Photopolymerization of ternary thiol-ene/acrylate systems:: Film and network properties

Photocurable, ternary-component mixtures of a 1:1 molar multifunctional thiol-ene (trithiol and triallyl ether) blend and a 16-functional acrylate based monomer have been photopolymerized, and the final film properties of the ternary crosslinked networks have been measured. The photopolymerization kinetics, morphology, and mechanical and physical properties of the films have been investigated with realtime infrared, atomic force microscopy, and dynamic mechanical analysis. The photopolymerization process is a combination of acrylate homopolymerization and copolymerizations of thiol with allyl ether and acrylate functionalities. The tan delta peaks of the photopolymerized ternary systems are relatively narrow and tunable over a large temperature range. The morphology is characterized by a distinct phase-separated nanostructure. The photocured thiol-ene/acrylate ternary systems can be made to exhibit good mechanical properties with enhanced energy absorption at room temperature by the appropriate selection of each component concentration. (c) 2007 Wiley Periodicals, Inc.