A Bilayer Micro/Nanostructured Water‐Based Paint With Effective Thermal Insulating and Reflective Properties

In this work, the design, optimization and characterization of a new bilayer painting system is reported. The underlying layer is engineered to provide exceptional thermal insulation to the paint through the synergistic effect of hollow perlite microspheres and micrometer-sized cellulose particles incorporated in an acrylic matrix. The external painting layer is a nanocomposite coating composed of an acrylic matrix containing titania nanoparticles, designed to induce the formation of a homogeneous and glossy surface with high reflectance in the Visible (Vis) spectrum as well as in the near-Infrared (NIR) segments NIR-I and NIR-II. Both layers are obtained using an eco-friendly, water-based commercial acrylic matrix. The bilayer painting system is characterized in terms of viscosity of the polyacrylate/fillers mixtures, thermal conductivity, wettability and UV/Vis/NIR reflectance. Moreover, morphological and thermogravimetric analysis are also performed. The obtained results well evidence the effectiveness of the proposed system to develop new thermal paints able to significantly improve the energy efficiency of buildings.