Synergistic effects of multiwalled carbon nanotubes and core-shell particles on the toughness and physico-mechanical properties of epoxy resin: a systematic study

Abstract

Here, core-shell impact modifier particles (CSIMPs) and multiwalled carbon nanotubes (MWCNs) were used as reinforcing agents for improving toughness and tensile properties of epoxy resin. For this purpose, emulsion polymerization technique was exploited to fabricate poly(butyl acrylate-allyl methacrylate) core- poly(methyl methacrylate-glycidyl methacrylate) shell impact modifier particles with average particle size of 407 nm. It was revealed that using a combination of the prepared CSIMPs and MWCNTs could significantly enhance toughness and tensile properties of epoxy resin. Also, it was observed that the dominant factors in enhancing the fracture toughness of the ternary composites are crack deflection/arresting as well as enlarged plastic deformation around the growing crack tip induced by the combination of rigid and soft particles. The Response Surface Methodology (RSM) with central composite design (CCD) was utilized to study the effects of the amounts of core-shell particles and multiwalled carbon nanotubes on the toughness and tensile properties of epoxy resin. The proposed quadratic models were in accordance with the experimental results with correlation coefficient more than 98%. The optimum condition for maximum toughness, elastic modulus, and tensile strength were 3 % wt. MWCNT and 1.03 % wt. CSIMPs. The sample fabricated in optimal condition indicated toughness, elastic modulus, and tensile strength equal to 2.2 MPa. m1/2, 3014.5 MPa and 40.6 MPa, respectively.