We studied the effects of humic substances (HS) on the sorption of Fe(II) onto Al-oxide and clay sorbents at pH 7.5 with a combination of batch kinetic experiments and synchrotron Fe K-edge EXAFS analyses. Fe(II) sorption was monitored over the course of 4 months in anoxic clay and Al-oxide suspensions amended with variable HS types (humic acid, HA; or fulvic acid, FA) and levels (0, 1, and 4 w...

The demand for robust hydrogels in pharmaceutical, biomedical, and industrial applications has motivated intense research efforts in these wet polymeric materials. Recent advances have resulted in different strategies for creating highly stretchable polymeric hydrogels, including sliding-ring gels (SR gels), nanocomposite gels (NC gels), doublenetwork gels (DN gels), macromolecular microsphere ...

Three different protocols for the preparation of polymer layered silicate nanocomposites based upon a tri-functional epoxy resin, triglycidyl para-amino phenol (TGAP), have been compared in respect of the cure kinetics, the nanostructure and their mechanical properties. The three preparation procedures involve 2 wt% and 5 wt% of organically modified montmorillonite (MMT), and are: isothermal cu...

Partially exfoliated poly (methyl methacrylate) (PMMA) / montmorillonite clay nanocomposite was synthesized via the free radical polymerization of MMA in the presence of alkyl ammonium substituted polysilsesquioxane surfactant-modified clay and AIBN initiator in supercritical CO2. MMT clay was initially cation exchanged with the surfactant to enhance its hydrophobicity and to expand the interla...

introduction: nanocomposites are prepared by introduction of dispersed nanoscale particles into the polymer matrix based on four methods: template synthesis (sol-gel preparation); intercalation of polymer; and in situ intercalative polymerization and last one is melt blending, the most favorable and practical method due to its simplest, economical and environmentally friendly technic. this meth...

Polymer-nanoclay composite materials have attracted considerable interest among materials scientists recently because of the pioneering work carried out by a research group in the Toyota Central Research Laboratories. The group applied a nylon-montmorillonite clay nanocomposite as an under-the-hood structural part in the engine compartment of an automobile with significantly improved tensile st...

Montmorillonite/poly(vinyl alcohol) (MMT/PVA) nanocomposites spanning the complete range of MMT content (0-100 wt%) are prepared by simple evaporation-induced assembly. Effects of MMT content on the structure and mechanical properties of nanocomposites are systematically investigated and exhibit two important transitions at MMT contents of 30 wt% and 70 wt%. In the range of 0-30 wt%, the nanoco...

Finite difference method (FDM) has been adapted herein to analyze the performance of fully saturated clay barrier by using 1-D contaminant transport model to predict migration of two typical contaminant species, namely, sodium and chloride from the leachate of municipal waste landfill. The constructed clay liner media compacted in different lifts or the natural clay deposit beneath the landfill...