Sterically Crowded Anionic Polyelectrolytes with Tunable Charge Densities Based on Stilbene-Containing Copolymers

Anionic polyelectrolytes with various charge densities and a well-defined chain architecture have great industrial and fundamental importance. In this article, we describe the synthesis and characterization of new sterically crowded conformationally constrained anionic polyelectrolytes with tunable charge densities based on highly functionalized stilbene-maleic anhydride/maleimide comonomers. Polyelectrolyte precursors with tert-butyl carboxylate protecting groups are first prepared by radical polymerization and readily characterized by H-1 NMR, SEC, TGA, and DSC without the complications normally arising with charged macromolecules. The precursors are converted into their corresponding deblocked forms by simply reacting with trifluoroacetic acid to deprotect the tert-butyl group and then neutralized in basic aqueous solutions to yield anionic polyelectrolytes.