The influence of carbon black particle size and structure on the index of recycled rubber
Carbon black is an important reinforcing filler in the production of recycled rubber products. Adding carbon black in moderation can improve the tear resistance and flexion resistance of recycled rubber products and improve the processing technology of products.The type, particle size, activity, structure, dosage, etc. of carbon black will affect the reinforcing effect of carbon black in recycled rubber products. For example, the particle size of carbon black is directly related to the tensile strength, tear strength, wear resistance, elasticity, etc. of recycled rubber products; The structure directly affects the expansion rate of recycled rubber.
Under normal circumstances, the smaller the particle size of carbon black, the greater its surface activity, the higher its structure, and the higher its tensile strength; the tensile strength of recycled rubber products will increase first and then decrease as the amount of carbon black increases, and there is a peak in the middle; under the premise that other conditions permit, try to choose high-fineness carbon black as the reinforcing filler in recycled rubber products, which significantly improves the tensile strength of recycled rubber products.Compared with the degree of structure, the particle size of carbon black has relatively little effect on the compression expansion rate of recycled rubber; in the case of the same degree of structure, carbon black with small particle size and large activity has a greater impact on the compression performance of recycled rubber than carbon black with small activity.
Under normal circumstances, carbon black aggregates with high structure have high porosity and form more absorbent rubber, thereby reducing the volume fraction of free rubber in the system; therefore, the carbon black used in the pressed rubber 2ELYY119YC has a high structure and a small expansion rate.In addition, the smaller the particle size of carbon black, the higher the tear strength of recycled rubber; when the particle size of carbon black is the same, the lower the structure and the higher the tear strength for crystalline rubber, the higher the tear strength of carbon black with high structure for amorphous rubber; the tear strength of recycled rubber will increase first and then decrease as the amount of carbon black increases.
The amount of carbon black in the recycled rubber should not be lower than a certain amount.For example, the amount of carbon black in butyl reclaimed rubber or butyl rubber/reclaimed rubber combined rubber is recommended to be controlled at more than 40 parts by mass, or the amount of inorganic fillers is more than 60 parts by mass.