Trace electrosprayed nanopolystyrene facilitated dispersion of multiwalled carbon nanotubes: Simultaneously strengthening and toughening epoxy

The search of multifunctional epoxy nanocomposites with both strength and toughness combined with smart features such as electrical conductivity is essential in design of advanced materials. In this work, by utilizing a binary nanofiller strategy, both strength and toughness as well as high electrical conductivity are obtained in epoxy with trace nanopolystyrene grafted with epichlorohydrin (nano g-PS) to facilitate the dispersion of multi-walled carbon nanotubes (MWCNTs). The increased tensile strength (37.6%) and flexural strength (34.4%) are acquired in nano g-PS (0.0677 vol%)/MWCNTs (0.0335 vol%)/epoxy in contrast to pure epoxy. A remarkably improved tensile toughness up to 379.2% and an increased elongation at break up to 208.3% are obtained in this epoxy nanohybrid. The synergistic interactions among nano g-PS, MWCNTs and epoxy matrix as well as the state transition of nano g-PS from glassy state to fluid state provide an improved dispersion of nanofillers which is responsible for the increased electrical conductivity and enhanced mechanical properties. The decreased surface resistivity allows these nanohybrids to sufficiently dissipate surface charges as an antistatic material. This work provides an effective way to disperse carbon nanotubes with small amount of thermoplastic PS to simultaneously strengthen and toughen the thermosetting epoxy while introducing highly conductive function. (C) 2018 Elsevier Ltd. All rights reserved.