Process for the production of silane-crosslinked polyolefin in the presence of non-tin catalyst and resulting crosslinked polyolefin

A process for producing a silane-crosslinked polyolefin which comprises exposing a polyolefin containing at least one [1,3,2]-dioxasilinane ring structure to moisture in the presence of an organic carboxylic acid used as hydrolysis and condensation catalyst which does not contain tin, thereby producing the silane-crosslinked polyolefin, wherein the polyolefin contains at least one [1,3,2]-dioxasilinane ring structure and is made by the process of grafting an olefinically unsaturated [1,3,2]-dioxasilinane to a polyolefin in the presence of a free radical initiator, wherein the olefinically unsaturated [1,3,2]-dioxasilinane is given by general Formula (I):

• where R1 is a straight chain or branched alkyl group of from 1 to 6 carbon atoms or hydrogen;
• R2 is a straight chain or branched alkyl group of from 1 to 6 carbon atoms or a cycloalkyl group of from 5 to 8 carbon atoms;
• each occurrence of R3 is hydrogen;
• X1 is
• wherein R1 is a straight chain or branched alkyl group of from 1 to 6 carbon atoms or hydrogen, R2 is a straight chain or branched alkyl group of from 1 to 6 carbon atoms or a cycloalkyl group of from 5 to 8 carbon atoms, and each occurrence of R3 is hydrogen and the organic carboxylic acid is at least one organic carboxylic acid having general Formula (III):
• wherein G is a monovalent or polyvalent hydrocarbon containing up to 28 carbon atoms selected from the group consisting of alkyl, cycloalkyl, alkenyl, cycloalkenyl, aryl, aralkyl and arenyl;
• and the subscripts a and b are independently integers wherein a is 0 or 1 and b is 1 to 3.