ABSTRACT
Abstract-The surface properties of acrylic UV-cured systems can be modified using small amounts of fluorinated co-monomers, whose performance is strictly dependent on their structure and on the fluorine distribution in the molecule. Different classes of monofunctional fluorinated comonomers were co-polymerised with a typical hydrogenated oligomer via a radical UV-curing process. These include: (meth)acrylates of fluorinated alcohols having the following general structure F-(CF2)m-(CH2)nOH, urethane(meth)acrylates of perfluoropolyether of different molecular weights having the formula CF3CF2O(CF2CF2O)m(CF2O)nCF2CH2O-and urethane(meth)acrylates of perfluoropolypropyleneoxide having different molecular weights and different end groups X (X= Cl or H), whose general structure is XC3F6O-[CF2CF(CF3)O]n-1CF2CH2O-. The main factors controlling the surface activity of the fluorinated co-monomers were studied. With any of the comonomers investigated the surface modification obtained was due to their selective migration to the surface before curing. The curing reaction immobilized the surface structure formed, giving rise to stable properties, independent of the environments to which films were exposed. The surface migration was instantaneous for some co-monomers, while others gave the maximum surface modification after some delay. Factors governing the migration extent and the migration rate are discussed.
