Application of Silica Powder in Rubber
In order to improve the physical and mechanical properties of rubber products and extend the service life of rubber products, two approaches are generally adopted: one is to embed skeleton materials such as fiber textile materials or metal materials in rubber products; the other is to add various fillers to rubber.
Silica powder as a rubber reinforcement material has the following forms:
(1) Powdered quartz. It is mainly made of natural diatomaceous earth, which is crushed, calcined at high temperature, and organic impurities are removed. It can be used in rubber to make the rubber firm, reduce the density of the rubber, and increase the thermal insulation performance. It is suitable for the manufacture of insulating rubber, model products, and foam products. It can be used in hard rubber to increase the softening temperature.
(2) Silica powder. The silica content is 75% to 79%. It is made from natural minerals through mining, drying, crushing, and screening. It can be used for hoses, tapes, and other rubber products. The filling rubber is easy to mix and has good dispersibility. It can be filled in high quantities. The surface of its calendered products is smooth. The strength and elongation of its vulcanized rubber are close to clay and equivalent to light calcium. Its adhesion strength and tearing permanent deformation are better than clay, and its wear resistance and elasticity are better than clay and light calcium. It has good aging performance and is cheaper than clay and light calcium.
(3) Quartz powder. Quartz powder has different types, such as amorphous and microcrystalline. It is processed by crushing natural minerals.
In terms of specific applications, powdered quartz is added to replace clay and light calcium carbonate in the battery rubber shell, and the filling amount is increased from the original 55% to 65%. In addition, the process performance is excellent, the rubber absorbs powder quickly, there is no powder spraying and flying phenomenon, it is easy to mix and rub, and the vulcanization performance is good. The physical and mechanical properties of the battery rubber shell, such as acid resistance, voltage resistance, thermal deformation, and falling ball impact, can meet the requirements, and the surface of the rubber shell is flat and smooth, and the yield rate is improved.
In rubbing rubber products, the mixed rubber filled with powdered quartz has thin rubber, good permeability, and strong adhesion, which is conducive to the rubbing of the mixed rubber on the canvas, and enhances the adhesion strength between the film and the canvas. The mechanical properties of the product, such as tear strength and permanent deformation, are significantly improved.