The use of reactions between polycarbonate (PC) and polystyrene-block-poly(ethylene-butylene)-block-polystyrene-grafted-maleic anhydride (SEBS-g-MAH) is a convenient way to create SEBS-g-PC. Grafting was realized by reactive extrusion at three temperatures using SnOct(2) or TBD catalysts. SEC analyses showed the apparition of a double distribution when the TBD was used. The mean residence time widely increased when this catalyst was used, and the rheological curves depicted a percolation effect of the SEBS nodules in the PC matrix. No explicit evolution was found with the use of SnOct(2). The thermal analyses showed the disappearance of the PC phase transition temperature. The Van Gurp-Palmen plots confirmed the efficiency of the TBD catalyst and that 260 degrees C was the optimal reactive extrusion temperature. (C) 2013 Society of Plastics Engineers