Mechanical properties of epoxy matrix composite reinforced with multi-walled carbon nanotubes

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2019
Yüceer, Kevser.
Improving usage preference of composite material in the aerospace industry brings the requirement of improving mechanical properties of the material. In this thesis, mechanical improvement of epoxy composite materials is analyzed with contribution of functionalized multi-walled CNT with carboxyl group (-COOH) and non-functionalized MWCNT with epoxy for CNT weight fractions of 0.8, 1.0, 1.2, 1.5 and 2.0 wt%. The nanomaterial is dispersed in epoxy resin by calendering mixing method. Functionalization of CNT provides a good wetting of the reinforcement with epoxy matrix due to additional chemical bonding. The fracture toughness is measured using single-edge notch bending tests, flexural strength using three-point bending tests and tensile strength is measured by carrying out tensile tests. In addition, dynamic mechanical analysis is performed to characterize the material. The fracture toughness and storage modulus of reinforced composites are approximately the same with the base material. Fracture toughness is found not to increase for the weight fractions measured. The composites containing 1.5 wt% MWCNT-COOH and 1.2 wt% MWCNT exhibit increases in tensile strength by 20% and flexural strengths by 15%.

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Citation Formats
K. Yüceer, “Mechanical properties of epoxy matrix composite reinforced with multi-walled carbon nanotubes,” Thesis (M.S.) -- Graduate School of Natural and Applied Sciences. Aerospace Engineering., Middle East Technical University, 2019.