Development of Hemp/PLA based sustainable headliner for automotive interiors

Abstract

This study developed a sustainable automotive headliner using a hemp/PLA composite as the headliner board and an r-PET (recycled polyester) fibrous nonwoven mat as a foam replacement. The layers were joined with specialized headliner adhesives and evaluated for thermal and sound insulation properties. Hemp fibers were cut to 50 mm lengths to form a fiber mat. The composite was fabricated by stacking PLA films and hemp fiber web, then consolidating to 4 mm thickness via compression molding at elevated temperature. Composites with hemp fiber weight fractions of 40%, 50%, and 60% were prepared and tested for mechanical properties. Thermal bonded r-PET/low-melt polyester nonwoven fabrics with three areal densities were produced from blended webs. The complete headliner, assembled by laminating the hemp/PLA composite, nonwoven fabric, and knitted inner layer using adhesives, exhibited promising thermal and sound insulation. It offers potential as a foam-free alternative for automotive headliners.