A Room Temperature Curing Agent for Hydroxyl-Terminated Polybutadiene: Synthesis of a Novel Nitrile N-Oxide and Curing Properties of the Polymer Network

Abstract 2,5-Diethyl-1,4-benzenedinitrile N -oxide was designed and synthesized to achieve room temperature curing of hydroxyl-terminated polybutadiene binders. The structures and properties of the four cured elastomers having different content of curing agent were investigated. The results showed that the isoxazoline rings from the reaction of nitrile N -oxide with cis -alkene are observed in the four cured elastomers. The results also revealed that the hydroxyl-terminated polybutadiene with the lowest content of curing agent showed the lowest cross-linking density and stress at break. The proper activity and steric hindrance of 2,5‑diethyl-1,4-benzenedinitrile N -oxide gave better mechanical properties and hydrophobic properties of the cured elastomers than nitrile N -oxide prepared by our previous work.