Influence of the functionalization of carbon nanotubes on calendering dispersion effectiveness in a low viscosity resin for VARIM processes

The use of a three roll machine to disperse nanoreinforcements in polymer matrix has been proved as an alternative to chemical routes of dispersion. Nevertheless, the degree of dispersion achieved depends on the nanoreinforcement type and the sequences used in the calendering process. This research work focuses in the evaluation of the differences in the dispersion effectiveness of functionalized and nonfunctionalized carbon nanotubes (CNTs) in an epoxy resin. This aspect has influence not only on the final properties of the nanocomposites but also on the infiltration process due to changes in the rheological behavior and possible filtering of bigger aggregates. Samples of both types of nanoreinforcements up to percentages of 0.5% in weight were characterized using several techniques before and after the curing stage to evaluate variations in the dispersion of the nanoreinforcement and in the final properties of the two types of nanocomposites. The possibility of using CNT/epoxy mixtures as matrix of multiscale composites has been also evaluated fabricating panels by vacuum assisted resin infusion molding (VARIM). (C) 2012 Elsevier Ltd. All rights reserved.