The effect of solvent polarity on phase inversion process for emulsification of poly(phenylene oxide) (PPO) ionomer

The lightly sulfonated poly(phenylene oxide) (SPPO) ionomers in different ratio of DMSO (dimethyl sulfoxide)/trichloromethane mixing solvents were emulsified by adding water to form a series of waterborne microemulsions. The variations of conductivity, viscosity and surface tension of SPPO ionomer solution as well as the effect of the polarity of solvent systems on the phase inversion during the emulsification process were studied. The mechanism of phase inversion was proposed.