In a previous study, we synthesized crosslinked P(TMGA-co-MBA) via an inverse suspension copolymerization of 1,1,3,3-tetramethylguandium acrylate (TMGA) and N,N'-methylenebisacrylamide (MBA) and found that the product is a good SO2 sorbent. However, the polymerization stability appeared to be poor under some reaction conditions and is far from being elucidated. In this study, the inverse suspension copolymerization was carried out using cyclohexane as solvent, Span60 as dispersant, and ammonium persulfate (APS) as initiator. The effects of the reaction conditions such as stirring speed, dispersant concentration, and temperature on the polymerization stability and particle size were systematically examined. It is found that the polymerization stability is a strong function of these parameters. Stable crosslinked poly(TMGA-co-MBA) particles from micrometer to millimeter diameters were synthesized under optimized conditions. (C) 2010 Wiley Periodicals, Inc. J Appl Polym Sci 118: 1450-1454, 2010