Conformational mechanisms of hydrophobically modified polymers and polymer/surfactant systems in solutions and at solid-liquid interfaces.

摘要

Hydrophobically modified water soluble polymers constitute a novel class of polymers that are finding important applications in detergency, mineral separation, pharmaceuticals, rheological control, enhanced oil recovery, paint and coating, etc. owing to their unique structural combination of both surfactants and polyelectrolytes. Comparing to conventional polyelectrolytes, hydrophobically modified polymers possess not only polar functional groups but also a considerable hydrophobic moiety---often present as hydrocarbon side groups. For this reason they form hydrophobic or hydrophilic aggregates depending upon the environment in a similar way as surfactant does, but differing with respect to the size, shape and hydrophobicity of the internal core, etc. This unique property together with the conformational sensitivity to pH, ionic strength, temperature, etc., gains HM polymers additional importance in drug delivery, rheological control, waste water treatment, and so on. However, a systematic investigation or a thorough understanding of the properties of these polymers is lacking. In the current work, the solution and solid/liquid interfacial properties of poly (maleic acid/octyl vinyl ether) (PMAOVE) and poly (maleic acid/methyl vinyl ether) (PMAMVE) have been systematically studied regarding hydrophobic aggregation, adsorption on solids, effect on colloid stability, and their complexation with various surfactants using multi pronged techniques.; By carrying out a systematic experimental study as well as stoichiometric calculations, the structure-conformation relationship of representative HM polymers, the current research provides a deep insight into the factors governing the properties of hydrophobically modified polymers. (Abstract shortened by UMI.)