Rheometeric, ultrasonic and acoustical shielding properties of Cu-alloy/silicone rubber composites for electronic applications

Abstract

Silicone rubber (SR) is a highly adaptable material that is attractive for a variety of applications, including electronics, construction, and aerospace. In general, adding Cu-Al-Zn alloy to the SR matrix improved the mechanical properties of rubber composites and noise attenuation. The mechanical, magnetic, ultrasonic, and acoustic characteristics of the resulting SR-composites were characterized. According to variations in treated Cu-alloy loading, ultrasonic measurements were performed as the ultrasonic velocities, Poisson’s ratio, Young’s modulus, acoustic impedance, ultrasonic attenuation coefficient, and micro-hardness. Results indicated that adding treated Cu-alloy to SR-composites improves them significantly. They showed that curing time decreases gradually, tensile strength increases constantly and elongation at break of SR-composites has maximum value at 15% treated Cu-alloy. The coupling agent 3-(Trimethoxysilyl) propyl methacrylate (TMSPM) improves the mechanical properties of the composites by forming a network structure in the SR matrix and enhancing the interfacial interaction between the Cu-alloy and the SR matrix. The acoustic sound absorption coefficient, reflection coefficient, and damping factor calculations were studied in addition to the decibel drop ranging from 0.4–4.9 dB. The composite sample SR-4 is considered to have the optimal percentage of the selected acoustic properties studied. Thus, the shielding efficiency of SR-composite increased with increasing content of Cu-alloy which makes it applicable in ear plugs and electronic applications.