Sviluppo di materiale composito Graphene/poliestere dissipativo di cariche elettrostatiche per applicazioni in ambienti corrosivi.

This project has led to the development of a new industrial-aimed thermosetting nanocomposite, capable of electrostatic dissipation while guaranteeing the mechanical properties distinguishing of a glass fiber reinforced composite. The matrix consists in a polyester resin, industrially formulated for glass fiber reinforced composites; commercially available graphene nanoplatelets are being used as the fillers, provided by NanoXplore, Canada; both unreinforced and glass fiber reinforced configurations of the composite has been made. The production process has been chosen accordingly to the scalability need. Filler dispersion has been obtained through high shear mixing and 6 weight concentration were used, namely 0%, 1%, 3%, 5% ,7% and 10%. Samples have been produced by compression molding with previous manual lay-up preparation of the sample; specimens for the tests were cut directly from the plate sample with the help of a table saw and subsequent sandpaper refining. Electrical characterization has identified a percolation threshold in the range 3÷5 wt%, showing an increase in conductivity of over 7 orders of magnitude; cross plane conductivity is as high as 10-4 [S/cm] for the most conductive sample, with in-plane and cross-section conductivities consistently lower by an order of magnitude. The significant increase of permittivity values in the percolated samples suggests a possible suitability for EMI shielding due to absorption mechanism. Tests on mechanical behavior didn't show any clear trend in relation to fillers content, with variations between the samples shown through all the concentration range; overall, the presence of nanofillers don’t seem to significantly affect flexural and strength properties. Finally, the developed nanocomposite met the objective regarding surface and volume conductivity for electrostatic dissipation while maintaining the mechanical properties of the neat reinforced composite.