Abstract
Powdered rubbers of scrap passenger tires(20mesh)were heated at300-330°C without oxygen in an autoclave to give carbon black and oil.The properties of the recovered carbon black were almost the same as those of SRF carbon.The results of analysis of the oil showed that some unsaturated hydrocarbon existed.
On the other hand, BR or SBR was heated to examine the thermal degradation process in an autoclave in the same manner as powdered rubber. Both BR and SBR hardened at 200-250°C and degraded at 300°C. As a whole, vulcanized rubber tended to degrade at lower temperature than unvulcanized one.The results of analysis of the degraded oil of BR showed that some unsaturated parts and cyclized parts existed in it.In the case of the thermal degradation process of BR, isomerization from cis-1, 4to trans-1, 4, cross-linkage, and degradation seem to occur with increasing temperature.The cyclized parts seem to form at the step of crosslinkage and degradation.The thermal degradation process of powdered rubber also seem to be the same as the case of BR.
