Improving the silica 'green tyre' tread compound by the use of special process additives

摘要

When mixing these,silica reinforced,SSBR/BR passenger tread compounds the best silane coupling is achieved by a special mixing procedure.In this procedure only the polymers,filler,silane and oil are mixed in the first stage followed by a second stage mix when the zinc oxide,stearic acid,antidegradant and wax are added.Unfortunately,whilst this gives the best silane coupling,poor filler dispersion and silane degradation may result.There is also a problem of poor mix pick-up at the start of the remill caused by the lubricating effect of the low melting point materials added.