Chitosan foam reinforced by SiC whisker for building insulation with high mechanical strength and vapor permeability

Porous foam based on renewable materials has attracted extensive attention in green energy conservation and sustainable development. However, there is still a requisite for biomass-based porous foam that could meet the demand for excellent mechanical and high thermal insulation performances for building insulation. Herein, we demonstrated a facile strategy to prepare a porous foam made from a chitosan matrix reinforced by SiC whisker, which shows good performance in building insulation and mechanical strength. The prepared porous foam has a low density (20.1–54.4 kg m−3) and high porosity (>97.0%). The density of the chitosan-SiC porous foam can be controlled by varying the suspension solid and SiC whisker content in the preparation process. Furthermore, the influences of SiC whisker content on the mechanical properties and thermal conductivity of the porous foams were also investigated. When the content of SiC whisker is 30 wt%, the prepared porous foam has the highest compression modulus of about 89.8 kPa and also low thermal conductivity of 0.0354 W m−1K−1. Moreover, the prepared porous foam shows excellent water vapor permeability with a vapor resistance factor of 2.94, which is beneficial for moisture transfer in buildings. This work provides a facile way to manufacture biomass based porous foam, which is potential for energy saving in buildings.