Electrical and mechanical tuning of 3D printed photopolymer–MWCNT nanocomposites through in situ dispersion

Abstract

An electric field‐assisted in situ dispersion of multiwall carbon nanotubes (MWCNTs) in polymer nanocomposites, fabricated through stereolithography three‐dimensional (3D) printing technique, was demonstrated. The introduction of MWCNTs increased the elasticity modulus of the polymer resin by 77%. Furthermore, the use of an electric field for in situ MWCNT dispersion helped improving the average elongation at break of the samples with MWCNTs by 32%. The electric field also increased the ultimate tensile strength of the MWCNT reinforced nanocomposites by 42%. An increase of over 20% in the ultimate tensile strength of in situ dispersed MWCNT nanocomposites over the pure polymer material was observed. Finally, it was demonstrated that the magnitude and direction of the electrical conductivity of MWCNT nanocomposites can be engineered through the application of in situ electric fields during 3D printing. An increase of 50% in the electrical conductivity was observed when MWCNTs were introduced, while the application of the electric field further improved the electrical conductivity by 26%. The presented results demonstrated the feasibility of tuning both electrical and mechanical properties of MWCNT reinforced polymer nanocomposites using in situ electrical field‐assisted 3D printing. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019, 136, 47600.

3D Printing of Flexible Strain Sensor Array Based on UV‐Curable Multiwalled Carbon Nanotube/Elastomer Composite

“…It is suggested that the increasing elasticity modulus might result from the high stiffness of MWCNTs and the strong interfacial bonding between the MWCNTs and EA. [ 43 ] Additionally, the defects of MWCNT‐based composites increase with the increase in the amount of MWCNTs, leading to a decreased breaking elongation.…”

Nanomaterial Patterning in 3D Printing

“…In addition, Coulombic forces can cause the electrically polarized nanoparticles to migrate toward one another to form a network. However, electrophoresis was not observed in the highlighted works, likely due to the low permeability of the surrounding polymer resin 34,54,331. The result is a highly aligned composite that can be layered to form biomimetic materials.…”

“…Moreover, the magnitude of the electric field, as well as the direction, has a significant effect on the functional properties of the structure. Similar to the method utilized by Yang et al, Chavez et al aligned dispersed MWCNTs by applying an electric field during SLA printing to fabricate MWCNT‐photopolymer nanocomposites 331. Samples with MWCNTs aligned parallel as well as perpendicular to the test direction improved mechanical and electrical properties with respect to samples with randomly aligned MWCNTs.…”

“…In summary, electrical patterning leverages electric fields to program the morphology of extruded ink and pattern nanomaterials reinforcement. Electrical patterning is used to directly produce patterned nanomaterials, including nanoscale fibers32,100 and droplets314 or to program the alignment of nanomaterial reinforcement 33,34,54,331. Electrical patterning is used to produce functional structures with anisotropic electrical, optical, and mechanical properties due to tailored anisotropy, as well as fine microstructures of highly aligned nanofiber grids.…”

Multi-scale Characterization and Visualization of Metallic Structures to Improve Solid Mechanics Education

“…Our goal is to design and experiment with new approaches to help students understand the relationship between material structure, processing, and properties. In contrast to conventional and subtractive manufacturing methods, additive manufacturing (AM) uses layer-bylayer build-up of parts, and has become popular for fast prototyping and final production [4][5][6][7][8][9][10]. Several metallic materials, including structural steel, aluminum, titanium, and copper, can be processed by AM with outstanding properties.…”