The unique nanostructure of shellac films
A new study aimed at exploring the nanostructure of shellac and gaining insights into the structure-property relations alongside the effect of its aging phenomena.
Shellac is a biocompatible resin of natural origin, comprising a mixture of polyesters and single esters, commonly used as a protective coating in the food and pharmaceutical industries. Remarkably, the physicochemical characteristics of shellac, in particular its excellent film forming, low vapor permeability, and good adhesion properties, are very untypical to low molecular weight materials.
Experiments revealed a unique bicontinuous nanostructure in shellac. Using manipulations of shellac’s composition and studies of shellac solutions in ethanol, the reseacrhers could identify the hydrophilic phase, the lipophilic phase, and the amphiphile residing on the interface between them.
Utilisation for novel applications
Although significant effort has been devoted to generating and stabilising bicontinuous molecular organisation in man-made systems, it was surprising to the researchers to discover that the conditions required for this unique morphology exist in native shellac. According to the scientists, understanding this exceptional morphology may open the way for further manipulation that will enable better control over shellac’s properties and its utilisation for novel applications, such as a coating material in drug or pesticide delivery systems.
The study has been published in Progress in Organic Coatings, Volume 157, August 2021.
