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Elastomers, usually, are reinforced with reinforcing filler in order to improve their mechanical properties like tensile strength and abrasion resistance. The efficiency of this reinforcement is correlated with different factors like filler structure, surface area, and polymer-filler interactions. This study presents a methodology to quantify the bound rubber attached to the reinforcing filler silica using the thermogravimetric analyzer. Three typical rubber compounds used in tread tire were studied. In the samples tested, the silica content was kept constant, varying only the percentage of the coupling agents. Considering the results of the thermal analysis, physical, mechanical, and rheological tests, the thermogravimetric analysis has proved to be a very useful technique in evaluating the interaction of filler and polymer.

Industry is constantly demanding for materials with differential properties that explores nanoscale fillers functionality. Unfortunately, most of the papers present processing methods that are hard to scale up. Effects in addition different amounts of multiwall carbon nanotubes (MWCNT) and few-layer graphene (FLG) on cure behaviour, viscoelastic, mechanical and electrical properties of a hydrogenated nitrile butadiene rubber (HNBR) are investigated and compared with those composites having carbon black (CB) as filler. Looking for scale up the produced nanocomposites, rubber composites were produced in a closed mixing chamber by melt mixing with unmodified fillers. Addition of nanotubes reduces curing time. Microstructural analyses indicate that FLG cannot be easily dispersed by this methodology. Significant improvement in mechanical properties is observed with MWCNT addition, with 940% modulus increment regarding to the pure polymer and also, in lower intensity, in HNBR/FLG composites. Moreover, HNBR/MWCNT composites presented a sharp reduction in electrical resistivity at low loading level.

Thermoplastic vulcanizates (TPVs) are a class of polymeric material obtained by dynamic vulcanization of an elastomer in a melted thermoplastic matrix. This work intend to evaluate different variables in the production of low hardness TPVs made of polypropylene (PP) and ethylene propylene rubber (EPDM), as well the optimization of the variables looking for TPVs with improved performance. In the Study I the influence of PP crystallinity were evaluated, in the Study II the effects of different amounts of dicumyl peroxide (DCP) were evaluated and in the Study III the amount of the phenolic resin were evaluated. This extended abstract presents, in a more detailed way, the results considering the curative phenolic resin content (Study III). The others results and discussions are briefly described in the results and discussions section. The compounds were obtained in a closed mixing chamber and their processability properties, swelling, hardness and tensile strength were evaluated. With the results obtained were possible to evaluate the influence of different ingredients in the TPVs properties. The results were discussed and presented looking for a better understanding of the influence of this variable in the final product, as well the correlation between then.