A commercial-grade LLDPE resin was cross-linked using three different dialkyl peroxides, at three different concentrations. The peroxides were ranked in order of their Cross-linking efficiency and their effectiveness at increasing the storage modulus of the virgin resin at the cure temperature. The chemical mechanism by which the cross-linking occurs is shown to be closely related to the changes in concentrations of reactive vinyl species on the polyethylene molecules, which follows well with proposed mechanisms of previous publications. Finally, a direct relationship is shown to exist between the rate of peroxide decomposition and the rate of increase in storage modulus of the rubbery modified resin during the curing reaction. © 1993 John Wiley & Sons, Inc.