Value‐Added Recycling of Beverage Carton Waste Into Thermoplastic Sandwich Structures With Enhanced Energy Absorption and Damping Properties

ABSTRACT Beverage carton waste, a multi‐layer composite of cardboard, polymer, and aluminum, presents significant recycling challenges for conventional recovery technologies. This work presents a manufacturing process‐oriented method that allows shredded beverage cartons to be incorporated directly into thermoplastic sandwich composite panels without prior separation of the layers. With this approach, value‐added products can be produced while decreasing the need for incineration or landfill disposal. Mechanical tests showed that due to the beverage carton filling, sandwich panels presented improved load‐bearing capacity, energy absorption capacity, and damping. Burning tests showed a reduced burning rate and no dripping compared to pure plastics, which is a favorable safety feature. Innovative and energy‐efficient recycling methods are needed to deal with complex waste that cannot be recycled by standard processes. The proposed method enables scalable production of sandwich composites from post‐consumer waste, for indoor, non‐load‐bearing, or lightly loaded applications.