Porous membranes built up from hydrophilic poly(ionic liquid)s
  Porous polymer membranes via electrostatic complexation triggered by neutralization are fabricated for the first time from a water-soluble poly(ionic liquid) (PIL). The porous structure is formed as a consequence of simultaneous phase separation of the PIL and ionic complexation, which occurred in a basic solution of a non-solvent for the PIL. These membranes have a stimuli-responsive porosity, with open and closed pores in isopropanol and in water, respectively. This property is quantitatively demonstrated in filtration experiments, where water is passing much slower through the membranes than isopropanol. 
Karoline T\"auber, Annett Zimathies, Jiayin Yuan
cond-mat.soft cond-mat.mtrl-sci