Polyethylene/poly(3-hydroxybutyrate-co-3-hydroxyvalerate/carbon nanotube composites for eco-friendly electronic applications

The development of new conducting composites, for electric and electronic applications, with lower environmental impact is a relevant issue. Blending poly (3-hydroxybutyrate-co-3-hydroxyvalerate (PHBV) with high-density polyethylene (HDPE), 50/50 HDPE/PHBV, and multiwalled carbon nanotubes (MWCNTs) (3.5 and 7.5%), represents a suitable strategy for improving sustainability of conducting polymers while maintaining procesability and functional performance. The study focuses on thermal, mechanical, morphological, rheological, electrical properties and EMI shielding effectiveness. Composites show a morphology in which MWCNTs remains in HDPE phase. Without compatibilizer, only the composite with 7.5% of MWCNTs achieves a conductivity value suitable for reaching 20 dB of electromagnetic shielding. In composites with PE grafted with maleic anhydride (0.5%) the electrical conductivity substantially increased, achieving a suitable EMI shielding level with lower proportion of nanotubes (5 wt%). Summarizing, composites with reduced environmental impact, suitable for EMI shielding applications, have been obtained optimizing the MWCNTs amount and their dispersion.