A relation between change in electrical volume resistivity (R) and volume-shrinkage (ε)(ε=ΔV/V, where ΔV is volume contraction and V is initial volume) on crosslinking of amorphous polymers is derived by applying the theory of molecular and segmental mobility in glassforming substance above glass transition temperature proposed by Cohen, Turnbull, Okano and Hideshima. This derivation is based on the concept that the volume-shrinkage is only due to the reduction of free volume accompanied by crosslinking. The relation is where υf₀ is the average free volume per segment before crosslinking, υ* is critical volume just large enough to permit an ion to jump into it and R_o, γ and θ are constants. In addition, it is derived that the temperature dependence of electrical volume resistivity of amorphous polymers above glass transition temperature is expressed by an equation of the WLF form. Proportionality of the relation between l/ln (R/R₀) and 1/ε is experimentally confirmed on the polymerization process of unsaturated polyester resins and epoxy resins.

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A theory has been presented to account for the sorption of water vapor by powdered foodstuffs and the effect of moisture proofing by packaging films upon the rate of vapor transmission. It was found that the theory developed for powdered foodstuffs (single system) reasonably describes the experimental data obtained recently by Sone et al. A simple relation has been found for the sorption rate constants, K and K′, of single system and the film-powder composite systems. The values of K′, for several powdered foodstuffs and packaging film combinations were calculated from the data of sorption isotherm of powder and the permeability coefficient of films and compared with the experimental values. Both data were in good agreement.

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In general, as the rates of ion exchange and resin washing depend on the diameter of particles, it is considered that the rate of the change of particle diameter should be determined prior to the analysis of the performance of ion exchange column. Therefore, at first, the rate of the change of particle diameter was pursued microscopically at the certain intervals of time in the case of no ion exchange occur. The samples used were sulfonated 2-16% DVB crosslinked styrene resins in H+ form. In the first place, when a sample swollen in water was immersed in various acid or non-electrolyte solutions, it contracted suddenly and then became minimum in its diameter before attaining to equilibrium state.
On the contrary when the sample, contracted in acid or non-electrolyte solution, was immersed in water, generally it swelled suddenly and attained to equilibrium state after through the maximum of its diameter.
The similar results were obtained when the resins were immersed in solutions containing the same cations as counter ions. However, the shape of curves obtained in the strong electrolyte solutions differed from those in non electrolyte solutions.
In consideration of these processes, these contraction and swelling phenomena might be concerned with the mass transfer in a particle and the elasticity of resin.

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The contraction and swelling phenomena with ion exchange were observed. The samples were sulfonated 2-16% DVB crosslinked styrene resins which were the same ones as used in the previous paper. When a resin in H⁺ form swollen in water was immersed in various concentrate solutions with different cations and exchanged with them, it contracted suddenly and, after that, its contractivity increased in proportion to logarithm of time. Then, the slope of the curve decreased gradually and reached to the equilibrium state. The gradient of linear portion did not depend on the change of concentration but on the kind of cations. In the dilute solution, some part of the slope of the contractivity versus time was also linear and depended on both the kinds of cation and their concentrations.
Inversely, when resins having various counter ions were regenerated with acid solutions of various concentrations, their diameters rapidly became minimum and then swelled up slowly to the same equilibrium value as the resins in H⁺ form in acids. Effect of polyvalent counter ions on the contractivity of low cross linked resins differed from that of monovalent counter ions.

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Copolymerization of acetaldehyde (AA) and n-butyraldehyde (BA) was carried out in toluene with Et₂AlNPh₂ with an initial monomer composition of AA/BA=6/4. The following equation was obtained with a copolymer (54 mol% of AA unit) by light scattering method.
[η] =5.13×10^-4M^0.65 (toluene solution, at 30°C)
DP of copolymer obtained at -78°C was directly proportional to the molar ratio of polymerized monomers and catalyst. This indicates that the type of copolymerization reaction belongs to that of “living polymerization”.
The ceiling temperatures at total monomer concentration of 3.71 mol/l were determined to be-55°C, -45°C and-54.5°C for AA, BA and the monomer mixture of AA/BA =6/4, respectively. The final yield of copolymer was decreased with raising polymerization temperature and independent of catalyst concentration. When the reaction mixture was cooled to-78°Cafter standing at-60°C for 2 hr, the amount and the intrinsic viscosity of copolymer reached approximately the same values as those obtained by the polymerization at-78°C. But when the reaction mixture was warmed to 0°C after standing at-60°C for 2 hr, the amount and the intrinsic viscosity of copolymer were gradually decreased with the lapse of time. These results suggest that the reaction systems are in polymerization equilibrium.

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Copolymerization of acetaldehyde (AA) and n-butyraldehyde (BA) was carried out at-78°C with various amounts of water. The effects of water on the total yield of polymer obtained after 24 hr and on the initial rate of polymerization in the presence of Et₂AlNPh₂ as a catalyst were investigated comparing with the case using Et3Al as a catalyst.
In the case of Et₃Al-H₂O system, the total yield of polymer and the initial rate of polymerization gave the maximum value at the molar ratio of H₂O/Et₃Al of about 0.5 when the monomer compositions of AA/BA were 10/0 and 6/4. But, a maximum value was not observed at the feed compositions of AA/BA=4/6 and 0/10.
In the case of Et₂AlNPh₂-H₂0 system, the total yield of polymer and the initial rate of polymerization decreased gradually with an increase of the molar ratio of H₂O/Et₂AlNPh₂.
A difference of initiation mechanism of the polymerization in both catalytic systems was also discussed from the obtained results.

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