A novel approach to chemically functionalize multiwalled carbon nanotubes (MWCNTs) for making superior polyetherimide (PEI) nanocomposites with polyfluorene polymer is presented. In this approach, MWCNTs are non-covalently functionalized with poly(9,9-dioctyfluorenyl-2,7-diyl) (PFO) through π-π stacking as confirmed by UV-vis, fluorescence, and Raman spectra. Atomic force microscopy as well as scanning and transmission electron microscopy shows the PFO coated MWCNTs, which provides excellent dispersion of the latter in both solvent and PEI matrix. The strong interaction of PFO with PEI chains, as evidenced from fluorescence spectra, supports the good adhesion of dispersed MWCNTs to PEI leading to stronger interfacial interactions. As a result, the addition of as little as 0.25 wt % of modified MWCNTs to PEI matrix can strongly improve the mechanical properties of the composite (increase of 46% in storage modulus). Increasing the amount of MWCNTs to 2.0 wt % (0.5 wt % PFO loading) affords a great increase of 119% in storage modulus. Furthermore, a sharp decrease of 12 orders of magnitude in volume resistivity of PEI composite is obtained with only 0.5 wt % of PFO modified MWCNT. © 2014 American Chemical Society.
Bibliographical noteKAUST Repository Item: Exported on 2020-10-01
Acknowledgements: This work was supported by King Abdullah University of Science and Technology (KAUST), Saudi Aramco, SABIC Innovative Plastic Co., and King Abdulaziz City of Science and Technology (KACST). The authors are grateful to Dr. Yang Yang and Dr. Liang Li for their assistance in Raman and XRD analysis.
ASJC Scopus subject areas
- Materials Science(all)