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Document Type

Open Access Dissertation

Degree Name

Doctor of Philosophy (PhD)

Degree Program

Polymer Science and Engineering

Year Degree Awarded

2017

Month Degree Awarded

September

First Advisor

Ryan C. Hayward

Subject Categories

Polymer Science

Abstract

This thesis broadly aims to design reconfigurable materials through complementary combinations of nanoparticles and polymers. Understanding nanoparticle dispersion pathways and mechanisms is a critical first step in any polymer nanocomposite work as it continues to be a non-trivial subject. To this end, Chapter 2 describes a simple method to control nanoparticle dispersion within polymer melts by photografting random copolymers to selectively reactive nanoparticle ligands. The chapters following focus on harnessing the functionality of well dispersed nanocomposite networks to elicit macro-scale responses. Chapter 3 exploits the unique optical properties of gold nanoparticles in combination with thermally responsive hydrogels and liquid crystalline polymers, along with patterned light to achieve dynamic and reconfigurable buckling of 2D sheets. A considerable amount of work has accumulated dealing with programmed shape transformations of responsive materials, but few have demonstrated reprogrammability and reversibility. As such, engendering the ability to reversibly transform a single material into several 3D shapes adds significant progress to the field. Chapter 4 explores self-sustained oscillatory motion of chemomechanical and thermocapillary systems. Simple machines from the nano- to macro-scale are of great interest, whether it be motivated by biology, environmental clean up, or a new means to perform work. In this light, Section 4.1 describes a new combination of photothermally generated Marangoni flow and curved interfaces that amounts to light-driven sustained oscillations. Finally, Section 4.2 lays the framework for a fundamentally new means to achieve chemomechanical oscillatory motion from a non-oscillatory chemical reaction.

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