Adsorption of Polyetheramines on Montmorillonite at High pH
Citations Over TimeTop 21% of 2010 papers
Abstract
Adsorption of a series of polyetheramines on montmorillonite in aqueous suspension was investigated by a range of methods: elemental analysis, atomic absorption spectroscopy, measurement of pH, conductivity and electrophoretic mobility, and small-angle X-ray scattering. Adsorption proceeds through an ion exchange mechanism. The maximum surface coverage attained is equivalent to about 40% of the cationic exchange capacity of the clay. Adsorption of the poly(oxypropylene) block adjacent to the amine group onto the clay surface may contribute to this. Surprisingly the adsorption takes place at pH conditions well above the pK(a) of the amine surfactants, where they are not protonated in the bulk solution. The surface coverage as a function of molar mass broadly agrees with predictions assuming adsorbed polymers adopt a densely packed mushroom configuration at the clay surface.
Related Papers
- → Protonation of homotroponeiron tricarbonyl and cyclooctatrienoneiron tricarbonyl complexes(1980)8 cited
- → 13C nuclear magnetic resonance study of the protonation of 2,2,4-trimethyl-1,5,9-triazacyclododecane(1988)6 cited
- Current Aspects of Organically Modified Montmorillonite(2006)
- → The effect of substitution on protonation sites: evidence for protonation at N(3) in N(7)-substituted adenine(1975)6 cited
- The Protonation Equili rium and Decomposition of Amino- and Hydroxyphosphonates, Phos phine Ox ides and Phosphonic Acid(2007)