscosity molecular weight relationship approximately agrees with reduced Wagner's and Chinai's relations.

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The weight average molecular weight of unfractionated low conversion polyvinyl acetate was measured by light scattering method. The values obtained in acetone, methyl ethyl ketone and methanol agreed approximately. Zimm plot, K_c/Rθ against sin² (θ/2) is linear as excepted in the case of M_W/M_N=2, which corresponds to the molecular weight distribution of low conversion polyvinyl acetate. In acetone solution the relation between molecular dimension and molecular weight found to be ‹D²›W∝MW^0.57. The Flory's constant Φ in acetone solution is (2.2+0.2)/10²³.

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The process of polymerization of silicone-tetramer by concentrated sulfuric acid can be divided in two steps, the one is the formation of sulfated siloxane polymer which is in equilibrium with sulfuric acid and the other is the final polymerization with large quantity of water. The molecular weight of siloxane polymer at the first step has been measured as the alkoxy ether of polymer (Fragment polymer) stabilized with anhydrous ethanol, and compared with the molecular weight of final polymer stabilized with water as a function of quantity of sulfuric acid. The observed molecular weight of “Fragment polymer” at relatively small quantity of sulfuric acid are close to the calculated molecular weight based on equilibrium mixture of mono- or di-sulfate ester of siloxane polymer. The observed molecular weight of “Fragment polymer”at large quantity of sulfuric acid does not increase parallel with the molecular weight of final polymer, and it was suggested that excess sulfuric acid mainly affect the final polymerization-process.

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Molecular weights of siloxane polymer stabilized with anhydrous ethanol and with water have been measured as a function of concentration of sulfuric acid. The dependence of both kinds of the molecular weights are parallel and those ups and downs coincide with the electrical resistance curve of sulfuric acid. It is presumed that more ionized sulfuric acid could split siloxane polymer into smaller molecules at the first step of polymerization.

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The copolymerization of vinyl chloride (VC) and crotonic acid derivatives was studied at 50°C in emulsion system, with potassium persulfate-sodium sulfite used as initiator. Derivatives are crotonic acid (I), ethyl crotonate (II), vinyl crotonate (III) and allyl crotonate. MRR is r₁=2.4, r₂=0 in (I), r₁=2.0, r₂= 0 in (II) and r₁= 0.98, r₂=0.97 in (III), respectively, Crotonyl group copolymerizes with VC to the same degree as vinyl acetate does with VC. Copolymers of VC-I and VC-II are soluble to aceton-methanol mixed solvent. There component copolymerization of vinyl chloride-vinyl crotonate differs from vinyl chloride-vinyl acetate-crotonic acid system, and the former is restricted in the copolymerization prosses. The k′ of Huggins at the gel point by cross-linking is 0.53, and the chain transfer constant of crotonic acid is 2.1×10^-3.

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Using crotonyl peroxide (CPO) as initiator, bulk polymerization at 50°C was studied. The catalytic action is more excellent than lauroyl peroxide. Apparrent activation energy of polymerization is 20.4 kcal/mol, which is small for peroxide. If the CPO concentration is above 1/400 eq. mol per monomer, insoluble polymer is obtained, and if the CPO concentration is below it, polymer obtained is soluble in a solvent. The k′ of Huggins is 0.4-1.8, which is larger than ordinary polymer, 0.3-0.4. It is obvious, therefore, that the branching part of polymer is large. The k′ of Huggins at the gel point by branching was 1.82. Compared with the k′ of the gel point by cross-linking is 0.5, it is interesting. The rate of polymerization is proportional to [I]^0.50.

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Two synthetic procedures of dimethylol urea dialkyl ethers in non-aqueous medium by strong alkali catalyzed method were compared. One of them starts from alcohol, paraformaldehyde and urea by one step process. Another one starts from alcohol and dimethylol urea which was prepared beforehand. It was confirmed that higher purity ether could be obtained by the latter method than the former. According to the investigation by infrared spectroscopy, these ethers are associated by the following intermolecular hydrogen bond “>NH…O=C<”compared with inter - and also intramolecular hydrogen bond, “>OH…O=C<”and “O -H-…O=C<”, in the case of dimethylol urea molecules.

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In the previous reports, it was considered from the absorption isothermal curve with Azo Geranine 2G as the absorbent that the remarkable elevation of dyeing property of steam-set nylon 6 fibre may not possibly caused by the hydrolysis. Then, in the present paper, the measurements of relative viscosity, amino and carboxyl terminal groups were carried out on drawn and undrawn fibres which had been treated by dry and steam-setting under tension or no tension. From these results, the previous conclusion was confirmed.

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Copolymerization of Acrylamide (M₁) with acrylic acid (M₂) initiated by K₂S₂O₈ was carried out in water at 50±1°C. When the degree of dissociation of acrylic acid was about 0.5, the ratio of M₁ to M₂ in copolymer was maximum. Monomer reactivity ratios of monomers changed with pH as tabulated in Tab. 5. The influence of pH on the rate of polymerization of acrylamide was investigated. It was observed that the rates were nearly constant in the range of pH of 3.3-8, but went down at pH>9.

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The phenolic hydroxyl groups in the skelton of cross-linked resins are sulfoethylated with sodium β-bromoethane sulfonate (I). NaR type resorcinol-formaldehyde resin (II) was used as a model, which was prepared by azeotropic suspension polycondensation (cf. C.A. 50, 507h). II was heated in a saturated solution of I. The amount of introduced sulfoethyl group into II was 1.1 meq/g. Sulfonated phenol-formaldehyde resin prepared by the azeotropic polycondensation is also treated as the above. The increase of salt-spritting capacity was 9.5% and the total salt-spritting capacity showed 3.46 meci/g.

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