Copolymers of isobutyl maleate-divinylbenzene in the form of microspheres were obtained. In their preparation, the following techniques of heterogeneous polymerization were used: emulsion, modified emulsion, precipitation, suspension, and multistep swelling polymerization. Among the obtained microspheres, those synthesized by modified emulsion and multistep swelling polymerizations have a size suitable for HPLC purposes, whereas the product of suspension polymerization can be used as packing material for gas chromatography. Their porous structure was studied in detail. The influence of the polymerization technique on the particle size and morphology is discussed. (C) 2003 Wiley Periodicals, Inc.