In the presence of furnace black (HAF) treated with agents such as benzoyl peroxide (Bz₂O₂), 2, 2-diphenyl-l-picrylhydrazyl, nitrous oxide, diazomethane, hydrogen peroxide and nitric acid, the products obtained by the reaction of ethylene glycol with Bz₂O₂ at 45°C have been examined and compared with those of the untreated HAF. The saponification of Bz₂O₂- treated HAF to convert benzoate group into surface phenolic hydroxyl has also been carried out to examine the extent of the ability to cause the C-C bond cleavage of the glycol using the resulting carbon black.
In many cases it is found that the treated carbon blacks show decrease in the ability to cause the C-C cleavage in compared with that of the untreated HAF. For example, in the presence of treated samples with Bz₂O₂, nitrous oxide and nitric acid, the oxidation of the glycol with Bz₂O₂ gives mainly acetaldehyde. However, in the presence of the hydrolyzed sample, the recovery of a greater part of ability to convert the glycol into formaldehyde is observed.
The results indicate that the benzonoidal rings and a part of phenolic hydroxyl groups present at the edge of micrographitic platelets on carbon black surface may be responsible for the C-C bond cleavage reaction.

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Five vulcanizing agents, trithiocyanuric acid-MgO-diphenylguanigine (I), 2-mercaptoimidazoline-Pb₃O₄ (II), hexamethylenediamine carbamate-Pb₃O₄ (III), 2-di butylamino-4, 6-dimercapto-s-triazine-MgO (IV), and 2-mercaptoimidazoline-PbS-S-MgO (V) were used to compare the heat aging resistance of vulcanizates in regard to the degree of crosslinking, gel fraction, and the volume of oxygen absorbed at 175°C. From the observation of above results as well as the retention of mechanical properties after air oven aging test at 160°C, the thermal stability of the vulcanizates was found to increase in order of (III) < (II) < (V) < (IV) < (I). Thermal-oxidative degradation mechanisms were discussed on the four types of crosslinkage, thio-s-triazine, monosulfide, bis-aminoalkyl, or polysulfide formed by the vulcanizing agent, (I, IV), (II), (III), or (V) respectively. The vulcanizates were stabilized by the addition of the antioxidants such as nickel dibutylditiacarbamate, 2-mercaptobenzimidazol or phenyl-β-naphtylamine.

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In order to study on the filler effects of xonotlite (6CaO. 65iO₂. H₂O; needle crystals) on polyvinyl chloride (PVC), mechanical properties, such as tensile strength, Young's modulus and impact strength were measured on the non plasticized PVC and plasticized PVC containing 10, 20 and 40 phr of xonotlite, respectively.
Two kinds of xonotlite of different crystal lengths were prepared by hydro-thermal treating of calcium oxide and natural silica powders, and blended into PVC. The sheets for test pieces were made from the compounds using mill and press.
The xonotlite showed superior reinforcing effects as compared with surface treated fine calcium carbonate on tensile strength and Young's modulus, but resulted in the drop of impact strength. Better reinforcing effects were obtained with small crystals rather than large crystals.
The handy method using triangular graph was offerred to evaluate the effects of filler on the mechanical properties of the resin.

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