Title

Water-soluble polymers .71. pH responsive behavior of terpolymers of sodium acrylate, acrylamide, and the zwitterionic monomer 4-(2-acrylamido-2-methylpropanedimethylammonio)butanoate

Document Type

Article

Publication Date

1-30-1997

Department

Polymers and High Performance Materials

Abstract

Terpolymers of sodium acrylate (NaA), acrylamide (AM), and the zwitterionic monomer 4-(2-acrylamido-2-methylpropanedimethylammonio) butanoate (AMPDAB) were prepared by the free radical polymerization in 0.5M NaBr aqueous solution using potassium persulfate as the initiator. The feed ratio of AMPDAB : NaA: AM was varied from 5 : 5 : 90 to 40 : 40 : 20 mol %, with the total monomer concentration held constant at 0.45M. Terpolymer compositions were determined by C-13 NMR. Molecular weights varied from 3.0 X 10(6) to 9.7 X 10(6) g/mol. All terpolymers were soluble in deionized water and salt solutions at all pH values. The dilute and semidilute solution behavior of the terpolymers was studied as a function of composition, pH, and added electrolytes. Polyelectrolyte behavior was observed for all terpolymers at pH 8.5, as evidenced by high viscosity values at low polymer concentrations and viscosity decrease in the presence of added electrolytes. The reduced viscosity as a function of decreasing pH exhibits a minimum as the terpolymer undergoes a polyanion/ polyzwitterion/polycation transition. Comparison of the solution behavior of the terpolymers to terpolymers of 3-(2-acrylamido-2-methylpropane dimethylammonio)-1-propane sulfonate (AMPDAPS), AM, and NaA (AADAPS series) as well as copolymers of AMPDAB and AM (AMPDAB series) have been made. (C) 1997 John Wiley & Sons, Inc.

Publication Title

JOURNAL OF POLYMER SCIENCE PART A-POLYMER CHEMISTRY

Volume

35

Issue

2

First Page

231

Last Page

242