Performance of PA6/SEBS-g-MA nanocomposites with carbon nanotubes (MWCNT): Impact of MWCNT content

Abstract

Flexible polymer nanocomposites emerge as promising materials to meet the requirements of strategic sectors such as automotive, packaging, and electronics. In this work, the influence of incorporating multiwalled carbon nanotubes (MWCNTs) at low contents (0.5 and 1 parts per hundred resin, phr) was investigated in a polyamide 6 (PA6)/maleic anhydride-grafted styrene–ethylene–butylene–styrene (SEBS-g-MA) blend. The materials were processed in a twin-screw extruder and molded by injection. The torque reometry properties, impact resistance, tensile strength, X-ray diffraction (XRD), Raman spectroscopy, Fourier-transform infrared spectroscopy (FTIR), differential scanning calorimetry (DSC), and heat deflection temperature (HDT) were evaluated, as well as scanning electron microscopy (SEM). Torque rheometry revealed an increase in torque with the incorporation of SEBS-g-MA into PA6, suggesting enhanced viscosity and compatibility. As a result, tough and flexible nanocomposites were formed at room temperature. FTIR, DSC and XRD analyses indicated the predominance of the α-crystalline phase of PA6 in the nanocomposites, while Raman spectroscopy detected the presence of MWCNTs only at the 1 phr concentration. SEM imaging confirmed increased ductility in the PA6/SEBS-g-MA blend and in the nanocomposites, with good distribution of carbon nanotubes, particularly at 1 phr. Notably, the PA6/SEBS-g-MA/MWCNT (1 phr) nanocomposite exhibited remarkable improvements, 178.9% increase in impact strength, 221.4% increase in elongation at break, while maintaining tensile strength and HDT compared to neat PA6. These findings suggest the potential for producing tailor-made flexible nanocomposites for targeted applications, offering a well-balanced set of properties.