Graft copolymerization of methacryloyl glycine (M-Gly) and methacryloyl glycine esters (M-Gly-OR) onto natural rubber was investigated using benzoyl peroxide (BPO) and azobisisobutyronitrile (AIBN) as radical initiators under various conditions. Several physic chemical properties of graft copolymers obtained were also examined.
Graft copolymerization of M-Gly : 1) As a polymerization solvent the mixture of toluene and dioxane with the composition of 1 : 1 to 2 : 1 by volume was suitable. 2) BPO was effective as an initiator and its optimum concentration was 3.125 x 10^-3 mole/1. If AIBN was used, a homopolymer was obtained almost exclusively and graft polymerization hardly occurred. 3) With a higher rubber concentration and the use of 0.015 mol monomer against 0.01 mol rubber (polymerization temperature : 80 °C) good result was obtained in t he grafting. 4) The appropriate polymerization temperature was 60 to 80 °C, but a very long time was needed at 60 °C. Irradiation with light instead of heating was also effective. 5) As the degree of grafting increased, the polymer obtained became more easily swollen in water but hardly swollen in benzene and carbon tetrachloride.
Graft copolymerization of M-Gly-OR : 1) BPO was an effective initiator as in the case of M-Gly. 2) The optimum polymerization temperature was 100 °C, and if the temperature was lower, graft copolymerization hardly occurred. 3) The graft copolymer obtained became softer as the carbon number in ester groups of monomers increased.

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For some engineering purposes a power function representation of the results is more convenient in testing rubberlike polymers than the analytical expressions hitherto used in this series of study. A general form of the power function representation is given by
(Z/Z) ≅ [IIiP^αi_i] {IIjQ^βj_j}
Here (Z/Z), P and Q are the normalized response, material parameter and excitation parameter, respectively, and they can all be defined with the JSR 12 const. model proposed previously. Both α and β are exponents. An example of this type of representation is given for the heat build-up obtainable with the Goodrich flexometer.
It is then pointed out that the conversion of the expression from analytical to power functional does not necessarily result in a loss of accuracy.
Finally, a statistical method for estimating the values of the exponents is suggested for some complicated phenomena to which the application of various analytical methods appears to be impractical.

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The polysulfide formation reaction between epichlorhydrin, (ECH) and Na_xS_y was studied. As the result of consumption measurements of Na_xS_y in reaction system, it was proved that this reaction was rapid and easy. In a reaction at 90°C, the molecular weight of the product was large and the chlorine content was zero. In the case of a reaction with sodium polysulfide instead of sodium sulfide, a product with high content of sulfur was obtained. As for the effects of additives in the reaction system, with the exception of decrease in yield of product under addition of ethylenediamine, the addition of sodium hydroxide, organic solvents, phenol etc., produce small effects upon the yield, sulfur and chlor content of products, and the rate of this reaction. Comparative reactivities of ECH with the other dihalogenated compound were the same as that of ECH with, a, γ-dichloroglycerin to and were larger in the order of α, γ-dichloraceton, 1, 2-dichloroethane.

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The diffrences between 1, 4-hexadiene (1, 4-HXD) -EPDM and ethylidenenorbornene (ENB) -EPDM as tread polymers were studied putting emphasis mainly on processability, abrasion resistance and flex crack resistance.
In order to eliminate other factors and clarify the differences between termonomers, molecular weight or composition fractionation, polymerization under the same conditions and blend of polymers were performed.
And it was found that there is not any particular diffrence between ENB-EPDM and 1, 4-HXD-EPDM in hardness, 300% modulus, tensile strength, elongation, resilience, heat build-up and skid resistance when polymers of the same molecular structural factors such as molecular weight and composition distribution are compared. But ENB-EPDM was found to be inferior to 1, 4-HXD-EPDM in abrasion resistance and flex crack resistance. These differences might be ascribable to structures of crosslinkage, branching degree and other structural factors of higher orders in which termonomers play an improtant roll, and further studies are required to clarify the relation between these differences and termonomers.

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This work has been carried out to get a clue to knowing the reason why polyethylene-filled hard clay could not be crosslinked with Dicumyl Peroxide (DCP). From the results, it was considered that DCP decomposed as an ionic mechanism on hard clay surface.
The reaction of DCP and hard clay was performed in CCl₄ to investigate the ionic decomposition compounds. Its decomposition compounds were identified as phenol, acetone and 4-methyl-2, 4-diphenyl-2-pentene.

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