This research was motivated by the need to downgauge polypropylene films for high temperature applications to a thickness of 10 to 15 microns. This follows up on recent results from our laboratory --see Ren et al. (2015) pertaining to the use of silane coupling agents in polypropylene-clay nanocomposites. Dry, solvent-free silane treatment was used in the present work to treat organically modified montmorillonite (Nanocor I.44P) for subsequent compounding with a functionalized polymer compatibilizer to prepare masterbatch additives. These additives were let down in a low MFR polypropylene homopolymer in a twin screw extruder. The location of the coupling agent was found to be different here from the case of solvent mediated silane treatment. The resulting compounds with 5 wt% and 8 wt% clay were characterized for morphology (by TEM) and for rheology in dynamic shear and in extensional flow (with an SER fixture mounted on a TA-ARES instrument) and then used to prepare blown films of two different thicknesses. These films were then evaluated for mechanical properties and found to be superior to the neat polymer film. The rheology of the new compounds was modeled in terms of a model with two entanglement networks-- particle attached chains and free chains similar to Sarvestani (2008). W. Ren, A.K. Chaudhary, K. Jayaraman, "Processing Polypropylene Nanocomposites with Silylated Organoclays: Coupling at Edges versus Gallery Faces," Ind. Eng. Chem. Res. doi 10/1021/ie503888t