Prediction and Evaluation of Styrenic Block Copolymers as Surface Modifiers for Multiwalled Carbon Nanotubes in alpha-Terpineol-Based Pastes

Abstract

A well-defined styrenic block copolymer was prepared through controlled/"living" radical polymerization technique and evaluated as a polymeric surface modifier for multiwalled carbon nanotube (MWCNT) in alpha-terpineol-based paste. First, poly(maleic anhydride-co-p-acetoxystyrene)-block-poly(p-acetoxystyrene) copolymer was prepared through a nitroxide-mediated polymerization (NMP) technique in an efficient "one-pot" reaction. The copolymer was then functionalized with pyretic; through an imidization reaction (SPM). Finally, p-acetoxystyrene units were converted to p-hydroxystyrene units through hydrolysis, affording pyrene-functionalized poly(maleic acid-co-p-hydroxystyrene)-block-poly(p-hydroxystyrene) (HSPM). Pyrene units in one block afforded efficient attachment points to the surface of MWCNT through pi-pi interaction, while polyp-hydroxystyrene) or poly(p-acetoxystyrene) tails afforded enhanced affinities With alpha-terpineol, as predicted by Hansen solubility parameter theory. Fabrications of electrodes through screen printing procedures employing MWCNT/HSPM or MWCNT/SPM pastes were facilitated through the surface modification of MWCNTs with the block copolymers, as evidenced by low viscosity, more homogeneous and smooth pastes, homogeneous/uniform MWCNT coatings, and low sheet resistance of the electrode.