Thermoacoustic Sandwich Panels Produced with Balsawood or Pineapple Fiber as Core and Gmelina arborea Wood as External Veneer

The utilization of composite sandwich panels (CSP) with a core composed of wood or natural fibers presents a sustainable option for building insulation to address climate change. This study aims to produce and assess CSP thermoacoustic insulators by examining their physical, mechanical, acoustic, and thermal characteristics. The panels, with thicknesses of 12 and 19 mm, are constructed using cores of balsawood or pineapple leaves (Ananas comosus) (PALF) variety M2 and melina wood (Gmelina arborea) as veneer. Findings indicate that the density of the panels was from 222 to 266 kg m^–3for CSP-balsawood and from 210 to 303 kg m^–3for CSP-PALF. Regarded water absorption panel values, for CSP-balsawood is between 60 and 69% while for CSP-PALF, it is between 104 and 128%. Swelling values of 0.92–1.53 and 3.4–8.5% are for CSP-balsawood and CSP-PALF, respectively. The CSP-balsawood demonstrated superior modulus of rupture and modulus of elasticity values in static bending in both longitudinal and parallel directions, as well as in compression and tension. Furthermore, with the same core material, the 19 mm CSP exhibited greater density and mechanical properties compared to the 12 mm CSP. Thermal resistance is 0.26 to 0.30 and 0.19 to 0.25 W m^–1K^–1for panels from balsawood and PALF, respectively, with the highest thermal conductivity observed at a 19 mm thickness in both cases. During sound absorption testing, the SAC coefficient was found to be less than 0.33 sound absorption coefficient for different panels, which is characteristic of insulation panels. Results reported that CSP-balsawood is suitable for applications where sound insulation is a priority, whereas those made with PALF are more appropriate when thermal insulation is the primary concern. The fabrication of CSP with natural products enhances energy efficiency, improves spatial conditions, and decreases energy consumption, thereby contributing to climate change mitigation.