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

## TL;DR

This paper explores the use of natural fiber-based sandwich panels for building insulation, comparing balsawood and pineapple fiber cores with Gmelina arborea veneer.

## Contribution

The study introduces and evaluates thermoacoustic sandwich panels made from balsawood or pineapple fiber cores and Gmelina arborea veneer for sustainable building insulation.

## Key findings

- CSP-balsawood panels showed better mechanical properties and sound insulation compared to CSP-PALF.
- CSP-PALF panels had higher thermal insulation performance but lower mechanical strength.
- Thicker panels (19 mm) exhibited better density and mechanical properties than thinner ones (12 mm).

## Abstract

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–3 for CSP-balsawood and from
210 to 303 kg m–3 for 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–1 K–1 for 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.