The green strength of EPDM rubber is between 2-7MPa, and the pure rubber formula used directly in the production of rubber products simply cannot meet the rubber product's demand for rubber compound tensile strength. In general, the tensile strength of EPDM vulcanizate can reach 10-25MPa after using carbon black to reasonably reinforce and fill. In actual production, because the excessive amount of reinforcing agent and filler will affect other indicators of EPDM rubber products, rubber product manufacturers will further improve the tensile strength of rubber compounds through other methods to meet demand.
1. Increasing the tensile strength of EPDM compound requires the rational use of carbon black
Carbon black is the most commonly used reinforcing agent in the production of EPDM rubber products. The rational use of carbon black can significantly improve the tensile strength of rubber products. Tests show that the tensile strength of EPDM compound will continue to increase as the amount of carbon black increases, and will remain unchanged after reaching a certain peak. When using carbon black to improve the tensile strength of EPDM compound, rubber product manufacturers need to combine the effect of carbon black on other indicators of the compound to reasonably control the amount of carbon black.
2. Use polypropylene to improve the tensile strength of EPDM compound
Polypropylene is a polymer formed by the addition polymerization of propylene. It is colorless, odorless, non-toxic, translucent, and has high toughness and high wear resistance. Using a certain proportion of polypropylene in EPDM compound can significantly improve the tensile strength and wear resistance of EPDM vulcanizate. In practical applications, EPDM rubber can also be used to improve the low temperature toughness and impact strength of PP materials.
3. Use sulfur-vulcanized EPDM vulcanizate for higher tensile strength
There are three common vulcanization systems for EPDM rubber products: sulfur vulcanization, peroxide vulcanization and resin vulcanization. The sulfur crosslinking network after sulfur is dominated by polysulfide bonds, and the tensile strength of vulcanized rubber is better. If you want to improve the heat resistance, aging resistance and compression permanent deformation resistance of EPDM rubber, rubber product manufacturers choose peroxide 2LLYY54 to add a small amount of sulfur during vulcanization to form a peroxide-sulfur vulcanization system to further improve The tensile strength of EPDM compound.
At present, many rubber product manufacturers will choose EPDM rubber + EPDM reclaimed rubber combined use method to produce EPDM rubber products, to improve the tensile strength of EPDM / recycled rubber combined rubber, rubber product manufacturers need not only consider supplement The dosage of strong agent, reinforced materials, types of vulcanization system, etc., also need to consider the mechanical indexes of reclaimed rubber, adjust the formula appropriately, and further improve the tensile strength of EPDM vulcanizate.