Harnessing Ni–PDC Coordination Chemistry to Achieve Robust Performance in Peroxide‐Cured HNBR Elastomers

This study investigates the effect of a nickel complex of 2,6‐pyridinedicarboxylic acid (Ni‐PDC) in modulating the properties of hydrogenated nitrile butadiene rubber (HNBR) composites. The composites were prepared via dicumyl peroxide (DCP) crosslinking, with varying Ni‐PDC loadings. Structural analyses via Fourier transform infrared spectroscopy (FTIR) and X‐ray diffraction (XRD) confirm successful integration of the Ni–PDC complex into the HNBR matrix. However, X‐ray photoelectron spectroscopy (XPS) supports the presence of Ni 2+ and validates Ni‐PDC coordination within the HNBR matrix. Curing studies reveal a reduction in viscosity and an alternative in crosslink density. Mechanical testing reveals appreciable reinforcement, with a significant enhancement in tensile strength and elongation at break in comparison with unreinforced HNBR. Furthermore, the conduction of cyclic stress–strain study demonstrates a reduction in hysteresis losses, thereby signifying an enhancement in elastic recovery. Thermogravimetric analysis (TGA) reveals increased thermal stability, while differential scanning calorimetry (DSC) indicates a downward shift in glass transition temperature, consistent with enhanced segmental mobility imparted by dynamic coordination of Ni–PDC complex. The present study reports the combined effect of DCP curing and Ni‐PDC incorporation in HNBR composites, with a view to enhancing their mechanical performance, flexibility (viscoelasticity) and thermal resistance.