Water-soluble copolymers. XLII. Cationic polyelectrolytes of acrylamide and 2-acrylamido-2-methylpropanetrimethylammonium chloride

The new monomer 2-acrylamido-2-methylpropanetrimethylammonium chloride (AMP-TAC, M₂) has been synthesized. Free radical copolymerization with acrylamide (AM, M₁) in feed ratios varying from 10 to 50 mol % AMPTAC gave the cationic ATAM series. Copolymer compositions were determined from ¹³C-NMR. The reactivity ratio product r₁r₂ was found to be 0.62. Molecular weights varied from 1.4 to 16.5 × 10⁶ g/mol for the copolymers. Turbidimetric studies showed aqueous solutions of the copolymers to be phase stable in the presence of CaCl₂ and Na₂CO₃ up to 100°C. Solution behavior was independent of pH in the range of 3 to 11, and temperature in the range of 25 to 60°C. Intrinsic viscosities of the cationic copolymers decreased with the addition of electrolytes; however, some samples showed curvature in plots of intrinsic viscosity versus the inverse square root of ionic strength. © 1993 John Wiley & Sons, Inc.