The aliphatic fluorocarbon terminal portion can be represented by the formula --D(Cx F2x O)z Cy F2y+1, where x is an integer of 1 to about 12 (preferably, 1 to about 8), y is an integer of 1 to about 12 (preferably, 1 to about 8), z is an integer of 1, and D is selected from the group defined above.