Synthesis and Properties of a Polyfluorinated Prepolymer Multifunctional Urethane Methacrylate

Abstract

A significant factor affecting the durability of current resin based dental composite restoratives is the susceptibility of their polymeric matrices and interfacial phases to plasticization and degradation induced by the constant exposure to the oral environment. The concept of using low surface energy resin binders, having solubility parameters far different from that of oral fluids, as a means of enhancing the intra-oral resistance of resin based dental materials led to the synthesis of a unique polyfluorinated prepolymer multifunctional methacrylate, [PFMA], which yields extremely hydrophobic composites of moderate strength. This study describes the synthesis and properties of an analogous polyfluorinated prepolymer multifunctional urethane methacrylate, [PFUMA], which is also a low surface energy resin but with greater cohesive energy density than [PFMA]. [PFUMA] was isolated in excellent yield from the reaction of 2-isocyanatoethylmethacrylate [IEM] and the same polyfluorinated prepolymer polyol, [PFP], used in the synthesis of [PFMA]. This synthetic method is general and offers a facile means of converting other polyols and similar compounds with active hydrogens to methacrylate derivatives. Preliminary results indicate that composites based on [PFUMA] are stronger and almost as hydrophobic as those derived from [PFMA].