A5073598692- Supramolecular Self-Assembly in Materials
- Material Dynamics and Properties
- Rheology and Fluid Dynamics Studies
- Chemical Synthesis and Analysis
- Polymer crystallization and properties
- Force Microscopy Techniques and Applications
- Modular Robots and Swarm Intelligence
- Click Chemistry and Applications
- Nanopore and Nanochannel Transport Studies
- Polymer Nanocomposites and Properties
- Hydrogels: synthesis, properties, applications
- Pickering emulsions and particle stabilization
- Electrohydrodynamics and Fluid Dynamics
- Proteins in Food Systems
- Simulation and Modeling Applications
- Nanotechnology research and applications
- Silk-based biomaterials and applications
- Epoxy Resin Curing Processes
- Luminescence and Fluorescent Materials
- Polydiacetylene-based materials and applications
- Block Copolymer Self-Assembly
- Bacteriophages and microbial interactions
- DNA and Biological Computing
- Advanced Materials and Mechanics
- Surfactants and Colloidal Systems
University of Pennsylvania
2018-2025
University of Delaware
2024-2025
California University of Pennsylvania
2019
Philadelphia University
2019
Tianneng Power (China)
2011
Through a combined approach of experiment and simulation, this study quantifies the role entanglements in determining mechanical properties glassy polymer blends. Uniaxial extension experiments on 100-nm films containing bidisperse mixture polystyrene enable quantitative comparison with molecular dynamics (MD) simulations coarse-grained model for glasses, where blends allow us to systematically tune entanglement density both systems. In MD simulations, we demonstrate that not all carry...
Peptide-based materials are diverse candidates for self-assembly into modularly designed and stimuli-responsive nanostructures with precisely tunable compositions. Here, we genetically fused computationally coiled coil-forming peptides to the N- C-termini of compositionally distinct multistimuli-responsive resilin-like polypeptides (RLPs) various lengths. The successful expression these hybrid in bacterial hosts was confirmed through techniques such as gel electrophoresis, mass spectrometry,...
Computationally designed 29-residue peptides yield tetra-α-helical bundles with D2 symmetry. The "bundlemers" can be bifunctionally linked via thiol-maleimide cross-links at their N-termini, yielding supramolecular polymers unusually large, micrometer-scale persistence lengths. To provide a molecularly resolved understanding of these systems, all-atom molecular modeling and simulations bundlemers in explicit solvent are presented. A search over relative orientations the identifies structure,...
The architectural control of the self-assembly a series block polypeptides comprising concatenation an elastin-like peptide and coiled-coil, bundle-forming (ELP-BFPs), has been demonstrated. Assembly of...
Intrinsically disordered proteins (IDPs) yield solutions with tunable phase transition behavior and have been widely applied in designing stimuli-responsive materials. Understanding interactions between amino acid residues of the IDP sequence...
The mechanical properties of glassy polymer thin films change as film thickness decreases below the average molecule size. These changes have been associated with a reduction in interchain entanglements due to confinement and an increase molecular mobility from mobile surface layer. Here, using experiments simulations, we determine how each individually impact failure behavior becomes confined. We utilize custom-built uniaxial tensile tester for ultrathin dark-field optical microscopy...
Coiled-coil 'bundlemer' peptides were selectively modified with allyloxycarbonyl (alloc)-protected lysine, a non-natural amino acid containing an alkene on its side chain. The specific display of this from the coiled-coil surface protein-like specificity enabled residue to be used as covalent linkage for creating peptide networks controllable properties or physical self-assembly bundlemers into unexpected, intricate lattices driven by hydrophobic nature For network formation, both...
Peptides capable of forming homotetrameric coiled-coil bundles are utilized as monomeric building blocks ("bundlemers") to synthesize protein-like hybrid polymers consisting covalently linked microdomains with regularly spaced ethylene glycol repeats via step-growth polymerization employing the highly efficient, bioorthogonal tetrazine (Tz) ligation trans-cyclooctene (TCO). Polymerization Tz and TCO-functionalized peptides in aqueous media under strict stoichiometry at or TCO concentrations...
Although many studies have analyzed the behavior of polymers under 1-D thin film and 2-D cylindrical confinement, knowledge about how confinement geometries with more than one length scale, such as random porous networks, impact is yet to be fully explored. We simulate both entangled unentangled polymer melts confined in a diamond network geometry two characteristic scales, where are likely inhabit multiple interconnected neighboring channels. In all systems chains, radius gyration number...
Dynamics of polymer motion into solvent-filled interstices nanoparticle packings can be controlled by tuning the polymer–nanoparticle interactions, whose effect on rate infiltration is non-monotonic as shown MD simulations.
Computationally designed homotetrameric helical peptide bundles have been functionalized at their N-termini to achieve supramolecular polymers, wherein individual ("bundlemers") are the monomeric units. Adjacent linked via two covalent cross-links. The polymers exhibit a range of conformational properties, including formation rigid-rods with micrometer-scale persistence lengths. Herein, coarse-grained model is used illuminate how molecular features affect rod-like behavior polymers. With...
Surface charge patchiness of different types can influence the solution behaviours colloidal particles and globular proteins. Herein, coiled-coil 'bundlemer' nanoparticles that display only a single type surface (SC) are computationally designed to compare their mixed charge-type (MC) counterparts with both positively negatively charged side chains. Nematic columnar liquid crystal phases discovered in low concentrations SC particles, indicative particle end-to-end stacking into columns...
Although many studies have analyzed the various properties of glassy polymer thin films, failure mode and nonlinear mechanical response only recently received attention. Due to competing effects between reductions in entanglement density increased mobility near free surfaces, it is not clear whether one should anticipate embrittlement or improved ductility. In this study, we constructed films with a bidisperse molecular weight distribution by incorporating short chains as diluents into...
Understanding the structure and dynamics of polymers under confinement has been widespread interest, one class that have received comparatively little attention is ring polymers. The properties non-concatenated can also be important in biological fields because proven to a good model study DNA organization cell nucleus. From our previous study, linear cylindrically confined polymer melt were found segregate from each other as result strong correlation hole effect enhanced by confining...
Block copolymer self-assembly is affected by nanoscale confinement, which has long been known to affect interchain entanglements and dynamics of polymers. While most previous work on confined polymer glasses focused the properties homopolymers, mechanical response glassy block thin films still relatively unexplored. By uniaxially deforming lamellar diblock with different morphologies via molecular dynamic simulations, we demonstrate that toughness fingerprint higher compared homopolymers...