"oro alkyl groups preferably having at least about 8 carbon atoms and said aryl-perfluoroalkyl groups preferably having at least about 10 carbon atoms, R2, R3, R4, R5, and R6 each, independently of the others, is a methyl group or a hydroxyethyl group, m is an integer representing the number of repeating (???CH2???) units, and is from about 2 to about 6, p is an integer representing the number of r" . . . .