Random copolymers of methyl methacrylate and fluorinated polyhedral oligomeric silsesquioxane(F-POSS) were synthesized and the corresponding thin films were prepared from solvent casting.Their microstructure was confirmed by 1H NMR,elemental analysis and GPC.Separation occurs in the bulk of the film during solvent evaporation which can be evidenced by Transmission Electron Microscopy,TEM,with POSS-rich nanophase sizes from 20 to 50 nm.Nanostructuration is attributed to the self-assembly of F-POSS due to the cluster-cluster interactions resulting from the nature of their ligands,i.e.,cycloaliphatic ligands and perfluorinated chains.Thermogravimetric analysis was used to investigate the thermal degradation temperature.It was shown that when F-POSS content is higher than 2.8 mol%,the incorporation of F-POSS could improve the thermal stability of PMMA significantly.In addition,it was shown that these fluorinated POSS-based copolymer surfaces could reduce the surface energy and could be used to design water-repellant nanocomposite coatings.
In this study,platinum(Pt)-polyaniline(PANI)/MWNTs catalysts were synthesized by two sequential reactions.First,coreshell structural PANI/MWNTs composites were fabricated by in-situ chemical oxidation polymerization,in which MWNTs act as the core and PANI as the shell.Then,Pt particles were deposited on the PANI/MWNTs composites by a chemical reduction method.The morphology and constitution of the products were characterized by FT IR,scanning electron microscopy,transmission electron microscopy and XRD.It was observed that the Pt particles were smaller in size and more uniformly distributed on these composite supports than those on the reference,pure MWNT supports.XRD results showed higher Pt(111) content in the catalyst deposited on PANI/MWNTs supports than that on MWNTs.The cyclic voltammeter(CV) tests demonstrated that the electrode modified by Pt-PANI/MWNTs ternary composite catalyst showed a higher catalytic stability than Pt-MWNT binary catalyst did,due to the synergic interaction between Pt and the composite support.
