title: Surface Modification of Multiwalled Carbon Nanotubes with Cationic Conjugated Polyelectrolytes: Fundamental Interactions and Intercalation into Conductive Poly(methyl methacrylate) Composites.
abstract: This research investigates the modification and dispersion and of pristine multiwalled carbon nanotubes (MWCNTs) through a simple solution mixing technique based on noncovalent interactions between poly(phenylene ethynylene)-based conjugated polyelectrolytes functionalized with cationic imidazolium solubilizing groups (PIM-2 and PIM-4) and MWCNTs. Spectroscopic studies demonstrated the ability of PIMs to strongly interact with and efficiently disperse MWCNTs in different solvents, mainly due to π interactions between the PIMs and the MWCNTs. Transmission electron microscopy and atomic force microscopy revealed the coating of the polyelectrolytes on the walls of the nanotubes. Scanning electron microscopy (SEM) studies confirm the homogeneous dispersion of PIM-modified MWCNTs in the poly(methyl methacrylate) (PMMA) matrix. The addition of 1 wt % PIM-modified MWCNTs to the matrix has led to a significant decrease in DC resistivity of the composite (13 orders of magnitude). The increase in electrical conductivity and the improvement in the thermal and mechanical properties of the membranes containing the PIM-modified MWCNTs is ascribed to the formation of MWCNT networks and cross-linking sites that provided channels for the electrons to move in throughout the matrix and reinforced the interface between MWCNTs and PMMA.
authors.affiliation: †Smart Hybrid Materials (SHMs) Lab, Advanced Membranes and Porous Materials (AMPM) Center, King Abdullah University of Science and Technology (KAUST), Thuwal 23955-6900, Kingdom of Saudi Arabia.
authors.forename: Alaa
authors.initials: A
authors.lastname: Ezzeddine
authors.affiliation: †Smart Hybrid Materials (SHMs) Lab, Advanced Membranes and Porous Materials (AMPM) Center, King Abdullah University of Science and Technology (KAUST), Thuwal 23955-6900, Kingdom of Saudi Arabia.|‡ Department of Chemistry and Center for Macromolecular Science and Engineering, University of Florida, P.O. Box 117200, Gainesville, Florida 32611-7200, United States.
authors.forename: Zhuo
authors.initials: Z
authors.lastname: Chen
authors.affiliation: ‡ Department of Chemistry and Center for Macromolecular Science and Engineering, University of Florida, P.O. Box 117200, Gainesville, Florida 32611-7200, United States.
authors.forename: Kirk S
authors.initials: KS
authors.lastname: Schanze
authors.affiliation: †Smart Hybrid Materials (SHMs) Lab, Advanced Membranes and Porous Materials (AMPM) Center, King Abdullah University of Science and Technology (KAUST), Thuwal 23955-6900, Kingdom of Saudi Arabia.
authors.forename: Niveen M
authors.initials: NM
authors.lastname: Khashab
keywords: CPEs; MWCNTs; PMMA; composites; conjugated polyelectrolytes; dispersion; electrical conductivity; multiwalled carbon nanotubes; poly(methyl methacrylate)