Role of ethyl cellulose polymer network on synergistic enhancement of glycerol monostearate and ethyl cellulose binary oleogels

Artikel i vetenskaplig tidskrift, 2026

Although ethyl cellulose (EC) and glycerol monostearate (GMS) have been shown to exhibit synergistic behavior over a range of concentrations, the specific role of EC in governing the cooperative behavior remains poorly understood. Accordingly, this study examines the role of EC in EC–GMS synergism by systematically varying EC molecular weight (low- and high-molecular-weight EC; EC10 and EC45, respectively) and EC concentration (0–10%), spanning regimes below, at, and above the critical gelation concentration (CGC) of EC. The magnitude of synergism is strongly dependent on EC network formation. At and above the CGC (i.e., 6 and 10% EC45, respectively), where EC forms a self-supporting, entangled polymer network, a pronounced enhancement of gel strength was observed. In contrast, below the CGC (i.e., 2% EC45 and 2–10% EC10), where EC cannot form a self-supporting network, synergistic enhancement was substantially weaker. Microstructural analysis revealed that the presence of EC altered the spherulitic morphology of GMS, producing smaller spherulites with increased nucleation density as EC concentration increased, suggesting enhanced EC–GMS interactions. EC also caused moderate reductions in the crystallization temperatures of the α and sub-α polymorphs of GMS (1–3 °C and 3–6 °C, respectively), with larger shifts observed at higher EC concentrations. EC also caused a depression in the onset temperature of crystallization, but crystallization rate was more rapid. Thermo-rheological measurements confirmed significantly higher storage modulus (G′) values for all EC–GMS oleogels, with formulations containing a self-supporting EC network exhibiting a stronger synergistic effect than those without network formation at equivalent concentrations. Improved thixotropic recovery was observed only when EC was present at or above its CGC. Overall, these findings highlight the central role of polymer network formation in governing EC–GMS synergism and provide new opportunities for designing cost-efficient oleogel-based fat mimetics through targeted control of EC molecular weight and concentration in multi-component oleogels.