Electrical and Mechanical behaviors of rubber composites based on polar elastomers with incorporated Cu-based alloy

Abstract Dielectric elastomers (DE) containing conducting inorganic fillers would have great potential for actuators, capacitive energy storage, elastomer sensors and many other applications. In this regard, ternary composites with metal alloy materials as reinforcing fillers might be an enabler for low dielectric loss and high dielectric constant. Herein, ternary rubber composites were prepared by incorporation of Cu-based alloy into acrylonitrile-butadiene rubbers (NBR). However, material incompatibility between the Cu-Al-Zn alloy and the rubber matrix often results in phase separation, void formation and particle aggregation, with dramatically degraded performance. Through surface modification, Cu-Al-Zn alloy particles were uniformly dispersed onto the NBR rubber matrix via 3-(Trimethoxysilyl) propyl methacrylate (TMSPM) as coupling agent. The effective reinforcement of modified Cu-based alloy particles into NBR was systematically analyzed by SEM (scanning electron microscope) and XRD (X-ray diffraction). The results reveal that the morphology and dispersion state of modified Cu-Al-Zn alloy were critical to the dielectric properties of the NBR compounds. Mechanical properties were greatly enhanced by the reinforcement of modified Cu-based alloy into the NBR matrix. The outstanding performance of NBR composites is due to the uniform dispersion of modified Cu-Al-Zn alloy particles and good interfacial compatibility with rubber matrix, suggesting high performance dielectric composite.