Display omitted •The potential of modified polymethyl methacrylate to capture carbon dioxide was investigated.•Modified polymethyl methacrylate containing a triphenyltin moiety has the largest surface area.•The modified polymethyl methacrylate efficiently captured carbon dioxide. This study evaluates the potential of modified polymethyl methacrylate (PMMA) materials, which incorporate organotin moieties pendant on the polymeric chains, as media for carbon dioxide storage. The PMMA containing a triphenyltin moiety has the largest specific surface area (SBET=11.618 m2/g) in comparison to the polymers containing tributyl (5.287 m2/g) and trimethyl (4.881 m2/g) residues. The PMMA with the triphenyltin moiety proved to be the most efficient material in capturing carbon dioxide (34.8 cm3/cm, 6.8 wt%), which is attributed to its relatively high surface area and pore volume and diameter compared to the others.