Characterization of macroporous 1-vinyl-2-pyrrolidone copolymers obtained by suspension polymerization

Radical suspension copolymerization of 1-vinyl-2-pyrrolidone (VP) with three different cross-linkers: divinylbenzene (DVB), trimethylolpropane trimethacrylate (TRIM), and di(methacryloxymethyl) naphthalene (DMN) was used to prepare macroporous microspheres. During the copolymerization, the mixture of toluene and n-dodecane as a pore-forming diluent was used. All samples were characterized in terms of particle size and distribution, nitrogen content, specific surface area total pore volume, and pore size distribution. It was found that specific surface area of the obtained beads is strongly dependent on the diluent system and the type of cross-linker and achieves value from 27 to 845 m(2)/g. To determine the influence of chemical structure of cross-linkers on the selectivity and polarity of the copolymers, inverse gas chromatography was applied. In addition, VPDVB and VPDMN copolymers were modified by sulfonation into cation-exchangers with cation exchange capacity equal 1.98 and 2.31 mmol/g, respectively. (C) 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2012