Abstract: An improved process for crosslinking a polyolefin polymer is described. The process involves grafting a silane material onto the polyolefin based polymer in the presence of a free radical generating initiator material and then hydrolyzing the silane material to form crosslinks. By using an effective molar ratio of silane material to free radical of 40 or greater in the grafting reaction, premature crosslinking is controlled and the grafted polymer can be shaped first and then crosslinked. In another aspect of the invention, the crosslinking process is improved by adding a catalyst for the hydrolysis catalyst to the surface of a shaped article made from the grafted polymer. Grafted polymer and articles made from the grafted polymer, particularly fibers, are also disclosed.