No abstract

The effect of chain branching on glycolipid thermotropic and lyotropic phases was investigated for a series of synthetic β-D-glucosides derived from Guerbet alcohols, whose total hydrocarbon chain length ranged from C 8 to C 24 . The compounds, which can be viewed as isosteric mimics for glycoglycerolipids, were synthesised in high purity and their liquid crystalline phases were studied using optical polarising microscopy (OPM), and small-angle X-ray diffraction. When dry, the shortest compound (total C 8 ) exhibits a monotropic L α phase while longer ones (C 16 and C 20 ) adopt inverse hexagonal H II phases. The C 24 compound forms an ordered lamellar phase at room temperature, but exhibits a metastable H II phase upon cooling. Curiously the intermediate chain length homologue (C 12 ) adopts an isotropic inverse micellar (L 2 ) phase in the dry state over the range of temperatures studied. Upon hydration, the C 8 compound dissolves, and the C 12 compound forms a fluid lamellar L α phase. The C 16 Guerbet glucoside (i.e. β-Glc-C 10 C 6 ) exhibits an inverse bicontinuous cubic phase of space group Ia3d in excess water, never previously observed in branched-chain lipids, and very seldom observed in excess water. The C 20 compound remains in the H II phase upon hydrating, with the lattice parameter swelling substantially.

Factors that improved the biodegradation of surfactants have successfully used to prepare higher ordered biodegradable tris-imidazolium and benzimidazolium ionic liquids.

Novel tetrakis-imidazolium and benzimidazolium ILs containing tetra-ester groups with incorporated quadruple side chains were synthesized successfully as degradable surfactants of expected medical and industrial applications.