Novel nonionic surfactants based on sulfoxides. 2. Homo- and copolymers

The synthesis of new nonionic amphiphilic polymers of the polysoap type is described, as well as their general behaviour in aqueous solution. The polymers were prepared by homopolymerisation of acrylate polymerisable surfactants (or "surfmers"), which bear the nonionic sulfoxide moiety. Alternatively, small hydrophilic acrylate and acrylamide monomers bearing the nonionic sulfoxide moiety were copolymerised with dodecylacrylate and N-dodecyl- N-methylacrylamide. Compared to many other nonionic hydrophilic fragments, a single sulfoxide group behaves as a strongly hydrophilic fragment of small volume. However, its relative hydrophilicity depends sensitively on its precise positioning in the polymers. Properly placed, three sulfoxide groups can balance up to two dodecyl chains to obtain still water-soluble polymers that exhibit typical polysoap properties. Some of the new nonionic polymers show lyotropic liquid-crystalline behaviour at ambient temperature.