(565a) 3D Printed Polymer/Nanoparticle Layered Structures

3D printing has been applied in automobile, aerospace, biomedical, pharmaceutical, and plastics recycling field. 3D printing has an advantage over traditional manufacturing in processing composite materials because of their capability in managing multi-materials at multi-scales. More importantly, 3D printing can process solids (e.g., filaments and powders), liquids (e.g., inks and solutions), and gels (e.g., polymer or blend networks). One challenge in additive manufacturing that remains to be solved so far is the printing resolution at nanoscale. Our research is seeking innovation to add one layer of nanoparticles on polymer surfaces for layered structures with unique properties. In this project, the layer-by-layer assembly was merged on the 3D printing platform. The first layer of polymers was controlled with precise dimensions and morphologies, depending on which the nanoparticles were organized with long-range orders and controlled orientations. Simple materials of UV-light-sensitive monomers and carbon nanofibers (CNFs) were used for demonstrating the feasibility of composite processing. The CNFs were found to anchor on specific surface features (i.e., rough surface with comparable nanoparticle sizes). The prepared polymer/nanoparticle composites were used as environmental and health-monitoring sensors for liquid and gas chemicals. It was found that the prepared nanocomposites can serve as chemiresistors that function precisely as responses to chemical solvents, volatile organic compounds, and mechanical strains. The high sensitivity and selectivity of these sensors from our 3D printing shed light on rapid prototyping of electrical, mechanical, and other devices with complex structures.