A promising new strategy for fabricating polymer nanoparticles that are grafted with hydroxyl-functionalized phosphonium-based ionic liquid (PNPs-HPIL) through copolymerization of EGDMA and HPIL was established. The PNPs-HPIL catalyst exhibits good catalytic activity for the synthesis of cyclic carbonates through cycloaddition of CO2 to epoxides. At a catalyst loading as low as 0.47 mmol%, the PC yield is above 96.0% and PC selectivity almost 100%. It is noted that the hydroxyl groups of PNPs-HPIL play an important role for facilitating the cycloaddition reaction through the hydrogen bonding between hydroxyl groups and epoxides. Furthermore, the PNPs-HPIL catalyst shows good stability and reusability, which are beneficial to practical application in industry. (C) 2016 Elsevier B.V. All rights reserved.