Temperature-stable anion-exchange materials from cyclopolymerization of quaternary ammonium halides

The preparation of quaternary ammonium salts containing allyl and methallyl groups from dimethylamine and pyrrolidine, and the free-radical initiated cyclopolymerization of these salts is described. It is shown by NMR analysis that poly(ammonium salts) are formed consisting of pyrrolidinium and azoniaspiro[4.4]nonane containing repeating units respectively with one or even two adjacent quaternary carbon centers along the chain. The ability to polymerize decreased from diallyl over allylmethallyl to dimethallyl monomers. Already polymers from diallylammonium salts showed sufficient stability in alkaline medium at 80 °C over a period of 168 h and for additional 18 h at 120 °C.