25 research outputs found
Molecular simulation of surface-modified polymer vesicle designed for gene and drug delivery
āđāļāļĢāļāļāļēāļĢāļŦāļāļķāđāļāļāļēāļāļēāļĢāļĒāđāļŦāļāļķāđāļāļāļĨāļāļēāļ āļāļĢāļ°āļāļģāļāļĩ 254
Mechanical Properties of Glassy Polyethylene Nanofibers via Molecular Dynamics Simulations
The extent to which the intrinsic mechanical properties of polymer fibers depend on physical size has been a matter of dispute that is relevant to most nanofiber applications. Here, we report the elastic and plastic properties determined from molecular dynamics simulations of amorphous, glassy polymer nanofibers with diameter ranging from 3.7 to 17.7 nm. We find that, for a given temperature, the Youngâs elastic modulus E decreases with fiber radius and can be as much as 52% lower than that of the corresponding bulk material. Poissonâs ratio Î― of the polymer comprising these nanofibers was found to decrease from a value of 0.3 to 0.1 with decreasing fiber radius. Our findings also indicate that a small but finite stress exists on the simulated nanofibers prior to elongation, attributable to surface tension. When strained uniaxially up to a tensile strain of Îĩ = 0.2 over the range of strain rates and temperatures considered, the nanofibers exhibit a yield stress Ïy between 40 and 72 MPa, which is not strongly dependent on fiber radius; this yield stress is approximately half that of the same polyethylene simulated in the amorphous bulk.DuPont MIT AllianceDuPont (Firm) (Young Professor Award
Molecular simulation of surface-modified polymer vesicle designed for gene and drug delivery: monte carlo simulations of grafted polymers between two walls
āđāļāļĢāļāļāļēāļĢāļŦāļāļķāđāļāļāļēāļāļēāļĢāļĒāđāļŦāļāļķāđāļāļāļĨāļāļēāļ āļāļĢāļ°āļāļģāļāļĩ 254
Monte carlo simulation of bidisperse melt polymer brushes
āđāļāļĢāļāļāļēāļĢāļŦāļāļķāđāļāļāļēāļāļēāļĢāļĒāđāļŦāļāļķāđāļāļāļĨāļāļēāļ āļāļĢāļ°āļāļģāļāļĩ 254
Computational molecular modeling of polymer solid electrolytes II: multiscale molecular modeling of amorphous polyethylene oxide
āđāļāļĢāļāļāļēāļĢāļŦāļāļķāđāļāļāļēāļāļēāļĢāļĒāđāļŦāļāļķāđāļāļāļĨāļāļēāļ āļāļĢāļ°āļāļģāļāļĩ 254
Computational molecular modeling of chitin and chitosan
āđāļāļĢāļāļāļēāļĢāļŦāļāļķāđāļāļāļēāļāļēāļĢāļĒāđāļŦāļāļķāđāļāļāļĨāļāļēāļ āļāļĢāļ°āļāļģāļāļĩ 254
Solid polymer electrolytes based on nanocomposites of polyethylene oxide/sodium thiocyanate/montmorillonite, respectively
āđāļāļĢāļāļāļēāļĢāļŦāļāļķāđāļāļāļēāļāļēāļĢāļĒāđāļŦāļāļķāđāļāļāļĨāļāļēāļ āļāļĢāļ°āļāļģāļāļĩ 254
Structure formation in the crystallization and annealing of tetracontane nanoparticles
āļāļĨāļāļēāļāļ§āļīāļāļēāļāļēāļĢāļāļāļēāļāļēāļĢāļĒāđāļĄāļŦāļēāļ§āļīāļāļĒāļēāļĨāļąāļĒāđāļāļāđāļāđāļĨāļĒāļĩāļŠāļļāļĢāļāļēāļĢ