What category does a cross linker belong to in the context of polymer chemistry?

A cross linker is best categorized as a cross-bridging agent in the context of polymer chemistry. Cross linkers are substances that create connections between polymer chains, leading to the formation of a three-dimensional network. This networking enhances the properties of the polymer, such as increasing its mechanical strength or improving its resistance to solvents.

The role of cross linkers is essential in various applications, including the production of durable coatings, adhesives, and elastomers. By facilitating the bond formation between separate polymer chains, cross linkers significantly alter the material's overall characteristics, which is why they are specifically referred to as cross-bridging agents.

In contrast, other categories like adhesives are materials used to bond surfaces together, while monomers are the basic building blocks that undergo polymerization to form polymers. Resins are broad categories that include various types of polymers, but they do not specifically define the role that cross linkers play in enhancing polymer properties through cross-linking. Thus, recognizing cross linkers as cross-bridging agents aligns them more accurately with their primary function in polymer chemistry.