Cellulose-Based Oleogels via One-Step Cross-Linking for Lubrication

Area of Science:

• Materials Science
• Tribology
• Polymer Chemistry

Background:

• Cellulose-based oleogels offer potential for sustainable lubrication.
• Incompatibility between cellulose and oils hinders oleogel formation.
• Controlling oleogel properties for specific applications remains a challenge.

Purpose of the Study:

• To develop novel, stable cellulose-based oleogels with tunable rheological properties.
• To investigate the effect of cross-linking density on oleogel performance.
• To explore their potential as bio-based lubricating materials.

Main Methods:

• Cross-linking reactions involving epoxidized soybean oil (ESO), microcrystalline cellulose (MCC), and isocyanate.
• Rheological characterization to assess shear-thinning, thixotropy, and plateau modulus (GN0).
• Thermal stability tests (T5%) and oxidation induction time (OIT) measurements.
• Tribological tests, including friction coefficient and four-ball extreme-pressure load-carrying capacity.

Main Results:

• Successfully developed stable cellulose-based oleogels with tunable properties.
• Achieved excellent thermal stability (T5% ~300 °C) and significantly enhanced oxidation resistance (OIT increased from 5 to 79 min).
• Oleogels exhibited shear-thinning and thixotropic behavior, with properties correlating to cross-linking density.

Conclusions:

• The cross-linking strategy effectively overcomes MCC-ESO incompatibility.
• Tunable cross-linking allows precise control over rheological behavior and structural recovery.
• These bio-based oleogels show promise for high-performance, customizable lubrication applications.