Synthesis of CO2-philic/hydrophilic surfactant with brush structure and its application in preparing monolithic materials

A new strategy was developed to build a CO 2 -philic/hydrophilic surfactant by combining the common free radical polymerization and the grafting modification technology, and a brush polymer was synthesized with poly(vinyl acetate)(PVAc) based copolymer as the CO 2 -philic group (as the main chain) and the methoxy poly(ethylene glycol) (mPEG) as the hydrophilic part (as the branched chain) (PVAc- g -mPEG). The CO 2 -philic ability can be controlled by adjusting the chain length of the CO 2 -philic fragment. The results indicate that PVAc- g -mPEG has excellent surfactant activity, and can emulsify the CO 2 /H 2 O system to obtain the CO 2 -in-water (C/W) high interval phase emulsion (HIPE 80%, v/v), which can remain stable for more than 20 h. If using the monomers/crosslinking agent solution instead of water, the highly porous monolithic materials will be obtained after the continuous phase is polymerized. In this paper, polyacrylamide (PAM) and poly(acrylamide/diethyl aminoethyl methacrylate) (PADM)-based porous monolithic materials were prepared. These materials were used to remove bovine serum albumin (BSA, as the model matter) from the solution, and the results indicated that PAM-based porous monolithic materials had almost no enrichment capacity for protein, while PADM-based porous monolithic materials can adsorb BSA up to 129.3 mg/g.