Patent ID: 8207245

Claim:
A chemical gel comprising at least one silicon-containing biostable polymer having monomers with an average functionality in the range of from 2.05 to 3.5 in which the biostable polymer is a polyurethane or polyurethane urea which is a reaction product of: (a) at least one silicon-containing polyol or polyamine having 2 or more functional groups in which the silicon-containing polyol or polyamine is a compound of formula (II) in which R 1 is selected from C 1-6 alkylene optionally substituted with OH or NR′R″ in which R′ and R″ are independently selected from H, CO 2 H and C 1-6 alkyl; R 9 is C 1-4 alkyl; R 10 is optionally substituted C 1-4 alkyl or in which R 1 and R 9 are as defined above; x is 5 to 30; y is 1 to 10; and n is 1 to 10; (b) a polyisocyanate; and (c) at least one non-silicon containing compound selected from a polycarbonate or a C 1-6 alkane having 1 or more functional groups selected from OH, NR′R″ in which R′ and R″ are the same or different and selected from H, CO 2 H and C 1-6 alkyl; wherein the gel has an NCO/OH or NH 2 ratio less than 1.