The melt blending method was applied to prepare ternary composites of polypropylene (PP)/organic-rectorite (OREC)/polyethylene-octene elastomer (POE) at constant content of 2 phr (parts per hundred PP) of OREC and 5, 10, 15 phr of POE (named PRE25, PRE210, and PRE215, separately) via twin-screw extruder. At the same time the binary composites of OREC/PP at 2 phr loading of OREC, named PR2 were prepared in order to investigate effects of OREC and POE on rheology and crystallization properties of composites. The rheology was characterized on capillary rheometer, nonisothermal crystallization kinetics on differential scanning calorimetry (DSC), and thermal stability properties on thermogravimetric analysis (TG). It is found that melting PR2 and PRE systems conform to the law of Non-Newton and shear-thinning behavior is observed for both systems. The apparent viscosity of the melt decreases with the increase of POE loadings. The crystallization half-time (t(1/2)) of PRE is shorter, the rate constant Zc larger, which indicates OREC and POE has the heterogeneous nucleation effect and the crystallization rate of PP was increased. The enthalpy of PRE is lower than that of PR2 and pure PP at the same conditions, which shows that the relative crystallinity of PRE composites are reduced. TG curves show that the ternary systems have higher thermal stability in contrast with pure PP. (C) 2005 Wiley Periodicals, Inc.