TECHNOLOGY FOCUS - POLYMERS - Preparation (Disclosed): Preparing the polymer comprises: providing a starting polymer e.g. polystyrene; reacting the starting polymer with a nitrogen-containing or phosphorus-containing compound to produce anionic polymer; and reacting the ionic polymer with an acid e.g. sulfuric acid, to give the polymer. Preferred Components: The Bronsted-Lowry acid is sulfonic acid, phosphonic acid, acetic acid, isophthalic acid, boronic acid or perfluorinated acid. The Bronsted-Lowry acids are directly connected to the polymeric backbone. The Bronsted-Lowry acid is present at 0.1-20 mmol/g of polymer. The acidic monomers further comprise a linker connecting the Bronsted-Lowry acid to the polymeric backbone. The linker is optionally substituted alkylene, cycloalkylene, alkenylene, arylene, heteroarylene, alkylene ether, alkylene ester or alkylene carbamate. The nitrogen-containing cationic group is pyrrolium, imidazolium, pyrazolium, oxazolium, thiazolium, pyridinium, pyrimidinium, pyrazinium, pyradizinium, thiazinium, morpholinium, piperidinium, piperazinium or pyrrolidinium. The phosphorus-containing cationic group is triphenyl phosphonium, trimethyl phosphonium, triethyl phosphonium, tripropyl phosphonium, tributyl phosphonium, trichloro phosphonium or trifluoro phosphonium. The ionic monomers are directly connected to form the polymeric backbone. The ionic monomers further comprise the linker that connects the nitrogen-containing cationic group or the phosphorus-containing cationic group to the polymeric backbone. The polymeric backbone is polyethylene, polypropylene, polyvinyl alcohol, polystyrene, polyurethane, PVC, polyphenol-aldehyde, PTFE, polybutylene terephthalate, polycaprolactam, poly(acrylonitrile butadiene styrene), polyalkylene ammonium, polyalkylene diammonium, polyalkylene pyrrolium, polyalkylene imidazolium, polyalkylene pyrazolium, polyalkylene oxazolium, polyalkylene thiazolium, polyalkylene pyridinium, polyalkylene pyrimidinium, polyalkylene pyrazinium, polyalkylene pyradizinium, polyalkylene thiazinium, polyalkylene morpholinium, polyalkylene piperidinium, polyalkylene piperazinium, polyalkylene pyrrolidinium, polyalkylene triphenyl phosphonium, polyalkylene trimethyl phosphonium, polyalkylene triethyl phosphonium, polyalkylene tripropyl phosphonium, polyalkylene tributyl phosphonium, polyalkylene trichloro phosphonium, polyalkylene trifluoro phosphonium, or polyalkylene diazolium. The polymer is crosslinked, and further comprises: hydrophobic monomers connected to form the polymeric backbone, where each hydrophobic monomer comprises a hydrophobic group; acidic-ionic monomers connected to form the polymeric backbone, where each acidic-ionic monomer comprises a Bronsted-Lowry acid and a cationic group. EXAMPLE - Poly(styrene-co-3-methyl-1-(4-vinylbenzyl)-3H-imidazol-1-iumchloride-co-divinylbenzene) (63 g) was charged into a flask (500 ml) equipped with a magnetic stir bar and condenser. Cold concentrated sulfuric acid (300 ml) was gradually added into the flask under stirring which resulted in formation of dark-red colored slurry of resin. The slurry was stirred at 85 degrees C for 4 hours. After cooling to room temperature, the reaction mixture was filtered using fritted glass funnel under vacuum and then washed repeatedly with de-ionized water until the effluent was neutral, as determined by pH paper. The sulfonated resin beads were finally washed with ethanol and air dried to give poly(styrene-co-4-vinylbenzenesulfonic acid-co-3-methyl-1-(4-vinylbenzyl)-3H-imidazol-1-ium bisulfate-co-divinylbenzene). The chemical functionalization of the polymer resin with sulfonic acid groups was determined to be 1.6 mmol/g.