VISCOELASTIC DAMPING PERFORMANCE AND RHEOLOGICAL BEHAVIOUR OF CUP STACKED CARBON NANOTUBE MODIFIED EPOXY NANOCOMPOSITES WITH RE AGGLOMERATION NETWORK

For over a decade, carbon based nanotubes have been considered as nano scaled fillers for potential reinforcement for polymers due to their exceptional mechanical properties. Re-agglomeration is a natural phenomenon in which the initially dispersed carbon nanotubes (CNTs) have the natural tendency to form a secondary agglomeration network during the subsequent curing process. Its morphological characteristics can vary for different filler content, processing time and temperature, thus influencing the physical and mechanical properties of cured nanocomposites. This work describes how to tailor the morphology of such re-agglomerations of cup-stacked carbon nanotube (CSNT) in an aerospace grade RTM6 epoxy. Loss and storage modulus of cured sample and the rheological behavior of uncured suspensions under amplitude sweep within the linear viscoelastic range were examined to identify the effects of the presence of a hierarchical filler network. Manufacturing parameters like the filler content, the melt temperature and the curing time have been studied. The results indicate that a controlled secondary re-agglomeration network may provide superior mechanical and viscoelastic properties in cured nanocomposites.