Topic summary
cross-linked
Extracted from the Wikipedia article Cross-link.
Synthetic polymers
In one implementation, unpolymerized or partially polymerized resin is treated with a crosslinking reagent. In vulcanization, sulfur is the cross-linking agent. Its introduction changes rubber to a more rigid, durable material associated with car and bike tires. This process is often called sulfur curing. In most cases, cross-linking is irreversible, and the resulting thermosetting material will degrade or burn if heated, without melting. Chemical covalent cross-links are stable mechanically and thermally. Therefore, cross-linked products like car tires cannot be recycled easily.