Thermo-viscoelastic properties of silica particulate-reinforced epoxy composites: Considered in terms of the particle packing model

We discuss the effect of compositions of two sizes of silica particles on the thermo-viscoelastic properties of epoxy composites according to Lewis and Nielsen’s mixture law and its particle packing model. Epoxy composites containing varied composition ratios ΦSP of two sizes of spherical silica particles, 0.24 and 1.56 μm, were prepared at a fixed volume fraction (VP = 0.30). The thermo-viscoelastic properties of these composites and neat epoxy resin measured from 123 to 535 K were investigated using Lewis and Nielsen’s law with the maximum packing fraction of particles ϕmax of Ouchiyama and Tanaka’s model. Our results revealed that thermo-viscoelasticity was affected by the maximum packing fraction below the glass transition temperature Tg, and the mobility of matrix resin at T > Tg.