Synthesis And Gelation Properties Of Acetal-based Gluconamide Compounds

A series of novel D-gluconic acetal-based gelators with a flexible alkyl chain were synthesized to study their structure-activity relationship in iso-octanol.It was found that gelator G8 showed interesting multi-stimuli responsiveness and versatile applications.D-gluconic acetal-based gelators could gelate a variety of organic solvents and all the iso-octanol gels exhibited thixotropic property.The lengths of the alkyl chains had a profound effect on the thermodynamic and rheological properties of these compounds.The variation of the ratio of the storage modulus values of original gel torecovered gels(SM)and the ratio of the storage modulus to loss modulus(mechanical stability)showed a similar trend.SEM?IR and XRD studies suggested that the change of self-aggregation properties of the gelators with different alkyl chains due to changing of the driving force.The variation of SM and mechanical stability may closely related to van der waals interactions.Further studies revealed that G8 was a super gelator and exhibited interesting multi-stimuli responsiveness and versatile applications.For example,G8-based gels displayed chemical(base,anions)and physical(ultrasound,mechanical)stimuli and controllable phase transitions.In particular,anion responsiveness was found to follow the Hofmeister series in a non-aqueous system,which was rarely recorded.Applications in versatile fields were demonstrated for G8 such as being rheological and self-healing agents,waste water treatment,spilled oil recovery and flexible optical device manufacture.All gels of G8 that formed in a variety of organic solvents exhibited thixotropic property and showed diverse thixotropic properties that the degree of thixotropy and kinetics of recovery of viscoelasticity are varied.FT-IR,XRD and CAM studies showed that the change of morphology and rheological properties were attributed to the different driving force and molecular packing arrangements between gel and recovered gels among which the variation of SM may closely related to van der Waals interactions.In addition,the relevance of solubility parameter and the rheological properties of gels were discussed.We found that the dispersive force components in Teas parameter has positive correlation with the ratio of storage modulus and loss modulus,and the polar force component in Teas parameter has negative correlation with the recovery time of gels.