Surface modification of zirconia by various modifiers to investigate its reinforcing efficiency toward nitrile rubber

Abstract

AbstractUniform dispersion of metal oxide‐like zirconia in elastomeric matrix is an essential requisite to deliver proper reinforcement. However, inadequate compatibility between the hydrophobic elastomer and the hydrophilic zirconia surface makes this a difficult task. In this work, three different surface modifiers, namely, sodium dodecyl sulfate (SDS: a surfactant), 3‐(trimethoxy silyl) propyl methacrylates (MPS: an organosilane), and tris (hydroxymethyl) aminomethane (Tris: an amine buffer) are employed to modify the surface of sol–gel derived in‐situ generated zirconia. Effect of surface modification of zirconia by these different kinds of surface modifiers on zirconia‐filled nitrile rubber (NBR) composite has been critically investigated in terms of thermal, morphological, mechanical, swelling, rheological, and dielectric properties. Temperature of maximum degradation (Tmax) of the NBR gum (439 °C) is improved upon incorporation of all type of modified zirconia while that is maximum for Tris‐modified zirconia‐filled composite (458 °C). Similar trend is observed in stress–strain study where Tensile strength is enhanced up to six times for the filled composites relative to NBR gum (1.03 MPa) and the highest value is shown by Tris‐modified zirconia‐filled composite (6.35). This study reveals that Tris could be a potential surface modifier for metal oxides like zirconia, as an alternate to organosilane, to reinforce the elastomer matrices.