A5036623197- Rheology and Fluid Dynamics Studies
- Polymer crystallization and properties
- Material Dynamics and Properties
- Advanced biosensing and bioanalysis techniques
- Gold and Silver Nanoparticles Synthesis and Applications
- Surface Modification and Superhydrophobicity
- Micro and Nano Robotics
- Spectroscopy and Quantum Chemical Studies
- Parallel Computing and Optimization Techniques
- Advanced Theoretical and Applied Studies in Material Sciences and Geometry
- Polymer Nanocomposites and Properties
- Theoretical and Computational Physics
- Supramolecular Self-Assembly in Materials
- Cloud Computing and Resource Management
- Advanced Materials and Mechanics
- Modular Robots and Swarm Intelligence
- Distributed and Parallel Computing Systems
- Advanced Polymer Synthesis and Characterization
- Biosensors and Analytical Detection
- Polymer Surface Interaction Studies
- Adsorption, diffusion, and thermodynamic properties of materials
- Microplastics and Plastic Pollution
- DNA and Nucleic Acid Chemistry
- Composite Material Mechanics
- nanoparticles nucleation surface interactions
Princeton University
2021-2024
Max Planck Institute for Polymer Research
2010-2017
Brookhaven National Laboratory
2013-2017
Center for Functional Nanomaterials
2013-2016
Brookhaven College
2013
Max Planck Society
2012
City College of New York
2008-2010
Molecular dynamics simulations were conducted to investigate the structural properties of melts nonconcatenated ring polymers and compared linear polymers. The longest rings composed N=1600 monomers per chain which corresponds roughly 57 entanglement lengths for comparable For rings, radius gyration squared was found scale as N 4/5 power an intermediate regime 2/3 larger indicating overall conformation a crumpled globule. However, almost all beads are "surface beads" interacting with other...
Molecular dynamics simulations were conducted to investigate the dynamic properties of melts nonconcatenated ring polymers and compared linear polymers. The longest rings composed N = 1600 monomers per chain which corresponds roughly 57 entanglement lengths for comparable found diffuse faster than their counterparts, with both architectures approximately obeying a D ∼ N(-2.4) scaling law large N. mean-square displacement center-of-mass follows sub-diffusive behavior times distances beyond...
Ring polymers remain a challenge to our understanding of polymer dynamics. Experiments are difficult interpret because the uncertainty in purity and dispersity sample. Using both equilibrium nonequilibrium molecular dynamics simulations we have investigated structure, dynamics, rheology perfectly controlled ring-linear blends chains up about 14 entanglements per chain, comparable experimental systems. Linear contaminants increase zero-shear viscosity ring melt by 10% around one-fifth their...
Steady-state shear viscosity η(γ̇) of unconcatenated ring polymer melts as a function the rate γ̇ is studied by combination experiments, simulations, and theory. Experiments using polystyrenes with Z ≈ 5 11 entanglements indicate weaker thinning for rings compared to linear polymers exhibiting power law scaling η ∼ γ̇–0.56 ± 0.02, independent chain length, Weissenberg numbers up about 102. Nonequilibrium molecular dynamics simulations bead-spring model reveal similar behavior γ̇–0.57 0.08 4...
We study the problem of self-assembly nanoparticles (NPs) into finite mesoscopic structures with a programmed local morphology and complex overall shape. Our proposed building blocks are NPs that directionally functionalized DNA. The combination directionality selectivity interactions allows one to avoid unwanted metastable configurations, which have been shown lead slow kinetics even in much simpler systems. With numerical simulations, we show variety target objects can be designed...
DNA-driven assembly of nanoscale objects has emerged as a powerful platform for the creation materials by design via self-assembly. Recent years have seen much progress in experimental realization this approach three-dimensional systems. In contrast, two-dimensional (2D) programmable nanoparticle (NP) systems are not well explored, part due to difficulties creating such Here we demonstrate use charged liquid interfaces and reorganization 2D DNA-coated NPs. The absorption NPs surface is...
The motion of nanoparticles (NPs) in entangled melts linear polymers and nonconcatenated ring are compared by large-scale molecular dynamics simulations. comparison provides a paradigm for the effects polymer architecture on dynamical coupling between NPs nanocomposites. Strongly suppressed with diameter d larger than entanglement spacing is observed melt before onset Fickian NP diffusion. This strong suppression occurs progressively as exceeds related to hopping diffusion network. In...
The dynamic behavior of a nanodroplet pure liquid on wetting gradient was studied using molecular dynamics simulation. spontaneous motion the droplet is induced by force imbalance at contact line. We considered Lennard–Jones system as well water self-assembled monolayer (SAM). for case found to be steady with simple power law describing its center-of-mass position time. depend uniformity gradient, which composed methyl- and hydroxyl-terminated alkanethiol chains Au(111). When nonuniform...
To study the conformational properties of unknotted and nonconcatenated ring polymers in melt, we present a detailed qualitative quantitative comparison simulation data obtained by molecular dynamics using an off-lattice bead-spring model Monte Carlo lattice model. We observe excellent, sometimes even unexpectedly good, agreement between results for many quantities measured including gyration radii polymers, their subchains, contact probabilities, surface characteristics, number contacts...
The wetting behavior of water nanodroplets on homogeneous and phase separated self-assembled monolayers (SAMs) composed CH3(CH2)10SH HOCH2(CH2)10SH Au(111) was studied using molecular dynamics simulation. A simple model is introduced for the SAM where only top eight or ten atomic layers are considered. For CH3– HOCH2–terminated chains uniformly mixed. With χp denoting mole fraction HOCH2-terminated chains, we report equilibrium contact angles droplets 4000 molecules = 0, 0.25, 0.5, 0.75, 1....
We propose a general strategy of “sequential programmable self-assembly” that enables bottom-up design arbitrary multi-particle architectures on nano- and microscales. show naive realization this scheme, based the pairwise additive interactions between particles, has fundamental limitations lead to relatively high error rate. This can be overcome by using cooperative interparticle binding. The cooperativity is well known feature many biochemical processes, responsible, e.g., for signaling...
We study numerically the possibility of programmable self-assembly various thin-shell architectures. They include clusters isomorphic to fullerenes C20 and C60, finite infinite sheets, tube-shaped toroidal mesostructures. Our approach is based on recently introduced directionally functionalized nanoparticle platform, for which we employ a hybrid technique Brownian dynamics with stochastic bond formation. By combining number strategies, were able achieve near-perfect yield desired structures...
ADVERTISEMENT RETURN TO ISSUEPREVNoteNEXTReply to Comment on "Entangled Polymer Melts: Relation between Plateau Modulus and Stress Autocorrelation Function"Won Bo Lee†‡, Jonathan Halverson†, Kurt Kremer*†View Author Information† Max Planck Institute for Research, Ackermannweg 10, 55128 Mainz, Germany‡ Department of Chemical Biomolecular Engineering, Sogang University, 1 Sinsu-dong, Mapo-gu, Seoul 121-742, South Korea*Corresponding author. E-mail: [email protected]Cite this: Macromolecules...