Abstract

3D printing is the future of manufacturing, limited by material development. Stereolithography is an ideal 3D printing process as it is energy efficient, accurate, fast and capable of forming composite materials. The photocuring of polymers used in this process is integral to society via more applications such as dentistry, coating, and printed circuit boards. However, those photosensitive materials are unstable in daylight during end use limiting their viability for making functional parts in many applications, motivating our work. The ultimate goal is to photocure only with light outside of the solar spectrum on Earth in stereolithography 3D printing, which motivates this work, to produce photostable parts.
While semiconducting nanoparticles have previously been shown to photocure acrylic resins via a free radical mechanism, here we demonstrate, for the first time, that semiconducting nanoparticles are capable of photocuring epoxy cationically. This result is critical because with that achieved, the quantized effect can be used to increase the band gap energy of the nanoparticles to only be sensitive to light outside of the solar spectrum on Earth.
We study both bulk and quantized nanoparticles, propose a reaction mechanism supported by experimental observations, and explore the effects of process variables on the kinetics of the reaction. The intertwining of the engineering of the application, the chemistry of the reactions and the physics of quantum dots makes this thesis a truly rich, interdisciplinary study.