Silicone oligomers and curable compositions containing same

Oligomers of the formula:whereineach R is selected individually from the group consisting of B, R1, -OR2, R3 and R4; B is an organosilyl functional group bridged to the Si atom of the siloxane oligomer backbone by an Si-C bond; each R1 is independently a saturated aliphatic hydrocarbon group of 1 to 16 carbon atoms; each R2 is independently a group as defined for R1, an aromatic hydrocarbon group or an acyl group; each R3 is independently a monovalent organic radical containing an aliphatically unsaturated hydrocarbon group and each R4 is a monovalent organic radical linked to the Si atom of the siloxane oligomer backbone by an Si-C bond, which does not include an aliphatically unsaturated hydrocarbon group and which has thereon one or more members of the group selected from aromatic hydrocarbon, ether, ester, carbamate, thioether, polysulfide, blocked mercaptan, amide, epoxy, cyano and oximato groups; andwith the provisos thatat least one quarter of all R groups are -OR2; either at least one silicon atom of the oligomer has an R3 group thereon or at least one R is a B, or both; if there is a group R3 which is a vinyl group, there is at least one other group which is a B group, an R3 group other than vinyl, or an R4 group; m=2 to 20; n=0 to 50; o=0 to 20; and p=0 to 10,are useful as coupling agents in curable compositions of filled organic polymers used for wire and cable insulation. The oligomers also have utility as crosslinkers, as adhesion promoters, to provide a dual radical/moisture cure mechanism, and/or to provide moisture resistance in coating, in other compositions, such as curable adhesives and coatings.