Copoly(ionic liquid)s (coPILs) based on poly(styrene)-co-poly(4-vinylbenzylbutylimidazolium) with different anions (Cl- and HCO3-), denoted as PS-co-PVBnBuImCl 1 and PS-co-PVBnBuImHCO(3) 2, were used as reactive polymers for the purpose of post-polymerization modification and organic catalysis. While coPIL 1 could be derived into the corresponding poly(N-heterocyclic carbene)-silver transition metal complex referred to as poly(NHC-Ag) by a simple deprotonation/metallation sequence utilizing Ag2O, coPIL 2 was found to quantitatively react with various electrophiles, including CS2, isothiocyanate and transition metals (based on Pd and Au) upon formal loss of "H2CO3, affording the post-functionalized poly(NHC-CS2), poly(NHC-isothiocyanate) and poly(NHC-Met) (Met = Au, Pd) copolymers. The catalytic activity of both coPILs 1 and 2 was also examined in cyclic carbonate formation by reaction between CO2 and propylene oxide and in the benzoin condensation, respectively. (C) 2014 Elsevier Ltd. All rights reserved.