(Cs H2s O), t is an integer of 1 to about 6, and p is an integer of 0 to about 4; Rf a is selected from the group consisting of --(Cx F2x O)z Cy F2y+1, --Cq F2q X', and --Cq F2q-2 X', where x is independently an integer of 1 to about 10 for each Cx F2x O group, y is an integer of 1 to about 10, z is an integer of 1 to about 10, q is an integer of 1 to about 20, and X' is selected from the group c