The physico-mechanical properties of variable rubber blends including epoxide natural rubber (ENR), polybutadiene rubber (BR), and solution polymerized styrene-butadiene rubber (SBR) filled with silanized silica and carbon black mixtures were explored. The tensile, hardness, resilience, abrasion, and fatigue behavior were investigated. An optimized composition involving 30 phr of ENR and 70 phr SBR filled with mixtures of carbon blacks and silanized silica was proposed to be a suitable composition for the future development of green passenger truck tires, with low rolling resistance (fuel saving ability), high wear resistance, and desired fatigue failure properties.

The market demand for elastomeric‐graphene/derivatives nanosheets (GDS) materials is high nowadays, due to their excellent physico‐mechanical properties over traditional composites. However, the curing behavior of elastomeric‐GDS which influences the overall properties and also determines the cost of related products has not been well investigated. Previously, the curing properties of NBR‐graphene oxide (GO) and NBR‐reduced graphene oxide (rGO) was studied and the curatives (accelerator and activators) were suspected to have influence on their curing behavior. This study explores the curing behavior of NBR‐GO and NBR‐rGO in the absence of tetramethylthiuram disulfide (TMTD) accelerator. The virgin NBR exhibited shorter curing periods with higher curing rates (CRI) than the composites. The measured CRI showed close correlation with the activation energy Ea, deduced from Ozawa and Kissinger kinetics models. The NBR‐rGO composites showed shorter scorch time and lowered Ea at higher temperatures, with increased tensile properties than NB‐GO composites. Despite the delay, the composites exhibited high strength over the virgin NBR, due to tighter networks introduced by rGO and GO sheets within NBR. Therefore, future design of elastomer‐GDS‐based composites must involve a careful control of the amounts of the accelerator‐/co‐accelerator‐like TMTD in the mixtures for improved physico‐mechanical properties of the final product.

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The use of the principle of maximum entropy generation per unit volume is a new approach in materials science that has implications for understanding the morphological evolution during solid–liquid interface growth, including bifurcations with or without diffuseness. A review based on a pre-publication arXiv preprint is first presented. A detailed comparison with experimental observations indicates that the Maximum Entropy Production Rate-density model (MEPR) can correctly predict bifurcations for dilute alloys during solidification. The model predicts a critical diffuseness of the interface at which a plane-front or any other form of diffuse interface will become unstable. A further confidence test for the model is offered in this article by comparing the predicted liquid diffusion coefficients to those obtained experimentally. A comparison of the experimentally determined solute diffusion constant in dilute binary Pb–Sn alloys with those predicted by the various solidification instability models (1953–2011) is additionally discussed. A good predictability is noted for the MEPR model when the interface diffuseness is small. In comparison, the more traditional interface break-down models have low predictiveness.

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