Polymerization and quaternization of 1‐(2‐diethylaminoethyl)‐4‐vinylbenzene: A new cationic polyelectrolyte

Diethylamination of 1,4‐divinylbenzene catalyzed by lithium diethylamide gave rise to 1‐(2‐diethylaminoethyl)‐4‐vinylbenzene (3), quantitatively. Subsequent quaternization of 3 with ethyl bromide gave a cationic monomer, 4‐vinylphenethyltriethylammonium bromide (7). High molecular weight polymers, poly[1‐{4‐[2‐(diethylamino)ethyl]phenyl}ethylene] (5) and poly[1‐{4‐[2‐(triethylammonio)ethyl]phenyl}ethylene bromide] (8), were prepared from 3 and 7, respectively, by using radical initiators, especially with redox‐type ones. Anionic polymerization of 3 was also carried out. The relationship between the polymerization condition and the stereoregularity of the polymer was studied by Carbon‐13 NMR spectroscopy. A polyion complex (10) was prepared from 8 in combination with poly(sodium 4‐vinylbenzenesulfonate) (9) to evaluate its properties as biomedical material.