Heterogeneous Transport Processes and Unexpected Structure Formation in Layered Epoxy and Epoxy-Alumina Nanocomposite Systems

Static and dynamic hypersonic properties are probed to reveal the subtle interplay between demixing, matter transport, chemical network formation, polymer network swelling, and network damage in the vicinity of the interface between the reactants of amine-curing epoxies. An innovative time- and space-resolved acoustic microscopy, called scanning Brillouin microscopy, gives access to these competing transport and structure formation processes in epoxy systems consisting of either pure resin, alumina nanoparticles-filled resin, or various epoxy resin-hardener mixtures topped by a layer of pure hardener. Static and dynamic hypersonic properties are probed to reveal the subtle interplay between demixing, matter transport, chemical network formation, polymer network swelling, and network damage in the vicinity of the interface between the reactants of amine-curing epoxies. An innovative time- and space-resolved acoustic microscopy, called scanning Brillouin microscopy, gives access to these competing transport and structure formation processes in epoxy systems consisting of either pure resin, alumina nanoparticles-filled resin, or various epoxy resin-hardener mixtures topped by a layer of pure hardener

Combination of high performance refractometry and infrared spectroscopy as a probe for chemically induced gelation and vitrification of epoxies

A combination of infrared spectroscopy and high performance refractometry was used to investigate the chemically induced sol-gel and glass transition during the polymerization of epoxies. Representations of the refractive index versus chemical conversion reveal an interesting insight in the optical properties accompanying gelation and vitrification. Whereas the electronic polarizability of the liquid state of small average molecular mass and the glassy state is dominated by the mass density, an unexpected excess polarizability observed during the gelation is attributed to cooperative dipole-dipole interactions