The syntheses of five photochromic monomers derived from N-(2-methacryloxyethyl)-3 0 , 3 0 -dimethylspiro-[2H-1] benzopyrane-2, 2 0 -indoline are reported. The preparation of these compounds involves the heterogeneous reaction between the N-(hydroxyethyl)-2,3,3-trimethylindolenonium bromide and methacryloyl chloride in a polar solvent. The esterificated salt is easily purified by crystallization in chloroform-hexane. Further condensation with the proper 2-hydroxybenzaldehyde produces the photochromic monomer in high yield. This method can also be applied in the preparation of other spiropyrane derivatives.

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Interfacial properties of single-walled carbon nanotubes (SWCNTs) were modified by covalent surface modification of the nanotubes with an ATRP initiator which is able to polymerize acrylic monomers. This methodology starts with the incorporation of 2-phenyl-1-ethanol through a diazotization reaction. Further modification drives to an ATRP initiator, (4-(2-bromo-2-methylpropanoate of 1-hydroxyethyl) phenylidene) which is covalently linked to the surface of the SWCNT. This α-haloester linked to the surface of the SWCNT can be analysed, quantified and used as an initiator in the ATRP polymerization methodology without the addition of the 'sacrificial initiator'. Well control of the molecular weights of the acrylic polymers grown on the surface of SWCNT was obtained. Furthermore, the polymer characterization by FT-IR, NMR CP-MAS, thermo gravimetric analysis and Transmission Microscopy as well as all the intermediates are reported.

The chemical surface modification of graphene and graphene oxide materials is a burgeoning area of investigation. We report the preparation of new ionic forms of graphene oxide by wet chemical modification and metathesis reactions. Graphene oxide (GO) was prepared by a modified Hummers method and functionalized to form cationic and anionic species. The former were prepared via nucleophilic substitution of alkyl amines at the epoxy and hydroxyl groups on the GO while the latter, consisting of sulfonated GO, was prepared via an aryl diazonium salt. The functionalized graphene oxide sheets consist of quaternary ammonium ion substituted GO, GO+, with Cl‐ or I‐ as counter ion and sulfonated GO, GO‐, with H+, Ba2+ or tetraphenylphosphonium (TPP+) ion as counter ions. The addition reaction between GO+ and GO‐ in aqueous solution by metathesis to form a black [GO+][GO‐] precipitate was also investigated. Materials were characterized by XRD, FTIR, Raman, STEM and TEM/HRTEM. Chemically modified graphene and graphene oxides are expected to facilitate further understanding of the chemistry and physics of graphene materials in general and contribute to the formation and further understanding of advanced hybrid graphene and graphene oxide polymer nanocomposites.1,2

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