Reinforcement of natural rubber using ahybrid filler derived from mineral silica and In-situ precipitated silica

Abstract

This research was conducted to optimize the mechanical properties of Natural Rubber glove material with mineral silica and in-situ precipitated silica fillers. Doubled Centrifuged natural rubber Latex with 60% dry rubber content which was stabilized by ammonia and mineral silica which were ground using “TEMA mill” and sieved to get particle sizes in the range of 40–65 µm were used. In-situ precipitation was done using tetra- ethylorthosilicate and a base catalyst. A standard formulation that is used in industry to produce gloves was used as the glove formulation. Three series of samples were prepared with increasing the mineral percentage by weight. Series A was prepared by adding mineral silica which has random particle sizes less than 65 µm. Series B was prepared by adding mineral silica which has particle sizes in the range from 40-65 µm and the series C was prepared by adding 1:1 ratio of mineral silica (particle sizes in the range from 40–65 µm) and in-situ precipitated silica. Determination of mechanical properties of the samples was based on the tensile and tear strength tests. Series A and B had same pattern of tensile and tear strength results, but optimum filler percentages were different. In series A, the sample containing 2% filler had optimum mechanical properties, while in series B, the sample containing 3% filler had optimum mechanical properties. In series C, the pattern was different and optimum filler composite was the sample with 5% silica. Further characterization was done with Thermogravimetric Analysis.