Disclosed are porous, low density nanoclay composites that exhibit highly homogeneous microcellular morphology and methods for forming the nanocomposites. The nanocomposites include a three-dimensional matrix having a non-lamellar, generally isotropic cellular structure with little or no macroscopic pores. The nanocomposites also include a gel that may be a noncovalently cross-linked, thermoreversible gel. The nanocomposites may include a binder and/or fibrous reinforcement materials. The nanocomposites may be formed according to a freeze-drying process in which ice crystal growth is controlled to prevent formation of macroscopic pores in the composite materials.