Synthesis, Characterization, and Unusual Surface Activity of a Series of Novel Architecture, Water-Dispersible Poly(fluorooxetane)s

A series of water-dispersible, surface-active poly(fluorinated oxetane)s was prepared by ring-opening polymerization of fluorinated oxetane monomers using Lewis acid catalysis. The fluorinated oxetane monomers are made by phase-transfer catalytic reaction of a fluorinated alcohol with 3-bromomethyl-3-methyloxetane. Water dispersibility was introduced by conversion of the diol-terminated α,ω-(dihydroxy)poly(fluorinated oxetanes) into diammonium salts of α,ω-sulfate esters. The poly(fluorinated oxetane) salts exhibit unusually low surface tensions for materials based on a pendant trifluoro- or pentafluoroalkyl group. At a critical micelle concentration of ∼10 - 5 mol/L (∼10 - 3 wt %), surface tensions of ∼20−30 mN/m are obtained. The novel architecture of the poly(fluorinated oxetane) salts is thought to be responsible for the anomalous surface activity.