Reactions of Synthetic Rubbers in Supercritical Water
Solution and Interface Chemistry, Institute for Chemical Research, Kyoto University, Kyoto
Nippon Gomu Kyokaishi,(2004),77(10),365-371 General Review in Japanese

This review on supercritical water reactions of rubbers is composed of the following chapters: 1) Introduction, 2) Synthetic Processes in Hot and Supercritical Water Complementary to Photosynthesis, 3) What Is Supercritical Water? 4) Rate-Controlling Factors of Supercritical Water Reactions, 5) Chemical Bonds Composing Rubbers and Their Reactivity, 6) Reactions of Synthetic Rubbers Studied in Supercritical Water, and 7) Future Problems. The importance of the development of science and technology of supercritical water reactions are emphasized in relation to green chemistry. It is shown that hydrothermal reactions of used rubbers and other organics is investigated in order to conserve chemical bonds, such as C-C, C-H etc. contained in rubbers, instead of their oxidative degradation by burning. Learning from chemical evolution on the primitive earth, thus we hope that hydrothermal synthesis can replace photosynthesis as much as possible to avoid the energy crisis of the 21st century. For recycling styrene-butadiene and ethylene-propylene rubbers, several works have been carried out in sub- and supercritical water. Used rubbers can be converted to useful organic compounds. Ethylene-propylene rubbers are cracked to paraffin oils, while styrene-butadiene rubbers are transformed into benzene and its derivatives.

Supercritical Water, Rubber, Green Chemistry, Bond Conservation