Silica-based organogels, including aerogels, incorporating hexahydrotriazine and/or hemiaminal species are described. These organo-silica gel materials can have applications as insulating materials. In a particular example, an aerogel includes silica groups and a hexahydrotriazine moiety with at least one nitrogen atom that is covalently linked to a silica group. Methods of making such silica-based organogels are also described.