Mineral Powders for the Rubber Industry

The rubber industry is one of the largest consumers of mineral powder fillers in India, and at Ridhi Sidhi Microns, we have been supplying premium-grade mineral powders to rubber manufacturers across the country for over four decades. Our mineral fillers play critical roles in rubber compounding — from reducing compound cost to improving mechanical properties, processing characteristics, and finished product performance. Mineral fillers in rubber compounding serve multiple functions simultaneously. They act as extending fillers that reduce the proportion of expensive elastomer in the compound, thereby lowering raw material cost per kilogram of finished rubber product. At the same time, they function as reinforcing agents that improve specific mechanical properties including hardness, stiffness, tear resistance, abrasion resistance, and dimensional stability of the vulcanized rubber. Our calcite powder (calcium carbonate) is the most widely used filler in rubber compounding. It improves compound hardness and stiffness while maintaining acceptable elongation and flexibility. At loading levels of 50–200 phr, calcite provides significant cost reduction without compromising the essential mechanical properties. Dolomite powder offers distinct advantages with its combination of calcium and magnesium carbonates. The higher hardness provides better reinforcement at equivalent loading levels, making it suitable for footwear soles and industrial rubber sheets. China clay (kaolin) serves as a semi-reinforcing filler offering better improvement in tensile strength, tear resistance, and flex fatigue resistance compared to calcium carbonate fillers.