Polymerized high internal phase emulsion of poly(divinylbenzene), poly(DVB)polyHIPE filled with porous clay has been successfully prepared. The hybrid organic-inorganic porous clay heterostructures (HPCH) were obtained from a reaction of organo-modified bentonite, surfactant, and tetraethoxysilane (TEOS)/methyltetraethoxysilane (MTS) occurring in the galleries of the clay mineral. HPCH loadings of 1, 3, 5, and 10 wt % were added to the highly porous material, formed by the high internal phase emulsion technique (HIPE). The effects of the inorganic filler on surface area, morphology, thermal, and mechanical properties were studied by N-2 adsorption-desorption (Autosorb I), scanning electron microscopy (SEM), thermogravimetric analysis (TGA), and a Lloyd universal testing machine, respectively. Results showed that the presence of layered silicate in the polymer matrix resulted in the enhancement of physical properties of the foams filled with hybrid organic-inorganic porous clay heterostructures (HPCH). Mechanical properties, including compressive stress and Young's modulus, were found to be improved by up to 84% and 137%, respectively, when compared with neat poly(DVB)polyHIPE foams. The best mechanical properties of the obtained material were achieved at 5 wt % loading of HPCH. The use of HPCH as the reinforcing agent of poly(DVB)polyHIPE was also capable of improving the surface area of the obtained materials by 35-97%. It was clearly demonstrated in this study that the suitable content of HPCH, i.e., 5 wt %, has an effect on improving the mechanical properties and surface area of the poly(DVB)polyHIPE foams. (C) 2009 Wiley Periodicals, Inc. J Appl Polym Sci 114: 3041-3048, 2009