UV light-induced grafting of fluorinated monomer onto cellulose sheets

The surface modification of cellulose opens the way towards almost infinite new applications, making it suitable for functional and sustainable materials. Additionally, it also represents a possibility for up-grading traditional products. In this work, we report about the photo-induced grafting onto cellulose substrates of a highly fluorinated acrylic monomer, characterized by a long perfluoropolyether chain. Grafting changed the surface composition, as assessed by XPS measurements: the values of F/C atomic ratio were close to that of the pure monomer at the most external surface (~13 Å depth). Surface energy was therefore dramatically reduced. This led to interesting modifications of the paper characteristics. The wettability by different liquids was decreased and the stain resistance improved. Moreover, anti-adhesion properties were imparted to the paper sheet. At the same time the bulk properties of the modified fibre network, such as its tensile strength and the burst resistance, were unchanged.