Weakly acidic gases such as CO2, SO2, NO2, and NO discharged directly into the atmosphere have been suggested to contribute to the formation of acid rain and to global climate changes. In an effort to develop an effective process by which to remove these pollutants from gas streams, we synthesized polymeric sorbents that bind acid gases. In an earlier work, we reported that polymers carrying pendant amine groups are capable of absorbing carbon dioxide to form thermally reversible amine/CO2 addition products. In this study, we investigated the effects of amine structure on acid gas sorption and the thermal reversibility of the sorption-desorption reactions of various acid gases including CO2, SO2, NO, and NO2 with bot h linear and cross-linked polymers using thermogravimetric analysis.