Novel gelling structures based on polymer/surfactant systems

a high-molecular-weight version of PQ-10 is used in combination with SDS. Gels are viscoelastic materials, i.e., possess both liquid and solid characteristics and are most appropriately characterized by oscillatory rheology measurements that yield such parameters as storage modulus (G'), loss modulus (G"), phase angle (8), and so on. Measurements, with data analysis, were carried out using the Bohlin VOR Rheometer. The results are interpreted in terms of the formation of "super" macromolecules through association of the alkyl groups of surfactant molecules bound to the ionic sites of different polymeric molecules by strong electrostatic forces. It is shown that strong gels can be formed at quite low levels of polymer (--1%) and that there is an optimal level of SDS and other anionic surfactants to achieve maximum gel strength. Adjustment of the gel's properties, including liquefaction, can be achieved by suitable adjustment of the surfactant/polymer ratio or the addition of selected cationic materials. Preliminary information relevant to formulation is provided.