Optimizing thermal insulation of waterborne acrylic coatings through controlled integration of hydrophobic silica aerogel: Experimental insights and advanced modeling

This research introduces a thermal insulation coating composed of hydrophobic silica aerogel dispersed in waterborne acrylic resin. To preserve aerogel's insulating efficiency, a waterborne resin was employed to limit resin intrusion into aerogel pores. Experimental evaluation of thermal conductivity using thermal resistance superposition demonstrated a significant decrease in thermal conductivity, achieving up to 46 % reduction at 50 vol% aerogel loading. Analytical modeling using Maxwell and Bruggeman models, alongside finite element simulations, revealed that the observed experimental performance was impaired by partial resin intrusion into aerogel pores, confirmed through thermogravimetric analysis (TGA). The intrusion depth and its impact on insulation efficiency were quantitatively modeled using a core-shell approach, providing a foundation for future optimization strategies.