Eco‐friendly composites derived from naturally occurring molecules in promoting dispersion of nanosized silica particulates

Abstract

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