Off-campus UMass Amherst users: To download campus access dissertations, please use the following link to log into our proxy server with your UMass Amherst user name and password.
Non-UMass Amherst users: Please talk to your librarian about requesting this dissertation through interlibrary loan.
Dissertations that have an embargo placed on them will not be available to anyone until the embargo expires.
Author ORCID Identifier
Open Access Dissertation
Doctor of Philosophy (PhD)
Polymer Science and Engineering
Year Degree Awarded
Month Degree Awarded
James J. Watkins
Nanoscience and Nanotechnology | Polymer and Organic Materials | Semiconductor and Optical Materials | Structural Materials
Throughout the past decade, nano-structural composites have paved its way to become the undeniable systems for material scientists to solve the multi-disciplinary challenges. Specifically, the polymer and nanoparticle-based composites have a profound influence in the development of next generation material owing to its lightweight and ease in processability. Furthermore, the synergistic effect of individual components leads to the improved mechanical and optical properties of the formed nanocomposite but fabrication of such materials using scalable approach is still challenging. In this Thesis, we focus on the development of 3D nanomaterials adapting high throughput techniques like soft nanoimprinting lithography (NIL), layer by layer assembly (LBL) and self-assembly of brush block copolymer (BBCP) systems to create flexible opto-electronic devices and high-performance coatings.
High-performance coating built from structural composites is essential in protecting automotive and aircraft parts from particle collisions. Structural nanocomposite coatings with alternating stack of hard and soft domains provides both strength and toughness, but the existing fabrication route is multi-step, and their performance is only examined at low mechanical strains. In Project 1, we utilize the faster self-assembly approach of BBCP with phenolic resin to fabricate highly oriented layered nanocomposite. We delve into studying structure-property relationship at high strain rate using laser induced microparticle projectile impact tests on these nanocomposite coatings. Such fundamental study opens avenues to discover the underlying mechanisms of energy dissipation in well-ordered nanostructures.
Mechano-chromic sensors with narrow spectral response and high sensitivity to strain finds interesting applications in flexible displays and data encryption. Existing strain tunable photonic devices often lose the resolution at larger strains and thus lack color vibrancy. To overcome this, we adopt a novel approach to integrate meta-surface from NIL and photonic crystal from elastomeric materials achieved via LBL in a single device. Project 2 focusses on this integration which allows interference between these two entities and thus offers broad range of color tuning ability with narrow bandwidth in the colorimetric response. Our experimental findings agree well with simulations depicting high feature fidelity of Metasurfaces.
Anti-Reflective coatings (ARCs) are essential in enhancing the performance of optical devices and solar panels. Existing ARCs with low-refractive indices for glass substrates suffers from scattering due to defects and long processing times. In Project 3, we explore fabrication of low-refractive index porous silica from bottle brush templating process and silica precursor with fast heat processing techniques- rapid thermal annealing (RTA). We compare the effect of rapid heating versus conventional heating rates to correlate its influence on structures. In addition to that, low refractive index mesoporous silica thin films have been shown to perform as an effective anti-reflective coating (ARCs). Further, this work also demonstrates the fabrication of 3D porous moth-eye Nano structured films as an ARC with omni-directional and broadband optical performance.
Nuguri, Sravya M., "HYBRID NANOSTRUCTURED MATERIALS FROM FUNCTIONAL POLYMERS: DESIGN, FABRICATION AND PERFORMANCE" (2023). Doctoral Dissertations. 2773.
Creative Commons License
This work is licensed under a Creative Commons Attribution 4.0 License.
Available for download on Thursday, February 01, 2024