Hydrophobically modified cationic polyelectrolytes

Cationic polyelectrolytes with hydrophilic/hydrophobic properties were synthesized by condensation polymerization of epichlorohydrin with dimethylamine, N,N-dimethyl-1,3-diaminopropane, and primary amines with nonpolar chains, hexyloxypropylamine and decyloxypropylamine. Viscometric measurements of these polymers in dilute aqueous solutions with and without salt revealed a typical polyelectrolyte behaviour. Thermal analyses of cationic polyelectrolytes showed that the relative thermal stability decreases with decreasing hydrophobic chain lengths and increasing quaternary ammonium salt group contents. The flocculating efficiency of these polycations on a suspension of montmorillonite was also studied. (C) 2000 Elsevier Science Ltd. All rights reserved.