Rubber reinforcing filler Reinforcing fillers are one of the main raw materials for the rubber industry. It can impart many valuable properties such as magnetic properties, electrical conductivity, flame retardancy, etc. It can also greatly improve the mechanical properties of rubber, improve the performance of rubber products, prolong the service life, and improve the processing performance of rubber and reduce the production cost. . Reinforcing agents used in the rubber industry are primarily carbon black, silica, silicates, carbonates, metal oxides and certain organics. Their main role is to significantly improve the tensile strength, tear strength, tensile stress, wear resistance and other properties of rubber. Fillers used in the rubber industry are mainly inorganic fillers such as talc, clay, calcium carbonate, attapulgite, and metal oxides and hydroxides. Mainly to increase the volume, reduce costs, improve the rubber processing performance. 1. Carbon black reinforcing agent Carbon black is produced by incomplete combustion or thermal cracking of hydrocarbon compounds, mainly composed of carbon elements, in the form of colloidal primary particles and aggregates of approximately spherical bodies, and has a black powder appearance. Generally processed into granular products with a diameter of 1~2mm. Carbon black is the most important reinforcing agent in the rubber industry and the second largest rubber material after raw rubber. At present, more than 90% of the world's carbon black consumption is used in the rubber industry. The degree of dispersion of carbon black in the compound affects its reinforcing properties. Experiments show that with the increase of carbon black dispersion rate, the tensile strength and Mooney viscosity of the rubber compound decrease, the tensile strength and elongation at break increase, and the crack growth slows down. Therefore, increasing the degree of dispersion of carbon black in the compound is the key to ensuring uniform texture of the rubber and excellent product properties. 2. Talc filler Talc is a natural flake mineral. The pure talc powder is a hydrous magnesium silicate composed of a sheet of brucite sandwiched between two silica sheets, and has a flaky form. Talc structure Flaky talcum powder The talc powder is used as a filler to fill the organic polymer material, which can improve the rigidity, dimensional stability and lubricity of the product, prevent high temperature creep, reduce wear on the molding machine, and improve the hardness and creep resistance of the polymer through filling. At the same time, the thermal shock resistance of the polymer can be improved, and the molding shrinkage of the plastic, the flexural modulus of the product, and the tensile yield strength can be improved. Talc powder + carbon black synergy The use of talc in the carbon black reinforcing compound can improve the performance of the rubber compound and improve the quality of the product. The effect of talc + carbon black on the rubber compound is as follows: Rheological properties The addition of talc to the carbon black rubber compound results in a decrease in the viscosity of the rubber compound, thereby improving the fluidity in the mold and reducing the amount of retraction of the extrudate, which is advantageous for improving calendering performance and reducing heat generation. 2. Reinforcement Talc is not just a filler, it is a reinforcing agent. Experiments have shown that the addition of talc to many carbon black elastomeric compounds results in an increase in the elongation at break of the elastomer due to talc. 3. Cut resistance / tear resistance Cutting a tensile specimen with a blade indicates that the talc has greatly improved the toughness and durability of the elastomer. At relatively low elongation (<100%), the carbon black reinforcement sample is completely broken, while the talc reinforcement sample can continue to stretch. Use a blade cut to simulate damage during use 4. Thermal performance Talc can improve heat aging performance. This performance is of great importance for bearing rubber products such as higher temperatures in the hood. 5. Low gas permeability Talc powder can reduce the permeability of carbon black compounds because the flaky form can hinder the diffusion of gases and liquids. It is currently used in tire inner liners to reduce air transmission. 6. Weather resistance Talc reduces the volatilization of the carbon black compound plasticizer, thereby imparting excellent thermal stability and weatherability, thereby extending the life of the product. It limits the migration of by-products to the surface, reduces iridescent blooming and yellowing, and increases the grayscale of automotive window seals. 7. Dispersing aid Talc is a dispersing aid for carbon black reinforced tire tread compounds. It improves the dispersibility of carbon black and other compounding agents and shortens the mixing time by 20%. In order to maintain the abrasion/wear resistance of the rubber compound, the amount of talc powder should be limited to 5 parts. (Powder network editing finishing / orange) Supal(changzhou)Precision Tools Co.,Ltd , https://www.endmillpro.com