Gelation in the copolymerization of tetraallylammonium chloride with diallyldimethylammonium chloride and diallylammonium chloride

Abstract

Tetraallylammonium chloride (TAAC) was radically copolymerized with diallyldimethylammonium chloride (DADMAC) in water at 60°C. Gelation was delayed with an increase in the mole fraction of DADMAC in the monomer mixture. The precopolymer was easily incorporated into the gel at an initial stage of gelation, but a small amount of sol remained even at a late stage. The primary chain length increased with increasing DADMAC feed composition, while the discrepancy between the actual gel point and the theoretical one showed the opposite tendency, i.e. decreased. The swelling ratios of the resulting hydrogels were almost independent of the monomer composition up to 70mol% of DADMAC. TAAC was then copolymerized with diallylammonium chloride; the actual gel points were compared with the theoretical ones and the swelling ratios of the resulting gels were observed. These results are discussed mainly in terms of the steric effect on intermolecular and intramolecular crosslinks arising from the bulkiness of both growing polymer radical and polymer chain having unreacted pendant double bonds.