What are the functions of crosslinking agents

Some people may ask what crosslinking agent is? Crosslinking agent is a type of additive that releases free radicals upon heating to activate polymer chains, causing them to undergo chemical reactions and crosslink with each other. Professionals tell us that when using crosslinking agents, we should try to avoid adding acidic fillers as much as possible, and be cautious when adding antioxidants. Other aromatic hydrocarbon oil additives can have a negative impact on the crosslinking effect, so we must pay attention to this.

Crosslinking agents are often substances containing multiple active functional groups, such as dicarboxylic acids, polyacids, diamines, polyisocyanates, or compounds containing multiple unsaturated double bonds, as well as sulfur, organic peroxides, metal oxides, etc. Organic peroxides are commonly used as crosslinking agents for vinyl resins, unsaturated polyesters, ethylene propylene rubber, silicone rubber, fluororubber, and polyurethane rubber.

Crosslinking agents play a significant role in the modification of adhesives, improving bonding strength, heat resistance, water resistance, chemical resistance, creep resistance, aging resistance, and more. The mechanisms of action of various crosslinking agents are different, some of which react directly with the active groups of polymer macromolecules to produce crosslinking. Some are copolymerized with monomers into linear macromolecular chains, and then crosslinked between molecules under the action of heat, oxygen, radiation, etc. Therefore, for different types of adhesives, appropriate crosslinking agents should be selected to achieve good crosslinking effects.