Properties of polyelectrolyte-stabilised dispersions. Polystyrene latices stabilised by poly(methyl methacrylate-co-glycidyl methacrylate)–g-poly(acrylic acid)

Abstract

Polystyrene latices stabilised by an adsorbed graft copolymer of poly(acrylic acid) flocculate on cooling in the presence of high concentrations of 1:1 electrolyte (> 1 mol dm^–3). Critical flocculation temperatures have been measured as a function of degree of ionisation, salt concentration and type and are shown to correlate well with the corresponding θ-temperatures for poly(acrylic acid). An analogy is drawn between stabilisation of colloids by polyelectrolytes and steric stabilisation by non-ionic polymers.