Natural rubber has good elasticity, high mechanical energy, and excellent processing performance, making it the earliest and most widely used rubber in the rubber product industry. However, the price of natural rubber is high and fluctuates greatly, resulting in great cost pressure on manufacturers; Many rubber product manufacturers using natural rubber as their main raw material have begun to use recycled rubber. When producing rubber products with natural rubber/recycled rubber blends, the design of the reinforcement and filling system directly affects the physical and mechanical properties and service life of the rubber products.
1. Key points for design of reinforcing and filling system for black rubber products produced from natural rubber/recycled rubber
When using natural rubber/recycled rubber to produce black and dark rubber products, the reasonable use of carbon black can further improve the wear resistance and tear resistance of the compound. When natural rubber/recycled rubber products require high wear resistance, ultra-wear carbon black (N110), medium and ultra-wear carbon black (N220), and high wear carbon black (N330) can be used; When there is a high requirement for the tear resistance of the rubber compound, it is recommended to use the trough method carbon black or the modified furnace method carbon black; For those with low requirements for strength and strict requirements for elasticity and processability, quick press furnace black (N550), universal furnace black (N660), and semi reinforced carbon black (N770) can be used.
When selecting reinforcing carbon black for black natural rubber/recycled rubber products, it is necessary to fully consider the particle size, structure, surface activity, pH value, and other indicators of carbon black. Small particle size, large specific surface area, high strength (tensile strength, tear strength, wear resistance) of the filled rubber, but great hardening effect, poor elasticity, processing ability, and poor fluidity; High structure (high oil absorption value), high rubber hardness and constant elongation stress; PH value affects the curing rate, so the variety and dosage of the curing system should be adjusted accordingly based on the acid and alkali properties of carbon black. For furnace process carbon black compounds, aftereffect promoters (CZ, NOBS, etc.) should be selected, and the dosage should not be too large.
2. Key points for design of reinforcement and filling system for light colored rubber products produced from natural rubber/recycled rubber
Natural rubber is often used in combination with light colored latex reclaimed rubber, such as white latex reclaimed rubber, to produce light colored and colored rubber products; At this time, it is recommended to use white carbon black, ultra-fine activated calcium carbonate, etc. as reinforcing filler (reinforcing agent). When using white carbon black 2SLYY330, organic active agents such as diethylene glycol (DEG), glycerol, triethanolamine (TEA), polyethylene glycol (PEG), etc. with a content of 5% to 10% of white carbon black, should be added to adjust the sulfurization rate.
When designing a reinforcing and filling system for natural rubber/reclaimed rubber products, the amount of rubber reinforcing agent and filler should be determined based on the product's performance requirements and rubber content index. Generally, when the strength requirement is high, the amount of reinforcing agent can be increased to 40-50 parts; Low strength and low cost are required. It is recommended to add a large amount of fillers such as clay, clay, light calcium, and rubber powder. The amount of filler can be increased to 200 parts or more to reduce the rubber content. Later, the editor will continue to share with you the design points of the vulcanization system, softening system, and aging prevention system for natural rubber/recycled rubber production rubber products.
Exclusive original article [commercial authorization] reprint, excerpt and excerpt in any form are prohibited without written authorization. Focus on Hongyun rubber: learn the process formula and raw material technology of producing rubber products from recycled rubber to help you reduce costs and increase profits