Multiwalled Carbon Nanotube Reinforced Epoxy Nanocomposites\nfor Vibration Damping

Abstract

Multiwalled\ncarbon nanotubes (CNTs) are used as reinforcement in\nepoxy modified with adduct, that is, block copolymer of carboxyl-terminated\nbutadiene acrylonitrile (CTBN) and diglycidyl ether of bisphenol A\n(DGEBA). Microstructure analysis reveals uniform dispersion of a phase\nwith spherical morphology in a continuous phase. The mean diameter\nof the spherical particles increased with CNT and adduct content.\nAt 30 wt % adduct, adding CNTs results in exceptional growth of spherical\nparticles. Loss factors in the first two modes were determined by\nusing free vibration test in cantilever mode. Significant increase\nin loss factor is obtained for the epoxy nanocomposites modified with\n30 wt % adduct and at all wt % CNTs (i.e., 0.5, 1, and 2.5). The vibration\ndamping mechanism in this nanocomposite is likely due to the relative\nsliding of spherical particles during dynamic loads, which dissipates\nenergy. The reduction in the distance between spherical particles\nas well as the reduction in the elastic modulus of continuous phase\nfacilitate relative sliding.