Water-Soluble Copolymers .42. Cationic Polyelectrolytes of Acrylamide and 2-Acrylamido-2-Methylpropanetrimethylammonium Chloride

The new monomer 2-acrylamido-2-methylpropanetrimethylammonium chloride (AMPTAC, 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 C-13-NMR. The reactivity ratio product r1r2 was found to be 0.62. Molecular weights varied from 1.4 to 16.5 X 10(6) 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-degrees-C. Solution behavior was independent of pH in the range of 3 to 11, and temperature in the range of 25 to 60-degrees-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