Physical Sciences and Mathematics Commons^™

Engineering Multifunctional And Morphologically Diverse Polymer Brush Surfaces, Cassandra M. Reese

Dissertations

The combination of surface-initiated polymerization (SIP) and post-polymerization (PPM) serves as a powerful approach to fabricate complex, multifunctional polymer films, which can be precisely tuned for desired surface engineering applications. Careful manipulation of PPM parameters such as reaction conditions, the tethered brush parameters, and the physical properties of the unbound post-modifier greatly influence the depth of penetration of the post-modifier and the polymer brush compositional heterogeneity. This dissertation focuses on engineering polymer brush surfaces with multifunctional chemistries and tunable morphologies by investigating the PPM parameters that dictate the distribution of post-modifiers on grafted polymer brush surfaces.

The first chapter of …

Design And Synthesis Of Polymer Brush Surfaces With Complex Molecular Architectures And Morphologies, Wei Guo

Dissertations

The combination of surface-initiated polymerization (SIP) and postpolymerization modification (PPM) is a powerful technique for the fabrication of functional soft surfaces. Better understanding the influence of the aforementioned factors on the PPM effectiveness is valuable for fulfilling the potential of the PPM approach for the fabrication of functional soft surfaces. Specifically, by carefully balancing modification reactivity and limitation of mass transport, polymer brush with composition heterogeneity and gradient along the normal direction of the surface otherwise unattainable by methods of direct polymerization can be fabricated via the PPM approach which opens doors to new routes to polymer brush with complex …

Hybrid Inorganic Core- Conjugated Polymer Shell Nanoparticles Prepared By Surface-Initiated Polymerization, Sourav Chatterjee

LSU Doctoral Dissertations

Hybrid core-shell nanoparticles have attracted attention due to their unique characteristics which combine properties of the inorganic core and organic shell in a way that generates new properties which do not exist for the two individual parts. This makes them promising candidates for the design of stimuli-responsive materials, chemo- and biosensors, and various biomedical applications. In this dissertation research, we designed and prepared a series of hybrid environmentally responsive nanoparticles where fluorescent block copolymers, including various combinations of polythiophene (PT), poly(p-phenylene) (PPP), poly(3-hexylthiophene) (P3HT) and polyallene (PA), were grafted on the surface of inorganic nanoparticles using surface-confined Kumada catalyst-transfer polymerization. …

Polymer Surface Engineering Via Thiol-Mediated Reactions, Ryan Matthew Hensarling

Dissertations

Synthesis of polymer brushes to decorate a surface with desired functionality typically involves surface-initiated polymerization (SIP) of functional, but non-reactive monomers. This approach suffers major drawbacks associated with synthesizing sufficiently thick polymer brushes containing surface-attached polymer chains of high molecular weight at high grafting density (i.e. cost, synthetic effort and functional group intolerance during polymerization). The research herein seeks to circumvent these limitations by the decoration of surfaces with polymer chains bearing specific pendent functional groups amenable to post-polymerization modification (PPM). In particular, this dissertation leverages PPM via a specific class of click reactions – thiol-click – that 1) enables …

Surface-Initiated Polymerization As A Novel Strategy Towards Preparation Of Organic Semiconducting Polymer Thin Films, Euiyong Hwang

LSU Doctoral Dissertations

Organic semiconducting polymer thin films are core materials for organic electronics that are conventionally prepared by solution processing techniques. Despite having the advantage of easy and fast thin film manufacturing, solution techniques have intrinsic drawbacks, such as disordered and poor molecular organization in the film (often resulting in poor device performance), as well as insufficient stabilities of the films and resulting devices. To improve this situation, we designed a novel “bottom-up” fabrication of surface-immobilized organic semiconducting thin films through in situ polymerization. This new strategy will allow high degree of control over molecular organization which therefore results in improved free …