Nanofilled polyethylene terephthalate fibers for the production of hierarchical polymer based composites

The potential improvement of physical and mechanical properties in nanostructured composites can be fully exploited by proper distribution of the nanofillers in the polymer matrix, which strongly affects both their final properties and processability. A nanofilled thermosetting polymer can be used as a matrix for continuous fibers when the alignment of a high aspect ratio nanofiller is achieved: in this case a hierarchical composite is obtained. In this work a new processing technology for the production of hierarchical polymer based composites is proposed. First, the alignment of graphene nanoplatelets (GNPs) in thermoplastic fibers of amorphous polyetylene terephthalate (PETg) is achieved by a fiber spinning process. The obtained nanocomposite fibers with a very high filler content (10 wt%) are then transferred into a reactive epoxy resin. After dissolution of PETg, the nanofillers remained oriented in the thermosetting matrix. The characterization of the obtained nanocomposites has been carried by means of different experimental techniques which provided complementary results.