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The copper catalyzed reaction of silicon metal powder with hydrogen chloride by flow method was studied in order to find a convenient preparative method of chloropolysilane, and also to elucidate the mechanism of this reaction. This reaction was found to start at about 170∼230°C, and once the reaction occurred, the contact mass is activated and the reaction takes place even at 170°C. When the most adequate conditions were adopted, chloropolysilanes were obtained in the condensate as efficiently as 30 wt.% yield based on hydrogen chloride. As to the mechanism of the reaction, it seems to be plausible that the first step of the reaction is an attack of hydrogen chloride on aluminum which is usually present in the commercial silicon metal. The second step is the reaction between silicon hydride, which is derived from the first step reaction upon the silicon contact mass and metallic copper forming the silicon-copper bonding. The third step is the cleavage reaction of copper-activated silicon by hydrogen chloride to produce chlorosilanes under the presence of aluminum chloride. The aluminum chloride is also derived from the first step reaction, and copper is regenerated in metal form which can circulate among the latter two reaction steps as long as the effective silicon component is present.

This paper concerns the hardening mechanism of urushi lacquer. The author wished to propose an entirely new mechanism for the room-temperature hardening of urushiol in this natural resin. An investigation of the unit reactions correlated to the mechanism indicated that the catechol moiety of urushiol and metalhydroxides play an important role in hardening. According to the results, the structure of one component of urushiol as “acetone powder”, obtained from raw urushi sap, was clearly determined. On this basis, it is disclosed that the polymerization of urushiol does not depend on the opening of the sesquiterpene double bond, but is mainly associated with a new type of inorganic ionomer bonding, such as silanolate and carbohydroperoxide–calcium hyroxide, –magnesium hydroxide or –other metal hydroxide combinations’ hydrogen bonding bridges with the urushiol matrix.

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Polymethylhydrosiloxane was added to the Ziegler catalyst in propylene polymerization, and a kinetic study carried out for this system was in good agreement with the results obtained in the polymerization carried out in an autoclave under pressure. The experimental equations for polymerization rate are for constant siloxane and AlEt3 concentrations and for constant siloxane and TiCl4 concentrations, where α, A, and β are constants. From experimental results of studies of the chemical properties of polymethylhydrosiloxane, a reasonable reaction mechanism was proposed which can explain the experimental results in the polymerization process. The polymers were separated by use of several solvents, and both the residue and extracted parts showed the presence of silicon. On the basis of chemical analysis and infrared absorption spectra, it was concluded that the polymers obtained were copolymers of polypropylene and polymethylsiloxane.