Crosslinking of an ethylene-glycidyl methacrylate copolymer with amine click chemistry

Commonly used crosslinking methods for polyethylenes result in the release of harmful by-products. Here, we demonstrate that an epoxy-bearing polyethylene copolymer, which contains 8 wt% glycidyl methacrylate, can be efficiently crosslinked without by-product formation. Click chemistry based on multifunctional amine curing agents, which carry at least two functional groups separated by a flexible spacer, was used to prepare thermosets. Compounding of the crosslinker and copolymer through extrusion at 120 °C could be carried out without onset of the curing reactions. Careful adjustment of the curing time and temperature, ranging from 20 to 120 min and 160–200 °C, resulted in a high network density of at least 2.8 crosslinks per 1000 carbons at a curing agent stoichiometry of as little as 0.5 wt%.