Fremgangsmåde til genvinding af elastomermateriale

摘要

A process of recycling used sulphur-cured elastomeric materials comprising masticating the said elastomeric materials at temperatures preferably below 50 DEG C with a novel chemical mixture which is capable in a controlled manner of opening up or delinking the vulcanised network of the elastomeric materials. The novel chemical mixture is made from the zinc salt of dialkyl dithiophosphates and mercaptobenzothiazole or other accelerators in the molar ratio for example in the range of 1:1 to 1:12 dispersed in diols and in the presence of zinc oxide and stearic acid. This mixture, which may be termed the 'Delink' when blended with tyre crumbs or any other vulcanised crumbs in concentrations of 6 parts binder per 100 parts of rubber crumbs on a mill effectively delinks the vulcanised network and renders the compound ready for moulding and vulcanisation without the need for further cross-linking chemicals. The total milling period, which occurs at temperatures preferably below 50 DEG C, takes only 7 to 10 minutes. Alternatively, the binder and tyre crumbs could be first mixed in an intermix and subsequently milled in an open mill. The obtained recycled rubber compounds display satisfactory levels of physical and dynamic characteristics. Such compounds can be directly used in moulded goods or in admixture with fresh compounds in tyres and related areas.