POLYETHYLENE OXIDE DOES NOT NECESSARILY AGGREGATE IN WATER

Polyethylene oxide (PEO) is one of the most extensively studied of all water-soluble synthetic polymers, both for its wide range of applications1-4 and from the fundamental standpoint of understanding the behaviour of polymer solutions. The aggregation behaviour of PEO in water and its consequences have been a matter of concern in many studies5-11 of this system. It is not clear, however, whether PEO aggregation is an inherent property of these aqueous solutions, although this knowledge can have important and widespread consequences for both industry and polymer science. Here we use dynamic light scattering from high-molecular-weight PEO in carefully purified water and in methanol to show unambiguously that both are good solvents in the sense that PEO behaves like a typical random coil in both, with no evidence of aggregation. © 1990 Nature Publishing Group.