Morphological, transport, and adsorption properties of ethylene vinyl acetate/polyurethane/bentonite clay composites

作者：Dlamini Derrick S; Mishra Ajay K^*; Mamba Bhekie B

来源：Journal of Applied Polymer Science, 2012, 124(6): 4978-4985.

DOI：10.1002/app.35600

• adsorption
• crystallization
• microstructure
• phase behavior
• synthesis

The effect of polyurethane (PU) foam on the morphological and transport properties of ethylene vinyl acetate (EVA) with 9% vinyl acetate and the potential application of 3%bentonite/28.5% PU/68.5% EVA composites fabricated via the melt-blending method in heavy-metal extraction from water systems were investigated. EVA did not swell in water, whereas the PU/EVA blend attained a maximum percentage of deionized water uptake of 2.158 mol %. A 3% bentonite/28.5% PU/68.5% EVA composite blend successfully removed 90% of Pb2+ from an aqueous solution with an initial concentration of 30 mg/L, whereas 3% bentonite/97% EVA could only extract 7.323% of Pb2+ ions. Pb2+ adsorption was found to obey the Langmuir adsorption isotherm and pseudo-second-order kinetic model. Thermodynamic studies demonstrated that the adsorption was favorable at room temperature and the uptake of Pb2+ was mostly by physical adsorption, as also indicated by the value n = 2.449 (where n is an empirical parameter indicating transport mode) from the Freundlich adsorption isotherm.

• 出版日期2012-6-15