Efficient dispersion of carbon nanotubes in polyvinylbutyral and mechanical performance of composites thereof

In this work polyvinyl butyral (PVB) was used both as a dispersing agent for carbon nanotubes (CNTs) into ethanol, and as the matrix for composite tapes obtained by the tape casting technology. Heavily entangled commercial CNTs were used, in order to verify the effective polymer dispersing capability and the methodology. The dispersing effect of PVB is probably due to a polymer wrapping effect, and is evident also at low concentration, even if some bundles of CNTs can remain in the suspension. A slurry of PVB containing various percentages of carbon nanotubes was tape cast to obtain composite tapes, whose mechanical properties depends on both the concentration of CNTs and the type of PVB. If the CNTs concentration is too high, undispersed bundles remain, that reduce mechanical properties. If the PVB chain is too short, no significant mechanical properties improvement is observed.