ISSN:
0021-8995
Keywords:
Chemistry
;
Polymer and Materials Science
Source:
Wiley InterScience Backfile Collection 1832-2000
Topics:
Chemistry and Pharmacology
,
Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics
,
Physics
Notes:
Water-soluble, low charge density polyampholytes have been synthesized by free-radical terpolymerization of acrylamide (AM) with sodium 3-acrylamide-3-methylbutanoate (NaAMB) and 2-acrylamido-2-methylpropanetrimethylammonium chloride (AMPTAC). Terpolymer compositions obtained by 13C-NMR reflect monomer feed concentrations. Molecular weights and second virial coefficients range from 3.43 to 19.4 × 106g/mol and from 1.63 to 3.61 mL mol/g-2, respectively, as determined by low-angle laser light scattering. Ionic associations were explored by investigating the dilute solution properties as a function of terpolymer concentration, terpolymer charge density, and added electrolytes. Terpolymers with 0.5, 2.5, and 5.0 mol % of both of the cationic (AMTAC) and anionic (NaAMB) monomers were soluble in deionized water, whereas those with 10 and 15 mol % of each monomer required electrolyte addition. The higher-density terpolymers undergo a 700% increase in intrinsic viscosity upon changing NaCl concentration from 0.05 to 1M. Polyelectrolyte behavior could be induced by decreasing solution pH below the pKa of the NaAMB mer. Intermolecular ionic associations resulting in gel networks were studied utilizing dynamic mechanical analysis. © 1993 John Wiley & Sons, Inc.
Additional Material:
4 Ill.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1002/app.1993.070480617
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