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Dynamics In Polymer Nanocomposites Containing Fixed And Mobile Nanoparticles, Chia-Chun Lin Jan 2015

Dynamics In Polymer Nanocomposites Containing Fixed And Mobile Nanoparticles, Chia-Chun Lin

Publicly Accessible Penn Dissertations

This dissertation describes experimental studies on the dynamics of polymer nanocomposites (PNC), namely, center-of-mass (COM) polymer diffusion in PNCs, and COM nanoparticle (NP) diffusion in polymer melts. Elastic recoil detection (ERD) is used for polymer diffusion studies and Rutherford backscattering (RBS) is used for NP diffusion studies. Diffusion of the tracer polymer, deuterated poly(methyl methacrylate) (dPMMA) is slowed down in a PMMA matrix filled with hydroxyl-capped spherical silica nanoparticles. A confinement parameter, ID/2Rg, where ID is interparticle distance and 2Rg is probe size is defined to account for the NP crowding effect. For highly crowded region where ID ...


Non-Specific Interactions Between Cationic Nanoparticle-Polymer Composites And Biomolecules, Matthew Alexander Caporizzo Jan 2014

Non-Specific Interactions Between Cationic Nanoparticle-Polymer Composites And Biomolecules, Matthew Alexander Caporizzo

Publicly Accessible Penn Dissertations

This dissertation describes the consequences of non-specific binding between cationic nanoparticles (NPs) and biological materials ranging from persistence length reduction of single actin filaments, to modified kinetics of myosin V motility, and culminating with correlating THP-1 cell metabolic stress to viscoelastic changes. The bulk of the thesis (chapters 3-5), utilizes optically transparent polymer-NP composites with controllable hierarchical roughness to tune the interaction strength between actin filaments and the surface and impact myosin V kinetics. To generate hierarchical roughness, precise control over the thermodynamics and dynamics of NH2-functionalized NPs in polystyrene-ran-acrylic acid (SAA) is demonstrated in chapter 3. In ...