Grafting density and pendant length are recognized as decisive roles in membrane performance; however, they are not easy to control in widely employed free radical grafting polymerization. Herein, methoxypolyethylene glycol (MPEG) brushes with predetermined chain lengths and grafting densities were prepared from hydrophobic macroporous polypropylene membrane (MPPM) by click chemistry. The grafting density of MPEG on the membrane rose with MPEG concentration and click reaction time, while with the decrease of pendent length. Under the same reaction conditions, the densities were 88.065, 13.116 and 7.070 chains/100 nm(2) for MPEG-200/600/1000, respectively. The normalized pure water flux through MPEG-200 modified membrane (grafting density of 9.250 chains/100 nm(2)) was 222.0, twice that through the pristine one. Pearson correlation analysis indicates that the longer the pendent length and the higher grafting density are, the lower the normalized water fluxes of BSA solution and tap water are, while the better antifouling characteristics are. (C) 2016 Elsevier BV. All rights reserved.