Synthesis and effect of surface modified nano ZnO in natural rubber vulcanization

Abstract

It is well known that surface of ZnO acts both as a reactant and a catalytic reaction template in rubber vulcanization by activating and bringing together reactants. The particles of accelerators, fatty acid, and sulfur diffuse through the polymer matrix and get adsorbed on the surface of ZnO, forming intermediate complexes.Hence dispersion of ZnO in the elastomer matrix is a determining parameter. Capping is one of the novel techniques for increasing ZnO-stearic acid/accelerator interaction, thereby enhancing their activities. During the sol-gel precipitation of nano ZnO, if a suitable capping agent is added, agglomeration of ZnO particles gets reduced, leading to the formation of nano particles. Since only very few studies are found reported on synthesis of acceleratorcapped ZnO and its application in rubber vulcanization, attempts have been made in this study to synthesize our novel accelerator N-benzylimine aminothioformamide (BIAT)-capped-stearic acid-coated nano ZnO (ZOBS), and BIAT-capped ZnO (ZOB) to investigate their effects in natural rubber (NR) vulcanization. Efforts have also been made to synthesize stearic acid-coated nano zinc phosphate (ZPS) with an aim to find an alternative to conventional ZnO in vulcanization. Mechanical properties like tensile strength, tear resistance, abrasion resistance, and compression set were found out. Swelling values of the vulcanizates as a measure of crosslink densities were also determined. Optimum dosage of ZOBS and a combination of ZOB and ZPS were also derived and found that capped ZnO is superior in NR vulcanization to conventional ZnO in improving cure properties including scorch safety and mechanical properties.

Preparation of zinc‐oxide‐free natural rubber nanocomposites using nanostructured magnesium oxide as cure activator

“…Environmental protection agency has classified ZnO as hazardous chemical for the environment and has suggested that its application in rubber compounds should be reduced . To solve this environmental problem, very recently several studies have been made by different researchers for the reduction of ZnO level in rubber vulcanization by introducing nano ZnO as cure activator. Sahoo and Bhowmick reported that nano ZnO is much more effective curing agent for carboxylated nitrile rubber (XNBR) in comparison to conventional ZnO.…”

A functional modified graphene oxide/nanodiamond/nano zinc oxide composite for excellent vulcanization properties of natural rubber

“…They inferred that this may be related to the formation of more crosslinked precursors, due to the high specic surface area of nanoZnO. 11,12 Recent works have focused on the use of nanoZnO to partially or completely replace conventional ZnO for rubber vulcanization. Due to the nanometer effect of nanoZnO, it can signicantly improve the vulcanization performance of rubber and the utilization rate of rubber vulcanizing agent with a small amount of addition.…”

The dynamic mechanical properties of magnetorheological elastomer: Catalytic effect of carbonyl iron powder

“…Magnetorheological elastomers (MREs) are a class of smart material whose modulus and damping ratio can be rapidly and reversibly controlled under magnetic field. Zinc is a very important role in MREs, which is usually added to the vulcanization reaction system in the form of ZnO (Ndayishimiye et al, 2020; Nie et al, 2020; Thomas et al, 2012). The chemical properties of iron and zinc are similar and lively.…”