Study on the relationship between structure and acoustic performance of NBR composite materials

Abstract

Rubber materials have been widely used in the field of noise absorption and vibration reduction due to the unique viscoelasticity. Among all the rubbers, nitrile-butadiene rubber (NBR) has strong polarity and excellent damping properties as a result of –CN groups, so it is often chosen as a matrix of damping materials. However, the effects of chemical structures and fillers on the damping and sound absorption properties of rubber materials have not been fully investigated. To achieve a high loss factor at room temperature, NBR materials with different acrylonitrile contents and crosslinking densities were investigated. The results showed that the changes in crosslink density and acrylonitrile content have limited improvements in damping and sound absorption properties. In order to improve the sound absorption performance of NBR, different kinds of fillers were introduced into rubber matrix. It is proved that poor interfacial interactions between fillers and rubber dissipated more sound waves. This work would provide further insights into the design of materials with good sound absorption performance. • Increasing Acrylonitrile Content Improves Acoustic Performance. • Lower crosslink density can improve sound absorption. • Weak interaction between filler and matrix is benefit to sound absorption.