The structure and properties of nanocomposites of poly(ethylene oxide), with Ag and Au nanoparticles, surface modified with a 1:1 (by volume) oleylamine/oleic acid mixture, were investigated via transmission electron microscopy, scanning electron microscopy, thermogravimetric analysis, differential scanning calorimetry (DSC), infrared spectroscopy, dynamic mechanical analysis, and static mechan...

This study investigates the feasibility of using ethylene oxide (EO) chain adsorption to determine the surface area of smectite in water. Experimental results indicate that high-molecular-weight poly(ethylene oxide) (PEO) should be used to provide reasonable estimations for monolayer capacity of PEO on smectite. The surface areas of smectites in water are calculated from the monolayer capacity ...

Block copolymer thin films with distinct morphologies are prepared by spin casting a nominally lamellar assay of poly(styrene-block-ethylene oxide) from a variety of solvents with and without salt doping. The 3-D morphologies of free-standing thin-film regions, which are obtained by casting directly onto holey substrates, are investigated in detail using various energy-filtering transmission el...

Chain exchange between block polymer micelles in highly selective solvents, such as water, is well-known to be arrested under quiescent conditions, yet this work demonstrates that simple agitation methods can induce rapid chain exchange in these solvents. Aqueous solutions containing either pure poly(butadiene-b-ethylene oxide) or pure poly(butadiene-b-ethylene oxide-d4) micelles were combined ...

The temperature-induced structural changes and thermodynamics of ionic microgels based on poly(acrylic acid) (PAA) networks bonded with poly(ethylene oxide)-b-poly(propylene oxide)-b-poly(ethylene oxide) (PEO-PPO-PEO) (Pluronic) copolymers have been studied by small-angle neutron scattering (SANS), ultra-small-angle neutron scattering (USANS), differential scanning calorimetry (DSC), and equili...

We fabricated a novel vascular endothelial growth factor (VEGF)-loaded poly(lactic-co-glycolic acid) (PLGA)-nanoparticles (NPs)-embedded thermo-sensitive hydrogel in porcine bladder acellular matrix allograft (BAMA) system, which is designed for achieving a sustained release of VEGF protein, and embedding the protein carrier into the BAMA. We identified and optimized various formulations and pr...

We exploited the viscoelasticity of biocompatible dilute polymeric solutions, namely, dilute poly(ethylene oxide) solutions, to significantly enhance mixing in microfluidic devices at a very small Reynolds number, i.e., Re approximately 0.023, but large Peclet and elasticity numbers. With an abrupt contraction microgeometry (8:1 contraction ratio), two different dilute poly(ethylene oxide) solu...

The crossover behavior of 50 000 molar mass poly~ethylene oxide!/methanol solutions from dilute solution to the melt/gel was examined. At first this behavior was investigated without LiClO4 and then reexamined with LiClO4 . To better understand this behavior, the dependencies of dynamic light scattering ~specifically, photon correlation spectroscopy! measurement results on polymer concentration...

We synthesized an amphiphilic coil-rod-coil triblock molecule consisting of hexa-p-phenylene as a rod block and poly(ethylene oxide) with the number of repeating units of 17 as coil blocks and investigated aggregation behavior in aqueous environment. The rod-coil molecule was observed to aggregate into discrete micelles consisting of hydrophobic disklike rod bundles encapsulated by hydrophilic ...