Some Studies on the Mechanical Properties of Rubber Toughened Epoxy/CTBN Matrix in the Presence of Clay and Carbon Nanotubes (CNT) as Nanofillers Bhagwan F. Jogia*, Madan Kulkarnib, P.K. Brahmankara and D. Ratnab aDepartment of Mechanical Engineering, Dr. Babasaheb Ambedkar Technological University, Lonere, Raigad 402103, Maharashtra State, India. bfjogi@dbatu.ac.in bNaval Materials Research Laboratory (DRDO), Ambernath, Mumbai, Maharashtra State, India Rubber toughened blends of epoxy and carboxyl group terminated butadiene nitrile (CTBN) was selected as a system for this study. CTBN was used as toughening agent with different concentrations of CTBN with epoxy. 0, 5, 10, 15 and 20 parts per hundred parts resins (phr) are the combinations were prepared by varying CTBN content in epoxy. Some testing and analysis is carried out initially for the optimization. It is observed that 15 phr epoxy/CTBN depicts improvement in the mechanical properties; such as tensile properties and dynamic mechanical thermal analysis (DMTA). Furthermore, clay and carbon nanotubes (CNT) as nanofillers were filled in the rubber toughened epoxy/CTBN polymer matrix to prepare polymer nanocomposites. The system is optimized and found that 3 wt % of clay with 15 phr epoxy/CTBN blends shows improvement in the mechanical properties. However, 0.5 wt% of modified CNT depicts improvement in the properties. It may be due to highly exfoliation of clay and good dispersion of the CNT in the rubber toughened epoxy/CTBN polymer nanocomposites (PNC). Scanning electron microscopy (SEM), Differential scanning calorimetric (DSC) analysis and Thermogravimetric analysis (TGA) were carried out on the few selective samples for further study and analysis. Keywords: Epoxy, Mechanical properties, Polymer nanocomposites (PNC), Nanofillers, Clay, Carbon nanotubes (CNT). Corresponding and presenting author: Dr. Bhagwan F. Jogia* Email ID: bfjogi@dbatu.ac.in, bfjogi@gmail.com