Structure–Property Correlations of SSBR/BR Blends

During the reported project work, ca. 200 different SSBR and SSBR/BR vulcanisates were produced and investigated. During compounding, for each mixture, various processing-related parameters were recorded. Afterwards, the vulcanisation behaviour was characterised by using vulcametry and the last step was to quantify the mechanical and fracture mechanical properties by selected methods. The general aim was to optimise the material properties regarding a possible application in car tires. Mainly, the type of polymer, type and content of filler as well as the surface modification of the used alternative filler TROVO®powder were varied to get a preferably balanced property level. It could be stated that the different main components of the rubber mixture (polymer, filler, coupling agent) have a large influence on the physical properties. Basing on the results, most promising combinations of polymer and filler were defined and further investigated. It was found that the silica filler can be replaced by maximal 10 phr TROVO®powder BK3 without loss in application-related properties or to get an increase in properties, respectively. From the processing-related properties, it could be concluded that due to the reduced polymer filler interaction, the processing requires less energy to get a homogeneous mixture. This can be an advantage. Further, for some application-related properties such as tear strength, an increase due to the substitution of small amounts of silica by TROVO®powder BK3 was observed. This means, TROVO®powder BK3 can contribute to an enhancement of the processing behaviour. Due to the large particle size and the low specific surface area, only small amount of polymer–filler interaction as a basis of reinforcement can be expected. However, the surface modification of TROVO®powder with silane or zinc for example is an elegant way, to transport critical substances into the mixture and distribute them very well.