In Situ Generation of Nanosilica in a Plasticiser

Filler loading often dramatically alters elastomer properties. Smaller the filler particle, better the reinforcement of the rubber. Recently, nanoparticles like nanosilica are studied intently as a probable reinforcement for rubbers.  However, there are some  complications accompanying nanofiller addition like aggregation and agglomeration of  the filler particles,  causing loss of strength. In this present work, preparation of a process- feasible  silica dispersion (in situ, in Olive Oil mediium) for rubber is described, The nano silica dispersion was prepared by sol gel method by reacting tetraethoxysilane (TEOS) with water in a liquid (Olive oil) medium. The dispersion thus prepared, was added to NR gum and filled(with HAF black) compounds in a two roll mill. By this way, the rubber compound is expected to attain uniform distribution and dispersion of SiO₂ nano particles, which in turn, should increase the mechanical properties of vulcanizate. Our studies show some improvement in mechanical properties due to the presence of the nano dispersion in the compound. SEM studies were also done on the fractured tension test specimens and an attempt is made to correlate the dispersion with the improvement in the properties. Further, we also check if there is a synergy between the nano silica and the carbon black in the compounds leading to better mechanical properties.

Keywords:  in-situ generated NANO silica, sol gel method, SiO₂ dispersion Olive oil, mechanical properties.