Silicone-containing macromonomers and low water materials

A medical device formed from a low water composition which is the polymerization product of a mixture comprising:

• (A) a macromonomer of the general Formula (I):
• (X)(E).sub.n (I)
• wherein:
• X is derived from a copolymer prepared by reacting the following components:
• (a) at least 50 mole % of an ethylenically unsaturated silicon-containing monomer,
• (b) 2.5 to 20 mole % of an ethylenically unsaturated monomer containing a hydroxyl, amino or carboxylic acid radical,
• (c) 0 to 15 mole % of an ethylenically unsaturated monomer other than monomers (a) or (b),
• (d) 2.5 to 20 mole % of a chain transfer agent, and
• the mole percent of components (a), (b), (c) and (d) being based on the total amount of said components;
• E is a polymerizable, ethylenically unsaturated radical;
• n is at least 2;
• and
• (B) an ethylenically unsaturated silicone-containing monomer other than the macromonomer of Formula (I).

A macromonomer useful in the preparation of a low water polymeric silicone composition consisting of the following Formula (Ia):

• (X)(E).sub.n (Ia)
• wherein:
• X is derived from a copolymer prepared by reacting the following components:
• (a) at least 80 mole % of an ethylenically unsaturated silicon-containing monomer,
• (b) 2.5 to 20 mole % of an ethylenically unsaturated monomer containing an active hydrogen atom,
• (c) 0 to 15 mole % of an ethylenically unsaturated monomer other than monomers (a) or (b), and
• (d) 2.5 to 20 mole % of a chain transfer agent,
• the weight percent of components (a), (b), (c) and (d) being based on the total amount of said components;
• E is a polymerizable, ethylenically unsaturated radical;
• and
• n is at least 2;
• wherein the low water polymeric silicone composition when cured absorbs maximumly 5% or less of water base on the total weight of the polymeric silicone and water.