Biomassa florestal de madeira: desenvolvimento de revestimentos para bioagregados saturados com PCM visando ao aprimoramento do desempenho físico-mecânico e térmico de matrizes cimentícias

Abstract

Phase Change Materials (PCMs) stand out in civil construction due to their thermal energy storage capacity via latent heat. This study aimed to develop and evaluate wood bioaggregates from the Pinus sp. species saturated with coconut oil, used as PCM, and polymer-mineral coatings for application in cementitious matrices. The methodology consisted of grinding and particle size classification of the wood particles, followed by PCM saturation under vacuum and subsequent encapsulation. Different coating formulations were investigated using epoxy resin, carboxylated styrene-butadiene (XSBR), and cement, mixed with sand, graphite, and copper fillers. The results demonstrated that the epoxy resin and sand coating provided the highest layer thickness at 1412 µm. In contrast, it was evidenced that the combination of graphite and XSBR presented chemical incompatibility, compromising the integrity of the coating, which recorded a mass loss of 3.36%. Regarding the individual thermal evaluation of the particles, the epoxy resin with sand treatment showed a thermal delay of 10.18 minutes during cooling and 9.18 minutes during heating. This technical characterization justified the selection of bioaggregates made of epoxy resin with sand, copper, and graphite for the production of the final cementitious matrices. When evaluating the mechanical performance of the produced specimens, the sand treatment presented a modulus of rupture (MOR) of 5.97 MPa and a modulus of elasticity (MOE) of 370.91 MPa. Finally, the DKK tests confirmed the thermal functionality of the system, where the presence of bioaggregates coated with epoxy resin and sand promoted a thermal delay of approximately 30 minutes during heating and 35 minutes during cooling.