| abstract |
The invention provides compounds having the formula: n wherein R f is C n F 2n+1 —(CH 2 ) m —, wherein n is 1 to 22 and m is 0, or an integer from 1 to 3; X is —CO 2 —, —SO 3 —, —CONH—, —O—, —S— a covalent bond, —SO 2 NR—, or —NR—, wherein R is H or C 1 to C 5 alkylene; Y is —CH 2 — wherein z is 0 or 1; and R 1 is H, lower alkyl or R f —X—Y z — with the provisos that when X is —S—, or —O—, m is 0, sand z is 0, n is ≧7 and when X is a covalent bond, m or z is at least 1, and uses thereof. |