Quasi-static mechanical response and corresponding analytical model of laminates incorporating with nanoweb interlayers

Composite nanofibers of multiwalled carbon nanotubes and polyurethane (CNTs-PU) were prepared and collected on the surfaces of T700/epoxy prepregs, acted as nanoweb interlayers, and then formed unidirectional laminates. Quasi-static mechanical responses were examined through tensile and three-point flexure tests to evaluate the reinforcing effect of CNTs-PU nanoweb interlayers on fiber-dominated mechanical properties of the resulting laminates. Results showed that tensile strength and modulus of the laminates integrated with nanowebs increased up to 4.5-8.4% and 3.1-4.7%, respectively. Also, improvements in flexural strength and modulus were correspondingly up to 12.3-15.6% and 0.6-2.7%. Improvement of nanoweb interlayers on fiber-dominated performance of laminates has been achieved successfully. Furthermore, an analytical model based on the modified classical laminated theory and an inverse approach was deduced to investigate the reinforced mechanism. The proposed model could well explain the mechanical responses and the reinforced mechanism of the laminates integrated with nanowebs. (C) 2014 Elsevier Ltd. All rights reserved.