The effect of polymeric hydrocolloids on the partial coalescence of liquid drops at liquid-liquid interfaces

• Published in: Journal of colloid and interface science Vol. 33; no. 4; pp. 491 - 507
• Main Authors: Glass, J.E, Lundberg, R.D, Bailey, F.E
• Format: Journal Article
• Language: English
• Published: Elsevier Inc 01.01.1970
• ISSN: 0021-9797; 1095-7103
• DOI: 10.1016/0021-9797(70)90001-9

The coalescence behavior of organic drops at organic-aqueous hydrocolloid interfaces has been investigated. Synthetic water-soluble polymers of varying solution surface activity and molecular weight were employed as stabilizing agents for the organic drops. The number of steps required for complete coalescence of an organic drop, and the stability provided that drop, were a function of the hydrocolloid's molecular weight and solution surface tension. With weakly surface-active hydrocolloids, drop stability increased whereas the number of coalescence steps decreased with increasing polymer molecular weight. However, with strongly surface-active hydrocolloids greater drop stability was observed with lower molecular weight polymers. An aging phenomenon, which imparted stability, was noted with hydrocolloid increasing solution surface activity and decreasing molecular weight. This study, in general, relates stepwise coalescence and drop stability to the amount of hydrocolloid adsorbed and its interfacial reorientation capability. The results are believed to reflect the significance of a “dynamic interfacial viscosity parameter” in the coalescence phenomenon. In a related study, an attempt was made to examine the effect of poly(ethylene oxide) conformational changes on coalescence behavior. Copolymers of ethylene oxide and the effect of contraction in poly(ethylene oxide's) hydrodynamic volume, induced by interaction with inorganic salts, were examined. The significance of these studies is discussed.