Nonionic Surfactant Phase Behavior

Gel formation can be a challenge for formulators working with nonionic surfactants. This video provides an overview on specific types of liquid-crystal phases that form and their impact on viscosity and gel persistence. The video also shares tips to help keep gels from forming.
Transcript:
One challenge that formulators can face when working with nonionic surfactants is the formation of gels, some of which can be persistent and difficult to dissolve.
Such gels can occur when liquid-crystal phases are formed during the mixing of surfactant and water. The specific types of phases that form can have a very large impact on viscosity and gel persistence.
Surfactant structure strongly affects its propensity to form liquid crystal phases. For example, two surfactants of similar HLB and cloud point, but of differing compositions, can display dramatically different gelling behaviors.
Gel formation is often temperature-dependent. Formulating at sufficiently high temperatures can help ensure that gels are not formed during processing.
To this end, gel curves are a convenient formulation tool for identifying appropriate processing temperatures. Such curves can be produced by systematically varying temperature and surfactant concentration in water.
Gellation is just one example of potential challenges faced by formulators. Turn to Stepan as your partner in solving formulation challenges to meet your needs.