Multi material, fibers, particles, micro scale, nano scale, functional
Spherical micro- and nano-particles have found widespread use in many various applications from paint to cosmetics to medicine. Due to the multiplicity of desired particle material(s), structure, size range, and functionality, many approaches exist for generating such particles. Bottom-up methods such as chemical synthesis have a high yield and work with a wide range of materials; however, these processes typically lead to large polydispersity and cannot produce structured particles. Top-down approaches such as microfluidics overcome the polydispersity issue and may produce a few different structures in particles, but at lower rates and only at the micro-scale. A method that can efficiently produce uniformly-sized, structured particles out of a variety of materials and at both the micro- and nano-scales does not yet exist. Over the past few years, I have developed an in-fiber particle fabrication method that relies on a surface tension-driven fluid instability, the Plateau-Rayleigh capillary instability (PRI). Thermal treatment of a multimaterial core/cladding fiber induces the PRI, causing the initially intact core to break up into a periodic array of uniformly-sized spherical particles. During this time, I have demonstrated that this method can produce particles from both polymers and glasses, in a multiplicity of structures, and from diameters of over 1 mm down to 20 nm. Furthermore, by using a stack-and-draw method, a high density of cores may be incorporated into a single fiber, making the in-fiber PRI approach a highly scalable process. Finally, I have shown that it is possible to add dopants to the particles to give them functionality. By structuring the particles, it is thus possible to fabricate multi-functional particles whose functionalities may be allocated arbitrarily throughout the volume of the particles.
Doctor of Philosophy (Ph.D.)
College of Optics and Photonics
Optics and Photonics
Optics and Photonics
Length of Campus-only Access
Doctoral Dissertation (Open Access)
Dissertations, Academic -- Optics and Photonics; Optics and Photonics -- Dissertations, Academic
Kaufman, Joshua, "Multifunctional, Multimaterial Particle Fabrication Via an In-Fiber Fluid Instability" (2014). Electronic Theses and Dissertations. 4803.