Molecular dynamics simulation of functional and hybrid epoxy based nanocomposites

Document Type: Research Paper

Authors

1 University of Shahrekord, Mechanical Engineering Department

2 Mechanical Engineering Dept., Shahrekord University

3 Mechanical Engineering Dept., Shahrekord University, Shahrekord, Iran

4 Mechanical Engineering, Khomeinishahr Branch, Islamic Azad University, Isfahan, Iran

10.22075/macs.2020.18878.1226

Abstract

In this paper, the effects of filler type, filler content, functionalization, and the use of hybrid nanofillers on nanocomposite mechanical properties are investigated. For this purpose, several nanocomposite types are modeled and analyzed using Molecular Dynamics method. In addition, crosslinking and nanofiller/matrix interface effects are considered. First thermoset epoxy resin with 75% crosslinking ratio between DGEBA resin and DETA hardener is simulated to determine pure resin properties. Then nanocomposites consisting of single walled carbon nanotubes (SWCNT), nanographene (NG), carbon nanoparticle (CNP), functional single walled carbon nanotubes (SWCNT-COOH), and functional nanographene (nanographene oxide) in thermoset epoxy are modeled and analyzed using Materials Studio software. In addition, filler weight fraction is increased from 2.5 to 10 percent in order to investigate the effects of filler content on nanocomposite mechanical properties. The results indicate that increasing nanofiller weight fraction from 0 to 7.5% results in an increase in nanocomposite elastic modulus for three non-functional nanofiller types. Moreover, functionalization improves nanocomposite properties as the highest increase in resin elastic modulus is obtained for the SWCNT-COOH reinforced epoxy for 7.5 weight percent filler contents. Also, agglomeration occurred at filler contents higher than 7.5 weight percent in the NG/epoxy and SWCNT/epoxy nanocomposites. Finally, the use of hybrid nanofillers reduced/prevented agglomeration for filler contents even up to 10 weight percent.

Keywords