Process for reclaiming scrap vulcanized rubber

摘要

Scrap vulcanized rubber is reclaimed by heating it under pressure with preferably 0.02 to 1 per cent of a di-(hydroxyaryl) sulphide, which may be a mono-, di- or poly-sulphide. Preferred compounds are di-(hydroxyphenyl) mono- and di-sulphides, dicresyl mono-, di-and poly-sulphides, di-(hydroxynaphthyl) di-sulphide, di-(butylhydroxyphenyl) mono- and di - sulphides, bis - (dimethyl hydroxyphenyl) disulphide, hydroxyphenyl cresyl monosulphide and cresyl dimethyl hydroxyphenyl disulphide. Oils such as pine oil extract and rosin oil may be added and also caustic soda, zinc chloride or other cellulose destroying agent if the scrap contains fibres. The process is preferably carried out at a temperature of 300-420 DEG F. till the product has a viscosity as measured on the Mooney shearing disc plastometer of 80-180 when tested at 180 DEG F.