The cross‐linking microstructure formed by the metal‐coordination bonds provides excellent properties for rubber materials. Copper sulfate (CuSO4) and tetramethylthiuram monosulfide (TMTM) are successfully compounded with nitrile–butadiene rubber (NBR) to fabricate vulcanizates by the coordination cross‐linking. The curing characteristics, mobility of macromolecular segment, mechanical properties, morphology analysis, swelling properties, and dynamic features under cyclic compression of the vulcanizates are investigated systematically. The results indicate that the microstructure of 3D cross‐linking is held together by the metal‐coordination bonds between Cu2+ and CN. The torque during static vulcanization, tensile strength, and cross‐linking density of the obtained NBR/CuSO4/TMTM vulcanizates are better than that of NBR/CuSO4 vulcanizates, which is attributed to the synergistic effect between the radicals formed by the splitting of TMTM under thermal activation and the Cu2+; moreover, the highly reactive [Cu(SnCNMe2)]•2+ complexes are formed by the synergistic effect and promote the coordination stability of NBR and CuSO4 effectively. The excellent tensile properties of the prepared NBR/CuSO4/TMTM vulcanizates via synergistic effect made the metal‐coordination cross‐linking attractive in the field of industrial application.

The blends of ethylene-acrylic acid copolymer (EAA) and ethylene-vinyl acetate copolymer (EVA) with triple-shape memory effect was fabricated using dicumyl peroxide (DCP) as the crosslinking agent. The mechanical properties and thermal properties were carried out by the universal testing machine and differential scanning calorimetry, respectively. Furthermore, the triple-shape memory behavior of the prepared EAA/EVA blends and EAA/EVA blends crosslinked by DCP were characterized by the shape fixity ratio and shape recovery ratio which were used as the evaluation standards. The blends exhibited the prominent shape memory properties, for example, the first shape fixity ratio was about 90%, the second shape fixity ratio was about 90%, while the first shape recovery ratio was about 100% and the second shape recovery ratio was about 90%. Moreover, the material had a stable shape memory behavior. This novel shape memory polymers expected to have a potential application in smart devices.

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