Vesiculation and Stability : Oligomer of Conjugated Linoleate Acids Prepared by High Internal Phase Self-emulsion Polymerization

High internal phase O/W emulsion of conjugated linoleic acids (CLA) was prepared by selfemulsifying technology, and oligomer of CLA (oligo-CLA) was obtained by thermal self-emulsion polymerization(SEP) of the above emulsion. Furthermore, fatty acid vesicles (FAV) self-assemble by the oligo-CLA showing 10-30 nm diameter at pH =8. 6-13 that was revealed by both transmission electron microscopy and dynamic light scattering, which has theoretical significance for FAV stable at a broader pH range. The experimental results show that free-surfactant emulsion polymerization was completed in the high internal phase emulsion of 75. 3% (mass fraction) CLA according to the unique self-emulsification/thermal oligomerization strategy, achieving 33% total self-crosslinking degree and the target oligo-CLA with an average polymerization degree of 6, which is instructive for scaling up oligo-CLA and FAV preparation. The oligo-CLA has better low temperature solubility in comparison with CLA itself, and the FAV self-assembling by it has stronger resistance to acidic and calcium conditions and shows calcium responsive size-tunable features. Moreover, the hybrid vesicles of oligo-CLA with a small amount of Span 40 or AEO, additives show even broader pH windows for vesiculation. Therefore the FAV self-assembling by oligo-CLA should have a wider application prospect in drug delivery systems, daily chemical products, and household detergents and personal care products.