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Author ORCID Identifier
https://orcid.org/0000-0003-1628-803X
AccessType
Open Access Dissertation
Document Type
dissertation
Degree Name
Doctor of Philosophy (PhD)
Degree Program
Polymer Science and Engineering
Year Degree Awarded
2074
Month Degree Awarded
February
First Advisor
James J. Watkins
Subject Categories
Nanoscience and Nanotechnology | Polymer and Organic Materials | Semiconductor and Optical Materials | Structural Materials
Abstract
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.
DOI
https://doi.org/10.7275/33232546
Recommended Citation
"HYBRID NANOSTRUCTURED MATERIALS FROM FUNCTIONAL POLYMERS: DESIGN, FABRICATION AND PERFORMANCE" (2023). Doctoral Dissertations. 2773.
https://doi.org/10.7275/33232546
https://scholarworks.umass.edu/dissertations_2/2773
Creative Commons License
This work is licensed under a Creative Commons Attribution 4.0 License.
Included in
Nanoscience and Nanotechnology Commons, Polymer and Organic Materials Commons, Semiconductor and Optical Materials Commons, Structural Materials Commons