Enhancing the Performance of Rubber with Nano ZnO as Activators

Abstract

The vulcanization of rubber is a chemical process to improve the mechanical properties by cross-linking unsaturated polymer chains. Zinc oxide (ZnO) acts as an activator, boosting the rubbers’ sulfur vulcanization. Maintaining the level of ZnO content in the rubber compounds as low as possible is desirable, not only for economic reasons but also to reduce the environmental footprint of the process. In this contribution, octylamine (OA) capped ZnO nanoparticles (5 nm diameter), prepared through a thermal decomposition method, were demonstrated to be efficient activators for the sulfur vulcanization of natural rubber, enabling the reduction of the required amount of ZnO as compared to commercial systems. The effect of different ZnO activators (OA capped ZnO/commercial indirect process ZnO) on the curing characteristics, cross-linking densities, and mechanical performance, as well as the thermal behavior of rubber compounds, were investigated. Compared to the commercial indirect process ZnO, OA capped ZnO nanoparticles not only effectively enhanced the curing efficiency of natural rubber but also improved the mechanical performance of the composites after vulcanization. This was interpreted as, by applying the OA capped ZnO nanoparticles, the ZnO levels in rubber compounding were significantly reduced under the industrial vulcanization condition (151 °C, 30 min).

Enhancing mechanical performance and wet‐skid resistance of emulsion styrene butadiene rubber/natural rubber latex composites via in‐situ hybridization of silanized graphene oxide and silica

“…This is because the interaction of hybrid fillers with accelerator CZ and activator ZnO promote their dispersion in rubber matrix and accelerate the rapid formation of sulfur bonds between rubber molecular chains. 33 1# has the largest optimum cure time (t c90 ), which is because the agglomeration of SiO 2 causes uneven dispersion in the composite material. 34…”

Synthesis and Applications of ZnO/Polymer Nanohybrids

“…198 A recent research demonstrated the usage of 5-nm OA-capped ZnO nanoparticles in the vulcanization of natural rubbers. 199 Compared to commercialized ZnO, OA-capped nanosized ZnO exhibited significantly better dispersion in a rubber matrix and effectively improved the curing efficiency of natural rubber, which potentially could have a great impact on reducing ZnO loadings in commercial rubber manufacturing. Also, ZnO has been increasingly applied in the area of photocatalysis, because of its prominent photocatalytic activity.…”

“…ZnO plays an important role in promoting the formation of sulfide cross-links and improving the kinetics of the curing process, thus achieving higher cross-linking densities in rubbers . A recent research demonstrated the usage of 5-nm OA-capped ZnO nanoparticles in the vulcanization of natural rubbers . Compared to commercialized ZnO, OA-capped nanosized ZnO exhibited significantly better dispersion in a rubber matrix and effectively improved the curing efficiency of natural rubber, which potentially could have a great impact on reducing ZnO loadings in commercial rubber manufacturing.…”

Fabrication of zinc oxide‐coated microcrystalline cellulose and its application in truck tire tread compounds

“…Nowadays, the reduction of ZnO content in rubber products can be achieved through various methods, that is, (1) the utilization of nanosized ZnO, [33][34][35][36] (2) the replacement of ZnO with zinc-based curing agents, [37][38][39][40][41] and (3) the synthesis and usage of composite ZnO produced by depositing ZnO on various supporting cores. [42][43][44][45][46][47] The last one seems to be a promising method to effectively reduce the composition of ZnO and produce the more eco-friendly material.…”