The price of reclaimed rubber is much lower than that of raw rubber, and the price of many high-performance carbon black is higher than that of reclaimed rubber itself. The main purpose of using carbon black in reclaimed rubber products is not to reduce the cost, but to cover up the "short board" with slightly lower mechanical strength of reclaimed rubber itself and further improve the technological properties of reclaimed rubber. Hard carbon black in carbon black products can obviously improve the mechanical strength of reclaimed rubber vulcanizates, such as high wear-resistant carbon black, medium and super wear-resistant carbon black, so what specific effects does the use of such carbon black have in the production of reclaimed rubber products?
High abrasion resistance furnace black: The most commonly used hard reinforced carbon black in the production of recycled rubber products can obviously improve the hardness, elongation stress, abrasion resistance, compression permanent deformation resistance and aging resistance of the vulcanizate. High wear-resistant furnace black is easy to disperse uniformly in regenerated rubber, the surface of extruded rubber is smooth and bright, and the heat generated in the production process is very low. It should be noted that the high wear-resistant furnace black can significantly improve the hardness of the vulcanizate, lead to the deterioration of elasticity, elongation at break and tear strength. It is usually necessary to coordinate the relationship between the various indicators of the recycled rubber products with other types of carbon black or rubber oil.
High wear resistance furnace black can be divided into high structure product and low structure product according to its structure degree. The reinforcing effect of medium and low structure product in regenerated rubber is similar to that of natural gas tank black, which can improve the elongation at break, tear strength and dynamic performance of regenerated rubber vulcanizate. Generally, the higher the structure of carbon black, the better the reinforcing effect in the recycled rubber, the higher the wear resistance of the recycled rubber vulcanizate, and the worse the wear resistance of the recycled rubber vulcanizate derived from the low structure of high wear resistance furnace black.
Medium ultra-abrasion-resistant carbon black: high structure carbon black, small particle size, second only to ultra-abrasion-resistant carbon black, in the production of recycled rubber products can not only improve the processing properties of rubber, but also significantly improve the tensile strength, elongation stress, tear strength, abrasion resistance and piercing resistance of recycled rubber vulcanizate, especially suitable for tire tread rubber. Medium and super wear-resistant carbon black also has high structure products and low structure products. High structure products are more beneficial to the processing technology and wear resistance of recycled rubber vulcanizates. Low structure medium and super wear-resistant carbon black can significantly improve the tear resistance and flexural cracking resistance of rubber compounds.
When using recycled rubber to produce rubber products, wear-resistant hard carbon black and ultra-wear-resistant carbon black are basically the same as high-wear furnace black and medium-ultra-wear-resistant carbon black, and the usage method is not elaborated in this subchapter. Recycled rubber products in the production process will also use some carbon black to fill the rubber, such as spray carbon black, hot cracking carbon black, etc., Xiaobian will continue to share with you the role of other carbon black in reclaimed rubber and application skills.