ADSORPTION OF POLYAMPHOLYTES ON POLYSTYRENE LATEX - EFFECT ON COLLOID STABILITY

[摘要] The interfacial characteristics of low-charge-density polyelectrolytes and polyampholytes synthesized by a microemulsion polymerization technique have been investigated. Terpolymers of acrylamide (AM, neutral segment), [2-(methacryloyloxy)ethyl]trimethylammonium chloride (MADQUAT, positively charged segment), and sodium 2-(acrylamido)-2-methyl propanesulfonate (NaAMPS, negatively charged segment) and copolymers of AM and MADQUAT as well as of MADQUAT and NaAMPS were adsorbed on a negatively charged polystyrene latex. The zeta potential at full surface coverage was determined and analyzed as a function of the surface charge excess of the colloid-polymer complex. The domains of colloidal instability were determined and the rate of destabilization was studied for the different systems at the optimum flocculation concentration. A deviation from the usual polyelectrolyte behavior was found for the copolymers and the terpolymers, which may be attributed to the reversible character of the aggregation processes resulting from a progressive modification of the characteristics of the adsorbed layer. (C) 1995 Academic Press, Inc.

[发布日期] 1995-12-01

[关键词] POLYAMPHOLYTE ADSORPTION;COLLOID STABILIZATION BY POLYAMPHOLYTES;SURFACE CHARGE OF ADSORBED TERPOLYMERS