抄録
The dynamic viscoelastic properties of epoxy resin reinforced with short Kevlar fiber in randomplanar orientation were studied above room temperature. The composite reinforced with short E glass fiber in random-planar orientation was also studied for comparison purpose. Above the primary dispersion (α) temperature for the Kavlar reinforced composite, three additional dispersions (α′, α″ and α_??_) are separately observed in the log E″ vs. reciprocal absolute temperature curve. On the other hand, two additional dispersions (α′ and α″) are observed above the α dispersion temperature for the E glass fiber reinforced composite. The α″ and α_??_ dispersions of the Kevlar composite are considered to correspond to the α′ and α″ dispersions of E glass fiber composite, respectively, for which the relaxation mechanisms are deduced in a previous paper4) The α′ dispersion of the Kevlar composite is considered to originate from the friction or slippage among the microfibrils of Kevlar fiber which are formed by the fibrillation or splitting of the fiber surface during the measurement of the dynamic viscoelastic properties.
