Upcycling automotive recyclate and miscanthus derived-biocarbon for sustainable composite in automotive applications

We develop impact-toughened sustainable composites from recycled polypropylene (r-PP) obtained from waste automotive parts, pyrolyzed miscanthus biomass (biocarbon) as a filler, and maleic anhydride-grafted polypropylene (MAPP) as a compatibilizer. rPP was blended with an ethylene-octene copolymer (EOC) to improve impact resistance. Biocarbon and MAPP were added to recover stiffness and enhance thermal/dimensional stability.

The addition of EOC to the biocarbon-filled composite improved notched Izod impact strength by 21%. Adding 20 wt% biocarbon increased the tensile and flexural moduli by 17% and 10%, respectively, lowered the coefficient of linear thermal expansion (CLTE) by ~11% in the flow direction and ~17% in the normal direction, and increased the heat deflection temperature by 18%. Density remains ≤ 1 g cm⁻³ with a total sustainable content of 75 %.