• Membrane Journal
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• v.20 no.4
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• pp.290-296
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• 2010

Ethylene vinyl acetate (EVA-28)/Co-Al LDH nanocomposite membranes were prepared by solution intercalation using organically modified LDH. LDH was made organophilic by the intercalation of dodecyl sulfate (DS) anion in the interlayer. The prepared membranes were characterized using XRD, FT-IR and SEM. Gas permeability of EVA/LDH nanocomposite membranes with LDH content of 1, 3, and 5 w% was studied for $O_2$ and $CO_2$ at pressure of 3, 4, and 5 bar. The permeability of $O_2$ and $CO_2$ was minimum for nanocomposite membrane with 1 wt% LDH and increased with increasing LDH content, which is presumably due to aggregation of LDH filler. The selectivity of $CO_2$ for $O_2$ showed the maximum value at 1 wt% of LDH content and decreased thereafter.

• Membrane Journal
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• v.23 no.2
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• pp.151-158
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• 2013

The effect of layered double hydroxides (LDH) on the gas separation properties of ethylene vinyl acetate copolymer was investigated. Mg-Al LDH/EVA nanocomposite membranes were prepared from solution intercalation using organically modified LDH (DS-LDH). Dodecyl sulfate (DS)-LDH was obtained by the intercalation of DS anion in the interlayer. The nanocomposite structure has been elucidated by X-ray diffraction (XRD), Fourier transform infrared (FT-IR) spectroscopy and scanning electron microscopy (SEM). XRD pattern clearly shows that the DS-LDH layers are disorderly well dispersed in the EVA matrix. The maximum tensile strength and elongation of the LDH/EVA nanocomposite membrane were found with the LDH content 3 wt%. The thermal properties of nanocompostie membrane were enhanced by the incorporation of LDH in EVA matrix. Gas permeation of LDH/EVA nanocomposite membranes with LDH contents of 1, 3, 5 wt% was studied for $O_2$ and $CO_2$ single gases. The presence of 3 wt% LDH decreased $O_2$ permeability by up to 53% compared to the EVA membrane. In spite of barrier property of nanocomposite membrane, however, the gas permeability for $CO_2$ was increased due to its strong affinity with the residual OH groups on the LDH.