A process to form a composition, said process comprising at least the following steps A) and B): A) mixing together at least the following components a and b to form a first composition: a) the anhydride-functionalized olefin-based polymer, and b) at least one multifunctional epoxy compound comprising at least two epoxy groups, or at least one oxetane compound comprising at least one oxetane group; B) exposing the first composition to moisture to form the crosslinked olefin-based polymer. Also, related is first compositions and crosslinked compositions.