Introduction

Polymer adsorbents included macroporous and hypercrosslinked copolymers. Polymer adsorbents are synthesized by two methods: (i) suspension polymerization and (ii) by post-crosslinking of polymers. As early as 1963 Millar and coworkers1 described the preparation of the macroporous

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styrene-divinylbenzene copolymer and the criterion of macroporosity: uptake of the non-swelling solvent greater than 0.1 mL/g and opalescence of beads. It was supposed that macroporous copolymers crosslinked to a high degree are rigid systems, in which swelling changes, are almost imperceptible. Such copolymers for adsorption applications were produced as marks Amberlite XAD-2 and Amberlite XAD-4. Later also adsorbents based on methacrylate macroporous copolymers for chromatographic applications under a mark Porapak and Chromaton were produced. These adsorbents were prepared by suspension polymerization. Hypercrosslinked polymer adsorbents were obtained by post-crosslinking of linear polystyrene2 or its macroporous3 copolymers in the swollen state by Friedel-Crafts reaction. Such adsorbents are produced by Purolite International UK (Hypersol-Macronet, MN-series), Bayer AG Germany (Lewatit VP OC 1163, Lewatit S 7768) Dow Chemical USA (Optipore) and Jiangsu A & G Environmental Technology Co Ltd China (NG-99, NG-100).

The polymer adsorbents found application in gas4'5 and liquid chromatography, adsorption of organic compounds from gas as so as from water phase. The new application consists in membrane technologies and in storage of gases. Macroporous and hypercrosslinked adsorbents were used as fillers in polymer membranes,6,7 on which separation of gases and small organic molecules was occurred. Hypercrosslined polymer adsorbents with high values of specific surface area were tested for reversible hydrogen storage.8 In the past we determine the sorption of organic compounds with macroporous9, 10 and hypercroslinked11 polymers.

In this paper we show the presence of polar adsorbate-adsorbent interaction on functionalized polymer adsorbent and increasing effect of nonpolar interaction on macroporous and especially hypercrosslinked adsorbents with high values of specific surface area.

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