チオール及びアミン化合物による古タイヤゴムの化学再生

Abstract

The reclamation of crushed tire scrap of passenger cars was carried out by a conventional mechano-chemical procedure with organic thiol and amine compounds which are usually employed as an accelerator, antioxidant and peptizer for vulcanizates. Consequently, 2-mercaptobenzothiazole and its cyclohexylamine salt were found to be the more effective reclaiming agents. From the swelling measurement of SBR vulcanizates in benzene solution containing a small amount of thiol and amine compounds as a reclaiming agent, it was that thiophenol, pchlorothiophenol, n-butylamine and dimethylamine contributed considerably to the degradation of vulcanizates. Moreover, the thiol-amine complex was found to serve remarkably as a breaker of crossliking which is presented in the form of di-and poly-sulfide linkages. These reclaimed rubbers obtained by the mechano-chemical procedure with thiol and amine compounds have low Mooney viscosity and these re-vulcanizates show the excellent tensile properties. Especially, the re-vulcanizates having the tensile strengt of 170kgf/(cm)^2 were obtained by the use of the reclaiming agents composed of thiophenol and n-butylamine or morpholine.