Mechanical properties of carbon monoxide reduced graphene-polyamide-6 nanocomposites prepared by melt-mixing

Carbon monoxide reduced graphene (CO-rG) was compounded with polyamide-6 (PA6) by melt-mixing to investigate the suitability of CO-rG as novel filler for enhanced mechanical properties in PA6-based composites. CO-rG was first exfoliated via probe ultrasonication in p-xylene prior to melt-mixing. Nanocomposites of differing compositions were then prepared and characterised for their elastic modulus (E), tensile yield strength (σyield), and strain at break (εb). Interactions between CO-rG and PA6 were characterised via Fourier-transform infrared (FTIR) spectroscopy and observed via scanning electron microscopy (SEM). Significantly enhanced mechanical properties were achieved even at low CO-rG content, with mechanical percolation observed at 1.0 %·w/w CO-rG. Beyond the mechanical percolation concentration, the addition of 6.0 %·w/w CO-rG resulted in overall enhancement in bulk composite properties with a measured E and σyield of 4107±225 MPa and 62±1 MPa, respectively. FTIR spectroscopy confirmed the existence of hydrogen bonding between CO-rG and PA6. SEM imaging indicated uniform dispersion of CO-rG in PA6.