Evaluation of effective properties of piezoelectric hybrid composites containing carbon nanotubes

Abstract

This paper investigates the overall elastic and piezoelectric properties of unidirectional piezoelectric fiber-reinforced polymer composites containing randomly oriented carbon nanotubes (CNTs). To this end, a multi-procedure micromechanics approach based on the Mori-Tanaka model is proposed. In the first step, the elastic properties of a nanocomposite consisting of randomly distributed CNTs in the polymer matrix is modeled. The formation of the interphase region due to non-bonded van der Waals (vdW) interaction between the CNTs and the polymer is taken into account in the micromechanical simulation. In the second step, considering the nanocomposite as a matrix and piezoelectric fiber as reinforcement, the elastic and piezoelectric properties of CNT-piezoelectric fiber-reinforced hybrid composites are predicted. The effects of volume fractions of CNT and piezoelectric fiber, and CNT diameter, thickness and adhesion exponent of the interphase on the hybrid composite elastic and piezoelectric coefficients are examined. The results clearly highlight the benefits of CNTs into the conventional piezoelectric composites from a structural point of view. The overall electro-mechanical properties of the piezoelectric fiber-reinforced polymer composites can be significantly enhanced with adding CNTs. It is found that the interphase region can play a crucial role in the effective properties of the piezoelectric hybrid composites. © 2018 Elsevier Ltd