Laponite Dispersions in the Presence of an Associative Polymer

• Published in: Langmuir Vol. 18; no. 1; pp. 155 - 159
• Main Authors: Aubry, Thierry, Bossard, Frédéric, Moan, Michel
• Format: Journal Article
• Language: English
• Published: American Chemical Society 08-01-2002
• Subjects: Engineering Sciences
• ISSN: 0743-7463; 1520-5827
• DOI: 10.1021/la011032i

Sedimentation and viscometric properties of a dilute Laponite dispersion are studied in the presence of an associative polymer, hydrophobically modified (hydroxypropyl)guar, and its nonassociative precursor, focusing on the specific influence of intermolecular associations. The hydrophobic groups do not take a significant part in the adsorption process. The main difference between the associative and the nonassociative polymers appears at polymer concentrations above complete coverage of the clay mineral. In this concentration range and up to the overlap concentration, nonassociating macromolecules lead to the formation of freely suspended entities, whose size did not depend on the polymer concentration. The associating macromolecules, in the same concentration range, lead to aggregation of the particles, the degree of which depends on the polymer concentration. This behavior is attributed to the formation of associating junctions between adsorbed and/or nonadsorbed polymers.