Supermacroporous polymer monolith prepared with polymeric porogens via viscoelastic phase separation for capillary electrochromatography

• Supermacroporous polymer monoliths containing the pore size of 5–10 μm were developed.
• Using polystyrene (PS) as polymeric porogens, acrylate-based monoliths were prepared for CEC separation.
• The dimensions of supermacropores can be tuned by varying the content of co-porogens and PS.
• The molecular weight of PS was also found to affect the pore size of the supermacropore monolith.

Supermacroporous poly(methacrylic acid-butyl methacrylate-ethylene glycol dimethacrylate) monoliths with the pore size up to 5–10 μm were successfully prepared in a ternary polymeric porogens utilizing viscoelastic effect. High concentration (over 20 mg/mL) of polystyrene (PS) in porogen was used to achieve the desirable characteristics of the monolithic capillary. Modification of the co-porogen composition, i.e., the content of dimethyl sulfoxide and isooctane, enabled tailoring of the supermacropore structure with a wide range of pore size. The effects of the amount of polymer porogen and molecular weights of PS on the formation of supermacropore were also studied. In preliminary applications, the separations of alkyl phenones and alkylbenzenes were achieved on the supermacropore columns using a mode of capillary electrochromatography. The study demonstrated successfully the ability of polymer porogen to form supermacropore monolith via viscoelastic phase separation