The RAFT-Mediated Synthesis of Poly(styrene-co-maleic acid) through Direct Copolymerization of Maleic Acid

This work describes the reversible addition-fragmentation chain-transfer (RAFT)-mediated synthesis of poly-(styrene-co-maleic acid) (SMA). Various comonomer feeds were investigated to acquire tunable nonalternating SMA. The isolated copolymer constituted unique triad distributions, affording dissimilar physical properties compared to those of commercially available alternatives (SMA2000). The solubilization of synthetic DMPC and POPC lipid vesicles, using copolymers with variable composition, was investigated to elucidate the effect of triad distribution on SMA lipid particle (SMALP) formation. It was revealed that copolymers with similar overall amphiphilicity (composition of hydrophobic and hydrophilic repeat units in the copolymer) exhibit dissimilar interactions with a lipid bilayer as a result of different comonomer triad distributions, i.e., SSS, SSM, and MSS, and MSM triads. This work emphasizes the importance of the distribution of hydrophobic and hydrophilic comonomer units along the SMA backbone.