Role of organogel chemistry on rheology and microstructure of molecular gels rationalized by Hansen solubility parameters

Using a perfume oil as a liquid phase, we study the gelling performance of a series of cyclic dipeptides as well as the gelled oils' rheological properties and microstructure. After identifying suitable gelators for perfume oil, this work explores the gels' microstructure, elasticity, and syneresis as a function of the chemical nature of the gelator. A correlation is found between the hydrogen-bonding Hansen solubility parameter and the plateau storage modulus of the gelled oils. For a specific non-polar liquid phase, the gels are more elastic when the hydrogen bonding is stronger. By increasing the gel's elasticity, e.g., by using gelators with stronger non-covalent interactions and forming more resilient networks under shear, the tendency for syneresis is decreased. Overall, this work showed that the Hansen parameter approach can be used for the design of organogels and to tune their material properties for specific applications.

Automated summary

Using perfume oil as a liquid phase, this study investigates the gelling behavior, rheological properties, and microstructure of cyclic dipeptides-based gels. The correlation between hydrogen-bonding Hansen solubility parameter and the plateau storage modulus of the gelled oils is revealed. Stronger hydrogen bonding results in more elastic gels in a specific non-polar liquid phase, reducing the tendency for syneresis. The findings demonstrate the utility of the Hansen parameter approach for designing organogels with tailored material properties for specific applications.