UV-curable systems containing perfluoropolyether structures: Synthesis and characterisation

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.