Synthesis And Gelation Properties Of N-amino Alkyl And Aryl Acetal Substituted Glucosamide Derivatives

A series of N-amino alkyl and aryl acetal substituted glucosamide derivatives Bn(n=0,2,4,6,8,12)with a free amino group at the terminal position of a long alkyl chain were designed and synthesized to study their structure-gelation relationship.Two-component gelators obtained by mixing Bn with aliphatic acids and the gel abilities,rheological properties and potential applications of two-component gels were studied.It was found that B4,B6 and B12 were potent gelators in certain organic solvents.B0 which derived from D-gluconic acetal with hydrazine did not exhibit gelation abilities in all the tested solvents.The rheological studies showed that these gels had weak thixotropy,and the storage modulus tended to increase with the decrease of the length of methylene chain.The storage modulus of B6/chlorobenzene gel was the highest,and the loss factor and flow point were the lowest.SEM showed that Bn(n=2,4,6,8,12)gels were formed three-dimensional network structures,in which the fibers' surface of B6 was smooth and the fiber diameter was the largest.IR indicated that with the increase of the length of methylene chain of Bn,there was no obvious change of hydrogen bonding interaction,but van der Waals force increased.The two-component gels consisted Bn(n=0,4,6,12)and a variety of aliphatic acids.It was found that the addition of aliphatic acids did not induce B0 to form gels and did not change that the gel abilities of B4 and B12.While the gel properties of the B6 were significantly changed.B6-A18 gels exhibited high-efficiency self-healing and phase selective properties,and found potential applications in the fields of flexible optical device fabrication and waste water treatment.The viscoelasticity and self-healing properties of gels can be successfully tuned by changing the length of alkyl chain of aliphatic acid component.Also,the powder of the two-component gelator could directly gel aromatic solvents from their mixtures with water at room temperature.SEM image showed that B6-A18 was self-assembled into well-defined1 D fiber bundles with an average diameters of about 1?m.IR and XRD showed that B6-A18 gel was formed by the synergistic effect of intermolecular hydrogen bonding,van der Waals,acid-base interactions and ?-? stacking.