Advances in polymer aerogels

Aerogels are the nanoporous materials consisting of hierarchical 3D assemblies of nanoparticles, which are derived from sol-gel process combined with drying methods. Recently, polymer aerogels have been considered as a candidate material in various fields such as thermal insulation, adsorption, energy storage due to the unique characteristics, including ultra-low thermal conductivity, ultralight density, high porosity, low dielectric constant, excellent mechanical behavior and flexible molecular designing. This paper gives a comprehensive review about the recent progresses in preparation, structures, properties and applications of some common varieties of polymer aerogels, including polyurethane (PU), polyurea (PUA), polyimide (PI), polybenzoxazine (PBZ) and syndiotactic polystyrene (sPS) aerogels, as well as a brief prospect over the future research directions of this field.