Experimental study on durability and acoustic absorption performance of biomass geopolymer-based insulation materials

The biomass-based insulation materials have been identified as low-embodied energy materials that reduce energy use and CO₂ emissions, particularly in construction. However, as satisfactory insulation material, it must also ensure durability under changing climate conditions. This work investigated the effect of freeze–thaw, wet-dry and cool-heat cycles on the appearance, compressive strength and thermal conductivity of biomass (wheat straw, rice husk and sawdust) geopolymer-based insulation materials. The results showed that, these samples had a good skeleton structure. By contrast, the wheat straw geopolymer-based (WG) samples showed better durability with compressive strength losses of 19.4 %, 1.3 % and 2.6 % in the three modes, respectively. In addition, the WG samples had high sound absorption performance (0.71 at 1028 Hz). This study provides a more systematic analysis of the durability and sound absorption of biomass geopolymer-based insulation materials, which are crucial for their practical application.