Functionalizing epoxy-based stereolithography resins using multi-walled carbon nanotubes

The present research explored tailoring the physical properties of stereolithography (SL) epoxy-based resins by dispersing controlled amounts of multi-walled carbon nanotubes (MWCNTs) directly in SL resins prior to layered manufacturing. The effects of dispersed MWCNTs on SL building and mechanical properties of layer manufactured parts were investigated. Mechanical mixing and ultrasonic dispersion provided simple and effective means for dispersing MWCNTs in the SL resin. Each concentration of MWCNTs resulted in a "new" resin requiring modifications to the SL build parameters. Scanning and transmission electron microscopy showed strong affinity between the epoxy resin and the MWCNTs. The dispersion of MWCNTs resulted in improvements in the tensile strength and fracture stress of tensile specimens over the unfilled resin. However, elongation at break was negatively impacted when compared with the unfilled material, and a significantly reduced plastic deformation region was observed in the tensile test results for the nanocomposites.