Synthesis and Characterization of Novel Phenolic Resin/Siloxane Aerogels via Ambient Pressure Drying

Novel phenolic resin/silicone aerogels (PR-Si) were prepared through a facile sol-gel polymerization and ambient pressure drying process without solvent exchange. Without the addition of an additional catalyst, the hydroxyl condensation reaction between the siloxane oligomer and the phenolic resin resulted in the silicon being incorporated into the PR. The obtained aerogels exhibited high compressive strength (0.84–21.11 MPa) and low thermal conductivities [0.046–0.077 W/(m·K)]. The introduction of a Si–O network structure in the PR effectively improved the mechanical properties and thermal stability of aerogels. It is clear from the TGA plot that the mass loss temperature of the PR-Si aerogel was increased by 73 and 79 °C for the weight loss temperatures of 5 and 10% compared to cured pure PR.