High-pressure electroosmotic pumps based on porous polymer monoliths

Electroosmotic pumps have been prepared using macroporous polymer monoliths with their pore surface grafted with the ionizable monomers 2-acrylamido-2-methyl-1-propanesulfonic acid and [2-(methacryloyloxy)ethyl]trimethyl ammonium chloride, respectively. The effects of critical parameters such as pore size of the monolith, percentage of ionizable moieties in the grafted layer, crosslinking density, and driving voltage on both flow rate and pressure have been quantified. Electroosmotic pumps fabricated from the grafted monoliths afforded pressures as high as 0.38 MPa and electric-field-specific flow rates of up to 0.41 ml/min, both at an applied potential of 50 V.