Narrowly Distributed Cationic Polyelectrolytes and Polycarbobetaines

Quaternization of poly(4-VP) with alkyl halides and reaction of poly(VBC) with various tertiary amines result in cationic polyelectrolytes with a variety of charge density and of the hydrophilic-hydrophobic ratio of 

They can serve as models for basic investigations of solution properties and interaction with oppositely charged matter leading to new structure-property relationships. A further advantage is the low PD supporting the precision of any measurement. 

The pH-dependent solution properties in aqueous systems and the interaction of the different charges of the molecules were measured by CE and charge titration at different pH. CE is an especially powerful tool for characterization of the behavior of polycarboxybetaines in solution [78, 79]. A 

For equal distance of the charged sites, for example with 39 (k =1) and 41 (R=Me), the electrophoretic mobility of the polymer containing N with sp2-hybridization is much lower, because of delocalization of the positive charge in the aromatic ring. 

Complexing betaines 39 and 40 with strong polyanions such as polystyre-nesulfonate sodium salt reduces intramolecular interaction and acid-base titration becomes possible [85]. In pure poly(4-VP) based polycarbobetaines only 10-15% of the carboxylic groups are titratable [64]. 

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