With a carbon neutrality horizon in 2050 as target for the industry, the use of growing quantities of recycled and recyclable materials is key. “Greenflocks” chips urethane based poroelastic material coming from recycled PU mattresses, that are decontaminated, shredded, mixed with thermoplastic bi-component PET fibers as well as thermofixed with hot air ovens resulting in low Volatile Organic Component (VOC) and odors, seems to be a good candidate. Indeed, one gets a 80 % recycled poroelastic material, 100% recyclable, with mechanical and acoustical properties allowing between 10 % and 20 % weight reduction compared to shoddy cotton felt typically depending on the density. Indeed, this “Greenflocks” material presents excellent mechanical decoupling properties even at high densities for the low thickness areas above 150 kg/m3 and up to 300 kg/m3 typically with a Young’s modulus kept below 150 kPa.
For Hybrid stiff Greenflocks dash insulator applications, where two chips urethane blanks, one hard and one soft, are superposed separated by a glued film, going up to a 2000 g/m2 equivalent barrier is usually the upper mass per unit area limit keeping reasonable airflow resistances. Knowing that heavy layer barriers below 1800 g/m2 down to 600 g/m2 are complicated to source, expensive as well as too soft to be easily manipulated, the use of powdered heavy carpet scraps below the “Greenflocks” hard layer backed by a film proved to be working as well as if it were directly backfoamed. By the way, the recycled content of these heavier hybrid stiff insulators is therefore increasing also… A Life Cycle Assessment of the “Greenflocks” chips urethane based poroelastic material will be shown in this paper as well as acoustic validations on vehicle for various NVH performance targets and applications like dash insulators, carpet insulators etc...