Thermal, Acoustic, and Hygrothermal Properties of Recycled Bovine Leather Cutting Waste-Based Panels with Different Compositions

This study aims to investigate the thermo-acoustic and hygrothermal properties of innovative panels made of leather waste produced by a bag factory from a circular economy perspective. Their performance was compared with other residual-based insulation panels. The leather scraps were chipped and three boards were fabricated by means of a mold with different compositions, adding adhesive glue. In order to improve the sustainability aspects, a sample was assembled by using a water-based polyurethane glue, in addition to the two panels with vinyl glue. Panels were tested for thermal, acoustic, and hygrothermal performance. Thermal conductivity values in the range of 0.064-0.078 W/mK at 10 degrees C were measured depending on the composition and the adhesive. A slight thermal performance deterioration occurs when using the natural water-based glue. The samples were characterized by good performance both in terms of sound absorption coefficient (Noise Reduction Coefficient NRC = 0.21-0.28) and Transmission Loss, up to 59 dB values. Water vapor resistance factor values in the 35-48 range were obtained, close to the values of standard materials, such as expanded polystyrene and polyurethane.