In this article, we provide an extensive analyses of various properties that are required for tire tread based on developed highly dispersible (HD) silica-filled epoxidized natural rubber composites. Silica in an HD form has become a staple filler in tire tread applications because of its inherent advantages. In this study, epoxidized natural rubber with 25 mol % epoxide (ENR 25) and natural rubber were mixed with two different types of HD silica for superior reinforcement. A standard tire tread formulation was used as the base compound. The magic triangle properties were conspicuously influenced by the viscoelastic characteristics of the vulcanizates. The introduction of polar rubber (ENR 25) into the HD silica greatly improved rheological, physicomechanical, bound rubber content, and dynamic mechanical properties, and this led to a better, fuel-efficient tire. We successfully achieved this, even in the absence of a silane coupling agent. ENR 25 played an imperative role in showing an extraordinary rubber-filler interactions and was primarily responsible for these observations. In this study, we explored the HD silica dispersion with transmission electron microscopy observations. Morphological studies revealed well-dispersed HD silica with the formation of a rubber-filler network.

The formation of hybrid nanostructures improves the barrier properties significantly by increasing the path of diffusion of the permeant.

Enthused by the ever growing demand for sustainable and green based materials in responding to applications based on macromolecules, an attempt was made in seeking a bio‐resin (Terpene). Herein, we report the functionalization of bio‐resin with natural rubber (NR) to produce new sustainable and greener functional polymer. Bio‐resin functionalized NR was prepared by melt mixing using di(2‐tert butyl peroxy isopropyl) benzene initiator. Structure elucidation of the bio‐resin functionalized NR was established by proton nuclear magnetic resonance and Fourier transform infrared spectroscopy, respectively. Bio‐resin functionalized NR facilitates the augmented interaction with highly dispersible silica. Amended state of highly dispersible silica dispersion has been achieved in the absence of toxic process oil, expensive silane coupling agent and conventionally used zinc oxide. Remarkable improvement in overall properties corroborated with various meticulous characterization including nanoindentation, rheological, physico‐mechanical and small angle X‐ray scattering using Becauge model, etc. The dynamic mechanical properties of the greener polymer demonstrated low rolling resistance coupled with high traction. More decisively, the macromolecule system toned up sparingly in the presence of the bio‐resin. Our contribution facilitates a novel avenue to develop sustainable high‐performance elastomeric macromolecule. Copyright © 2017 John Wiley & Sons, Ltd.

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Epoxidized natural rubber (ENR) is a modified form of NR bearing polar epoxy groups. The focus is on dispersion of highly dispersible silica (HDS) filler with three different specific surface areas in ENR 25/ENR 50 composites. The effect of three different specific surface areas of HDS on bound rubber content, Payne effect, physicomechanical properties, and viscoelastic properties of the green composites was studied in detail. Also, the influences of epoxide content in ENRs in the absence of silane coupling agent are evaluated on the overall properties of green composites. The highest level of reinforcement was obtained for the intermediate specific surface area of HDS due to the homogenous dispersion in the ENR matrix. Small-angle X-ray scattering (SAXS) has been used to analyze the particle network and cluster establishment in the green composites. The present SAXS method provides a unique insight into the aggregate formation according to the Beaucage model. On the other hand, SAXS results demonstrate that the particle network can be efficiently suppressed by increasing the specific surface area of HDS.

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The reinforcement of highly dispersible silica (HDS) in Natural rubber was hindered by their high polarity and hydrophilic surface of the filler. We addressed this challenge by developing a Terpene phenolic resin functionalized Natural rubber (TNR) coupled with epoxidized natural rubber (ENR) composites. The loading of the HDS were considered from 40 to 60 phr (parts per hundred rubber). The uniform distribution of the HDS within the rubber blends in the absence of silane coupling agent and process oil was proven by cure characteristics, physico‐mechanical properties, air ageing, dynamic mechanical analyses, Payne effect, contact angle, DeMattia flexing, dielectric properties and transmission electron microscopy. Overall, these newly developed green composites are superior to that of the reference composite, using process oil and TESPT (Bis‐(triethoxysilylpropyl) tetrasulfide) as a coupling agent. Dispersion of HDS in rubber matrix may interfere with the addition of Zinc Oxide Nano particles (Nano‐ZnO) due to the alkali‐acidic reaction. Thus, this study explores the importance of omitting Nano‐ZnO during internal mixing stage but incorporation of the same with the curing additives on a two roll mill. Our findings open up a new avenue to a fundamental understanding of HDS interaction in the novel green composites. POLYM. COMPOS., 40:871–883, 2019. © 2018 Society of Plastics Engineers

Rising ecological concerns and depletion of the potentially harmful environmental impacts caused by rubber products, are of prime importance in the industry. Therefore, implementation of sustainable greener materials is required to minimize the detrimental influences. In this research, we investigated the beneficial influence of naturally derived bio-resin toward the effects of association with Zinc Oxide Nanoparticles in highly dispersible silica (HDS) reinforced Natural rubber (NR)/Epoxidized Natural Rubber (ENR)-based composites. This novel green composite offers impressive properties which were analyzed based on bound rubber content, transmission electron microscopy, physico-mechanical, dynamic mechanical, and cure characteristics. Nanoindentation studies demonstrated the enhanced hysteresis phenomenon of the green composites. The small angle X-ray scattering (SAXS) characterization has been studied by using a Beaucage model and results corroborates that the insertion of bio-resin exhibits ameliorated state of silica dispersion in the green composites. Overall, the study with the bio-resin has provided the impetus in employing it as an alternative to the expensive synthetic route of silane coupling agent and toxic process oil.