Stanimirova Rumyana D, Danov Krassimir D, Georgiev Mihail T, Petkov Jordan T
Department of Chemical & Pharmaceutical Engineering, Faculty of Chemistry & Pharmacy, Sofia University, 1164 Sofia, Bulgaria.
Department of Chemical & Pharmaceutical Engineering, Faculty of Chemistry & Pharmacy, Sofia University, 1164 Sofia, Bulgaria.
J Colloid Interface Sci. 2025 Jan;677(Pt A):250-263. doi: 10.1016/j.jcis.2024.07.219. Epub 2024 Jul 29.
Polyglycerol esters of fatty acids are generated via the esterification of a polydisperse mixture of polyglycerol with naturally derived fatty acids. The polymerization process of polyglycerol results in the production of various oligomers, ranging from di-, tri-, and higher-order forms, which contribute to the complexity of final products. The combination of complementary experimental techniques and adequate theoretical interpretations can reveal the wide variety of their physicochemical properties.
The colloid and interface properties of polyglyceryl mono-laurate, mono-stearate, mono-oleate, and a mixture of mono-caprylate and mono-caprate esters solutions were characterized by measurements of the electrolytic conductivity, static and dynamic surface tension, aggregate and micelle sizes and distributions, thin liquid film stability and stratification, and solubility in aqueous and in oil phases. The formation, stability, and bubble size distribution of foams generated from polyglycerol esters aqueous solutions were systematically investigated.
The low concentrations of double-tail molecules and fatty acids in polyglycerol esters affect considerably their micellar, aggregation, and vesicle formations in aqueous solutions. The theoretical data interpretation of polyglycerol esters isotherms and thin liquid films data provide information on the adsorption energies, excluded areas per molecule, interaction parameters of molecules at interfaces, surface electrostatic potential, and the size of micelles. Polyglyceryl mono-oleate exhibits spontaneous emulsification properties. Short chain length polyglycerol esters have excellent foaming ability but relatively low foam stability. The optimal weight fractions of the short-chain polyglyceryl esters and polyglyceryl mono-stearate mixtures with respect to good foaminess and foam stability upon Ostwald ripening are obtained. The reported physicochemical characterization of the water-soluble polyglycerol esters could be of interest to increase the range of their applicability in practice.
脂肪酸聚甘油酯是通过聚甘油的多分散混合物与天然衍生脂肪酸的酯化反应生成的。聚甘油的聚合过程会产生各种低聚物，从二聚体、三聚体到更高阶形式，这导致了最终产品的复杂性。互补的实验技术与适当的理论解释相结合，可以揭示它们多种多样的物理化学性质。
通过测量电导率、静态和动态表面张力、聚集体和胶束的大小及分布、薄液膜稳定性和分层情况以及在水相和油相中的溶解度，对聚甘油单月桂酸酯、单硬脂酸酯、单油酸酯以及单辛酸酯和单癸酸酯混合物溶液的胶体和界面性质进行了表征。系统研究了聚甘油酯水溶液产生的泡沫的形成、稳定性和气泡大小分布。
聚甘油酯中低浓度的双尾分子和脂肪酸对其在水溶液中的胶束形成、聚集和囊泡形成有相当大的影响。聚甘油酯等温线和薄液膜数据的理论数据解释提供了有关吸附能、每分子排除面积、界面处分子的相互作用参数、表面静电势以及胶束大小的信息。聚甘油单油酸酯具有自发乳化特性。短链长度的聚甘油酯具有优异的发泡能力，但泡沫稳定性相对较低。获得了短链聚甘油酯与聚甘油单硬脂酸酯混合物在奥氏熟化时具有良好发泡性和泡沫稳定性的最佳重量分数。所报道的水溶性聚甘油酯的物理化学表征可能有助于扩大其在实际应用中的范围。
