1. Studying the Effects of Functionalized Multi-walled Carbon Nanotubes on Mechanical and Thermal Properties of Epoxy Composites Nasim Hadiashar 1, Prashanth Asuri 1, Navid Babhadiashar 2 1 Department of Bioengineering, Santa Clara University, Santa Clara, CA 2 Thermo Fisher Scientific, Santa Clara, CA

2. Outline  Introduction  Purpose of the study  Advantages of using Epoxy composite  Functionalization of Multi-walled Carbon Nanotubes (MWCNTs)  Experimental Results and Conclusions

3. Advantages of using Epoxy composites – High strength – High stiffness – Low weight – Corrosion resistance Elements of the Epoxy Resin 1.40% High viscosity Epon 828 2.60% Low viscosity Epon 1001F 3.10% Curing agent Dyhard D50EP 4.2% Hardener Dicy UR-500 Epoxy composites

4. Advantages of using MWCNTs – Known to improve mechanical properties of a variety of materials (e.g. polymers, elastomers, etc.) – Fabricating lighter composites Disdvantages of using MWCNTs – High cost – Poor dispersion and interfacial bonding with the bulk materials – Agglomeration at higher concentrations Multi-walled Carbon Nanotubes (MWCNTs)

5. Functionalization of MWCNTs Advantages: improves compatibility between bulk matrix and MWCNTs Method a.Acid treatment b.Covalent functionalization with amine or carboxyl groups

6. Experimental Results Thermogravimetric analysis

7. Experimental Results Onset decomposition temperature

8. Sample 5 °C/min10 °C/min20 °C/min T o (°C)T p (°C)ΔΗ (J/g)T o (°C)T p (°C)ΔΗ (J/g)T o (°C)T p (°C)ΔΗ (J/g) Neat119132336131144326143158301 1 wt% Amine- MWCNTs 120133316132144.5327144157308 1 wt% Carboxyl- MWCNTs 123134321133145.5330146159.5326 1 wt% Raw MWCNTs 119.5132293.6130142.5314.2141154286 Experimental Results Differential scanning calorimetry (DSC) Experiments for Neat, 1 wt% Amine-MWCNTs, 1 wt% Carboxyl-MWCNTs, and 1 wt% Raw MWCNTs samples carried out at different heating rates of 5, 10, and 20 °C/min.

9. Experimental Results Tensile testing

10. Experimental Results Young’s Modulus testing

11. Conclusions  Amine/carboxyl-functionalized MWCNTs lead to better improvements in relative to raw MWCNTs  Raw MWCNT samples showed a marked decrease in epoxy mechanical properties  Optimum loading of functionalized MWCNTs is less than 0.5 wt%