This invention provides composite materials that combine the material properties of hydrophobic polymers with internal structure and order provided by polymerization of lyotropic liquid crystals (LLCs). Composites, particularly nanocomposites, are made by forming a LLC assembly that has hydrophobic regions and hydrophilic regions, combining hydrophobic polymer in the assembly and polymerizing the polymerizable LLC monomers in the assembly. The hydrophobic polymer, polymerized LLC assembly or both can be crosslinked in the composite. Nanoporous composites, particularly those with uniform-sized pores and/or with uniform pores distribution can be prepared in this way. In addition, complex polymers in which a second polymeric material, which may be organic or inorganic, can be introduced into the pores or other structural features of the composite can be prepared. Adding flexible hydrophobic polymers to the LLC assembly increases the flexibility and toughness of the resultant polymerized composite material to provide improved composite materials for use as membranes and in other applications. Hydrophobic polymer addition can also increase the diffusion resistance in the organic phase of the composite. Of particular interest are composites in which the hydrophobic polymer is butyl rubber or related synthetic rubber.