Organogel Formation Rationalized by Hansen Solubility Parameters: Shift of the Gelation Sphere with the Gelator...

Area of Science:

• Supramolecular Chemistry
• Materials Science

Background:

• Low molecular weight gelators (LMWGs) are crucial in developing novel materials.
• Understanding structure-property relationships in LMWGs is key for rational design.

Purpose of the Study:

• To investigate the impact of molecular structure, specifically alkyl chain length, on the gelation ability of thiazole-based gelators.
• To correlate gelation behavior with solubility parameters and molecular packing.

Main Methods:

• Extensive solubility tests using Hansen solubility parameter formalism.
• X-ray diffraction and molecular modeling to analyze molecular packing and fiber formation.
• Systematic variation of alkyl chain length in thiazole-based gelators.

Main Results:

• Increasing alkyl chain length in thiazole-based gelators expands the gelation sphere radius.
• A shift in the gelation sphere center towards lower polar (δP) and hydrogen bonding (δH) components was observed with longer alkyl chains.
• Consistent molecular packing across the studied gelators was confirmed.

Conclusions:

• Alkyl chain length is a critical determinant of gelation ability in these thiazole-based systems.
• The observed shifts in solubility parameters are attributed to reduced surface polarity with increased alkyl chain length.
• This study provides a rational framework for designing LMWGs with tailored gelation properties.