A composition, suitable for use in producing hydrogel polymer films from which biomedical devices such as contact lenses can be made, comprising at least one hydrophilic silicone macromer. In one aspect, a hydrophilic silicone macromer is of the Formula 1: X&mdashSi(R1)(R2)O&mdash(Si(R3)(R4)O)a&mdashSi(R5)(R6)&mdashY &emsp&emsp(1) wherein R1, R2, R3 R4, R5 and R6 are independently selected from a monovalent linear, branched, or cyclic radical with 1 to 50 carbon atoms, that can optionally contain a heteroatom or I I is RL-RP Y is a free radical polymerization-effective hydrophilic group with the general structure:RL-RP&mdashZ RL is a linking residue from a non-isomerizable hydrosilylation effective terminal olefin comprising the general structure &mdashCH2&mdashC(RbR7)&mdash(CR8R9)m, the subscript n is selected from integers from 1 to 10 R7, R8, and R9 can be selected from hydrogen and a mono-valent hydrocarbon radical with 1 to 10 carbon atoms that optionally contain a heteroatom Rb is selected from a monovalent hydrocarbon radical with 1 to 6 carbon atoms RP is a spacer group comprising a diavelant hydrophilic organic radical with 0 to 100 carbon atoms and optionally contains heteroatoms, and X is a free radical polymerizable group. The said composition can be polymers and films suitable for use in making contact lenses.
