Polymer-supported quaternary ammonium salts were prepared, and their applications as phase-transfer catalysts in aqueous organic systems were investigated. The polymer-bound phase-transfer catalysts were prepared with polystyrene resins crosslinked with the bifunctional monomers divinylbenzene and 1.4-butanediol dimethacrylate. The polymers were functionalized with chloromethyl groups and quaternized with trialkylamines having different alkyl chains. The obtained phase-transfer catalysts were characterized with IR spectroscopy and elemental analysis. The thermal stability was also determined by the thermogravimetric method. The catalytic properties of the phase-transfer catalysts were studied in halogen-exchange reactions. The effects of the nature and extent of crosslinking of the polymer support, the alkyl groups of the trialkylamine, and the reaction conditions were investigated. (C) 2009 Wiley Periodicals, Inc. J Appl Polym Sci 112: 2750-2756, 2009