(255h) Interactions in Zeolite-Polymer Composites

Interactions in Zeolite-Polymer
Composites

Çigdem Atalay-Oral, Þafak Bora, Melkon Tatlier, Department of Chemical Engineering, Istanbul
Technical University,Maslak, 34469 Istanbul, Turkey

The preparation of
composite materials containing zeolite has already attracted interest for a few
applications. Polymer-zeolite mixed matrix membranes were obtained by
dispersion of zeolite crystals in polymeric films for use in gas separation and
pervaporation. The quality of the interface between zeolite crystals and
polymer are key points in related research studies [1]. A few studies also
exist concerning the preparation of composite zeolite coatings. Layers of low
and high silica zeolites were grown on aluminium substrates [2]. Zeolite coatings prepared on stainless steel
were covered by polyacrylic acid [3]. An interesting observation was that composite
samples desorbed somewhat higher amounts of water compared to both pure zeolite
and pure polyacrylic acid coatings. In this study, the presence of interactions
was investigated for different zeolite-polymer and zeolite-zeolite composite
coatings.

Zeolite coatings were prepared on stainless steel by
using the substrate heating method. Some of the coatings were covered by various
polymers, such as polyvinyl acetate, polyvinyl alcohol and cellulose acetate. Composite
zeolite A, X, P coatings were prepared by applying two consecutive syntheses,
to form two layers of different zeolite types. The coatings were characterized
by X-ray diffraction
(XRD), atomic force microscopy (AFM), scanning electron microscopy (SEM) and thermogravimetry (TG). It was observed that when the zeolite coatings were covered by polymer, they
exhibited water desorption of about 0.13-0.15 g/g sample which was higher than
the amount of water desorbed from both pure zeolite (0.12-0.14 g/g sample) and
pure polymer (0.038-0.083 g/g sample) under the operating conditions. The interactions between the polymer and
zeolite phases seemed to be mainly reponsible for this favorable effect. It
was possible to prepare composite zeolite coatings with different amounts of
zeolite A, X and P phases. TG analyses revealed the adsorption/desorption
capacities of the composites without significant interactions.

References

[1]   
Erdem-Þenatalar, M. Tatlier, Þ.B.
Tantekin-Ersolmaz, Stud. Surf. Sci. Catal. 135 (2001) 3089.

[2]   
R. Munoz, D. Beving, Y. Mao, Y. Yan, Micropor. Mesopor. Mater. 86 (2005) 243.

[3]   
A. Atakan, Ç. Atalay-Oral, M. Tatlier, T.
Erciyes, A. Erdem-Þenatalar, Micropor. Mesopor. Mater.  

   156 (2012) 262.