Polyglyceryl Ester based surfactants – an attractive green alternative to the current non- ionic surfactants.

The consumer demand in personal care for “natural” non-ionic surfactants is growing. The current offerings are mainly based on petrol derived non-ionics and the alkyl polyglucoside based surfactants are one of the few exceptions. In this paper we will present results on relatively new and little known surfactants entirely based on natural renewable sources – polyglyceryl esters. The lack of enough data on their functionality in the literature and their full characterisation has delayed their penetration in a crowded cosmetics market and this presentation will try address this gap. The provided data will manifest the surfactants’ ability to reduce the surface/interfacial tension to very low values. Their mildness combined with an excellent foamability profile make them the surfactant of choice for formulations aimed at sensitive skin consumers

Structural Features of Reconstituted Wheat Wax Films

Cuticular waxes are essential for the well-being of all plants, from controlling the transport of water and nutrients across the plant surface to protecting them against external environmental attacks. Despite their significance, our current understanding regarding the structure and function of the wax film is limited. In this work, we have formed representative reconstituted wax film models of controlled thicknesses that facilitated an ex vivo study of plant cuticular wax film properties by neutron reflection (NR). Triticum aestivum L. (wheat) waxes were extracted from two different wheat straw samples, using two distinct extraction methods. Waxes extracted from harvested field-grown wheat straw using supercritical CO(2) are compared with waxes extracted from laboratory-grown wheat straw via wax dissolution by chloroform rinsing. Wax films were produced by spin-coating the two extracts onto silicon substrates. Atomic force microscopy and cryo-scanning electron microscopy imaging revealed that the two reconstituted wax film models are ultrathin and porous with characteristic nanoscale extrusions on the outer surface, mimicking the structure of epicuticular waxes found upon adaxial wheat leaf surfaces. On the basis of solid–liquid and solid–air NR and ellipsometric measurements, these wax films could be modelled into two representative layers, with the diffuse underlying layer fitted with thicknesses ranging from approximately 65 to 70 Å, whereas the surface extrusion region reached heights exceeding 200 Å. Moisture-controlled NR measurements indicated that water penetrated extensively into the wax films measured under saturated humidity and under water, causing them to hydrate and swell significantly. These studies have thus provided a useful structural basis that underlies the function of the epicuticular waxes in controlling the water transport of crops