Inverse gas chromatography (IGC) studies on the surface of polyethylene (PE) particles grafted with acrylic acid and acryl amide have been reported. Surface properties of the virgin and grafting-modified PE were compared by IGC. The dispersive contributions of the surface free energy gamma(d)(s) and the K-A and K-B parameters expressing the ability of the stationary phase to act as Lewis acid or Lewis base were calculated. The results showed that the gamma(d)(s) value increased significantly after grafting. The PE samples grafted with acrylic acid and acrylamide showed a predominantly basic character while the virgin PE was acidic. All of these suggested that the surface of PE has been modified through the grafting reaction, and thus is expected to improve its adhesions with other polymers. (c) 2008 Wiley Periodicals, Inc.