Potential of crystalline nanocellulose (CNC), as green reinforcing filler, has been evaluated for the preparation of natural rubber (NR) composites. CNC is derived from a natural source (ramie fiber) and its surface is modified with different organosilanes to strengthen the rubber‐filler interaction at the interface. It is found that, although at 2.5 phr (parts per hundred parts of rubber) loading of CNC the mechanical property of the NR composites is improved, it deteriorates at 5 phr loading. Surface modification of CNC by organosilanes is found very useful to overcome this issue. The modulus values at low strain become almost 1.5 to 2 times higher while tensile strength becomes 2.5 times higher for the modified CNC filled composites relative to those of CNC filled composites at 5 phr loading. These results are corroborated with a morphological study, where a very good state of dispersion of CNC particles is found in the surface‐modified CNC filled composites. Moreover, the particle size of CNC becomes almost half, in respect to that of unmodified CNC particles, upon surface modification by organosilane. The reinforcement effect delivered by CNC and surface‐modified CNC is also reflected by a small positive shift in Glass Transition Temperature (Tg) in differential scanning calorimetry study.

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Synergistic effect of MWNT induced reinforcement and high energy radiation induced crosslinking on the physico-mechanical and thermal characteristics of polychloroprene rubber (PCR)/ethylene-propylene diene rubber (EPDM)/MWNT elastomeric nanocomposites was investigated. The extent of reinforcement, as assessed using the Kraus equation suggested high reinforcement of the blend on MWNT addition; though, the thermal stability and glass transition of the PCR and EPDM components were not significantly affected by MWNTs. The elastic modulus increased with the radiation dose as well as with the increase in MWNT content. The reinforcing mechanism of the nanocomposites was studied by various micromechanics models all of which predicted higher moduli than the experimentally observed results, indicating agglomeration in the nanocomposites. Nevertheless, in all the composites synergistic effect of radiation crosslinking and MWNT induced reinforcement were seen, suggesting radiation induced crosslinking between polymer and MWNT interface.

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Zirconia particles are generated into a nitrile rubber (NBR) matrix via a solution sol–gel method in a controlled manner. Formation of zirconia particles from their precursor (zirconium­(IV) propoxide) occurs under optimized reaction conditions. As a result, the nanoparticles are embedded and well dispersed in the NBR matrix that results in a remarkable improvement in mechanical and thermal properties of the composite. Such reinforcement is not realized when the composites are prepared following the conventional technique of filler loading by physical mixing, although the filler content remains the same. Use of a surface active coupling agent TESPT (bis-(3-triethoxysilylpropyl) tetrasulfide) in the reactive sol–gel system is found to further boost the mechanical performance of the composites. In order to ensure the practical application of the developed composites, a series of studies have been performed that consist of dynamic performance, swelling, thermal degradation, and resistance to oil, ozone, and abrasion. Analysis of the results reveals that in situ zirconia could be an excellent filler for the NBR composites to withstand in a harsh and adverse environment.