Anion exchange membranes were prepared from graft polymerization of 4‐vinylbenzyl chloride on low‐density polyethylene matrix and subsequent amination with trimethylamine solution. The graft polymerization was initiated by benzoyl peroxide instead of gamma ray radiation. The resulting membranes had insufficient anion exchange functional groups; however, this could be enhanced by adding 10% styrene to 4‐vinylbenzyl chloride in a graft polymerization reaction. Further addition of styrene resulted in a decrease of the ion exchange capacity of anion exchange membranes due to competition with 4‐vinylbenzyl chloride in graft polymerization onto polyethylene. These were evidenced by analytical titration, elemental analysis, infrared spectroscopy and 1H NMR. © 2019 Society of Chemical Industry