Preparation and characterization of polybutadiene curing system by click chemistry

Polybutadiene curing systems from propargyl-terminal polybutadiene (PTPB), triazide acetate propane (TAP) and terminal azido polyethylene glycol (APEG) were prepared via the 1,3-dipolar cycloaddition reaction between azido and propargyl groups. By systematically tuning the ratio between TAP and APEG from 0.5 to 6.0, a series of elastomers were prepared and characterized. It was found that at a ratio TAP:APEG of 2.0, the tensile strength of the elastomer is 1.35 MPa, and the elongation at break is as high as 243%. The elongation at break was increased by 835% without the reduction of tensile strength compared to the ones with only TAP as curing agent. In addition, increasing the molecular weight of APEG from 200 g mol⁻¹ to 1000 g mol⁻¹ can improve the mechanical properties of elastomer, and the optimal comprehensive mechanical properties and preparation process were achieved with APEG600.