Novel bio-based nanosheets: Improving the fire safety, electromagnetic shielding and mechanical properties of polylactic acid

In this study, a bio-based additive nanosheet (PP-Fe) with multifunctionality was synthesized using self-assembly technology. The multidisciplinary performance of polylactic acid (PLA) composites with addition of PP-Fe was explored, including fire safety, mechanical properties, ultraviolet resistance (UV), electromagnetic interference (EMI) shielding, and flame retardancy. Good dispersion and interfacial compatibility of PP-Fe give its PLA nanocomposites excellent properties. Loading of 20.0 wt% PP-Fe nanosheets on PLA resulted in significant reductions in the maximum heat release rate (72.7 %), total heat release (41.6 %), and total smoke production (64.7 %). More important, the ultraviolet protection factor (UPF) value for the PLA/20PP-Fe composite was 120 %, which is categorized as excellent UV-shielding. In general, traditional flame retardant approaches significantly reduce mechanical performance. Compared to neat PLA, PLA/20PP-Fe exhibited reinforced mechanical properties. The mechanism of the improved multi-performance of the PLA nanocomposite was also determined.