The synthesis of new functionalised macromers containing perfluoropolyether structures (PFPE) is reported. They are obtained by reaction of bis‐CH2OH terminated PFPE with isocyanato‐ethyl methacrylate (EIM), giving rise to the formation of perfluoropolyether bisurethane methacrylate (PFEUMA) oligomers. The products are characterised by NMR and FTIR analyses. The thermal behaviour reveals two amorphous phases, corresponding to the fluorinated and the hydrogenated moieties, while a crystalline phase can be present depending on the macromer structure. The functionalised macromers are UV‐cured in the presence of a photoinitiator and the complete disappearance of the double bonds is obtained. The cured films are characterised by differential scanning calorimetry (DSC) and dynamic mechanical thermal analysis (DMTA) confirming the presence of a multiphasic structure. Moreover the optical properties and the surface properties of the cured systems are investigated and discussed.

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Two commercially available epoxy-fluorinated monomers, 3-(perfluorooctyl)-1,2-propenoxide and 3-(1H, 1H, 9H-hexadecafluorononyloxyl)-1,2 propenoxide, were used as modifying additives for UV curable systems. These two fluorinated monomers were mixed, in small amounts (less than 1% w/w) with a hydrogenated epoxy monomer 1,4-cyclohexanedimethanol-diglycidyl ether. The mixtures were coated on glass substrate and UV-cured, giving rise to transparent films. Notwithstanding their very low concentrations, the fluorinated monomers caused a change in the surface properties of the films, without changing their curing conditions and their bulk properties. The air side of the coatings became highly hydrophobic, while the substrate side was unmodified. As shown by XPS measurements, the fluorinated monomers were able to concentrate selectively on the air side of the films, forming a fluorinated layer.

A series of fluorinated acrylates [F(CF 2 ) q O(CH 2 ) p OOCOCHACH 2 , where q ϭ 8 and p ϭ 2 Ϭ 11) were synthesized and used as comonomers in the photopolymerization of acrylic systems. These fluoroacrylates were synthesized in a three-step procedure through the radical addition of perfluoroalkyliodides to an unsaturated alcohol followed by their acrylation. The mixtures, containing up to 0.8% (w/w) of the comonomers, produced transparent films after UV curing; they showed changes in the surface properties as a function of the comonomer type and concentration. With contactangle and X-ray photoelectron spectroscopy analyses, the relationship between the structure of the monomers and the surface properties of the UV-cured films was investigated: the wettability decreased, depending on the length of the fluorinated group (q value) and the hydrogenated segment of the monomer (p value).

Polystyrene/montmorillonite nanocomposites were prepared via in situ bulk polymerization. New imidazolium salts were used to modify montmorillonite obtaining an improvement in thermal stability in comparison with a montmorillonite modified with a standard alkylammonium cation. The synthesized cations facilitate the formation of partially exfoliated structures because of the presence in their structure of a polymerizable group. The polystyrene/montmorillonite nanocomposites were characterized by X‐ray diffraction, thermogravimetric analysis, scanning electron microscopy (SEM), and transmission electron microscopy (TEM).The new thermally stable, reactive surfactant imidazolium salts (C12, C16 and C18) used to organically modify montmorillonite in this study.magnified imageThe new thermally stable, reactive surfactant imidazolium salts (C12, C16 and C18) used to organically modify montmorillonite in this study.

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