title: Grafting PMMA Brushes from α-Alumina Nanoparticles via SI-ATRP.
abstract: Alumina nanoparticles are widely used as nanofillers for polymer nanocomposites. Among several different polymorphs of alumina, α-alumina has the most desirable combination of physical properties. Hence, the attachment of polymer chains to α-alumina to enhance compatibility in polymeric matrixes is an important goal. However, the chemical inertness and low concentration of surface hydroxyl groups have rendered polymer modification of α-alumina a long-standing challenge. Herein, we report that activation of α-alumina in concentrated or molten NaOH as well as in molten K2S2O7 increased polymer graft density up to 50%, thereby facilitating the synthesis of α-alumina brush particles with uniform grafting density of 0.05 nm(-2) that are readily miscible or dispersible in organic solvents or in chemically compatible polymeric hosts.
authors.affiliation: Department of Chemistry, Carnegie Mellon University , 4400 Fifth Ave, Pittsburgh, Pennsylvania 15213, United States.
authors.forename: Amir
authors.initials: A
authors.lastname: Khabibullin
authors.affiliation: Department of Chemistry, Carnegie Mellon University , 4400 Fifth Ave, Pittsburgh, Pennsylvania 15213, United States.
authors.forename: Karan
authors.initials: K
authors.lastname: Bhangaonkar
authors.affiliation: Department of Materials Science and Engineering, Carnegie Mellon University , 5000 Forbes Avenue, Pittsburgh, Pennsylvania, 15213, United States.
authors.forename: Clare
authors.initials: C
authors.lastname: Mahoney
authors.affiliation: Department of Materials Science and Engineering, Carnegie Mellon University , 5000 Forbes Avenue, Pittsburgh, Pennsylvania, 15213, United States.
authors.forename: Zhao
authors.initials: Z
authors.lastname: Lu
authors.affiliation: Department of Materials Science and Engineering, Carnegie Mellon University , 5000 Forbes Avenue, Pittsburgh, Pennsylvania, 15213, United States.
authors.forename: Michael
authors.initials: M
authors.lastname: Schmitt
authors.affiliation: National Energy and Technology Lab (NETL), U.S. Department of Energy , 626 Cochrans Mill Rd, Pittsburgh, Pennsylvania 15129, United States.
authors.forename: Ali Kemal
authors.initials: AK
authors.lastname: Sekizkardes
authors.affiliation: Department of Materials Science and Engineering, Carnegie Mellon University , 5000 Forbes Avenue, Pittsburgh, Pennsylvania, 15213, United States.
authors.forename: Michael R
authors.initials: MR
authors.lastname: Bockstaller
authors.affiliation: Department of Chemistry, Carnegie Mellon University , 4400 Fifth Ave, Pittsburgh, Pennsylvania 15213, United States.
authors.forename: Krzysztof
authors.initials: K
authors.lastname: Matyjaszewski
keywords: SI-ATRP; grafting density; hybrid materials; poly(methyl methacrylate); polymer brushes; α-alumina