Solvent-Induced Polymorphic Nanoscale Transitions for 12-Hydroxyoctadecanoic Acid Molecular Gels

12-Hydroxyoctadecanoic acid (12HSA) molecular gels have been reported to form self-assembled fibrillar network (SAFiNs) in organic solvents. For the first time, different polymorphic forms for 12HSA molecular gels have been reported. 12HSA, in alkanes and thiols, have a hexagonal subcell spacing (similar to 4.1 angstrom) and are arranged in a multilamellar fashion with a distance greater than the bimolecular length of 12HSA (similar to 54 angstrom). This polymorphic form corresponded to SAFiN with CGC less than 1 wt %. 12HSA, in nitriles, aldehydes, and ketones, have a triclinic parallel subcell (similar to 4.6, 3.9, and 3.8 angstrom) and interdigitation of the lamellar structure (38-44 angstrom). This polymorphic form corresponds to a less effective sphereultic supramole cularcrystalline network, which immobilizes solvents at CGC greater than 1.5 wt %.