Moisture-crosslinked polyolefin compositions

Moisture-crosslinkable polymer compositions and moisture-crosslinked articles prepared therefrom are prepared from a composition predominantly comprising an ethylene-based polyolefin and a propylene-based polyolefin, in which both the ethylene-based and propylene-based polyolefins are present in amounts of less than 50% by weight. The composition also includes hydrolysable silane groups, which may be grafted onto the ethylene-based polyolefin, or a blend of the ethylene-based and propylene-based polyolefins, in the presence of a free radical initiator. The moisture-crosslinked articles further comprise a silanol condensation catalyst to permit the silane groups to form crosslinks in the presence of moisture. After crosslinking, the article may be heated, stretched and then cooled to render it heat shrinkable.