| Supramolecular chemistry is concerned with the formation of ordered assemblies between molecules through intermolecular interactions（coordination bonds,hydrogen bonds,electrostatic interactions,π-πstacking,hydrophilic/hydrophobic and van der Waals forces）.Among the research objects of supramolecular chemistry,star-shaped supramolecular complexes show unique properties in solution self-assemble and hydrodynamics properties because of their unique structure.On the other hand,due to the special structure and properties of polyoxometalate,a variety of materials can be obtained by combining the polyoxometalate with some organic and inorganic molecules,which not only have the specific properties of polyoxometalate,but also produce new functions that polyoxometalate do not have,which can be applied in more fields.Therefore,the star-shaped supramolecular complexes,which are self-assembled by poly acid clusters as the core,are worth exploring as a kind of organic-inorganic hybrid materials with hierarchical nanostructures and intriguing properties.Based on the above background,this paper mainly does the following two work:In the first part,we synthesized two kinds of cationic surfactants and electrostatically self-assembled with negatively charged polyoxometalate(Mo132,W12).Four kinds of star-shaped supramolecular complexes were obtained and characterized in detail.SAXS/WAXS characterization showed that the four star-shaped supramolecular complexes had layered ordered structure.The four kinds of supramolecular complexes were added into the base oil to determine their lubricating properties.It was found that the supramolecular complexes formed by Mo132 showed better lubricating effect than those formed with W12.The supramolecular complex formed by Mo132 can maintain good lubricating effect for a long time under high load,which shows the good anti friction effect of additive added to base oil.The introduction of polyoxometalate clusters into lubricating system was discussed.In the second part,we introduce pyrimidine into quaternary ammonium salt to obtain a quaternary ammonium salt which can form tetra hydrogen bond.Furthermore,two star-shaped supramolecular complexes were formed by electrostatic self-assembly and polyoxometalate. |
