Self-assembly And Application Of Conjugated Compounds Based On Hydrogen Bonding And π-π Interaction

Molecular self-assembly through non-covalent bond interactions or covalent bond interactions is an important way to achieve material functionality,and has a wide range of applications for materials science,life science,information science,etc.Therefore,it is of great theoretical and practical significance to construct a functional self-assembly system and study the self-assembly driven process.In this paper,hydrogen bonds andπ-πinteractions were used to induce self-assembly of conjugated derivatives such as pyrene and tetraphenylethylene.Effects of hydrogen bond types,hydrogen bond strength,number of hydrogen bonds,self-assembly conditions,and other factors on the assembly morphology and structure were studied and explored the self-assembly mechanism and application.The main research contents are as follows:（1）Self-assembly and mechanism of pyrene derivatives based on hydrogen bond andπ-πinteraction.Construct a self-assembling system with 1,3,6,8-tetra（p-benzoic acid）pyrene（H₄TBAPy）,urea,melamine and amino-terminated hyperbranched polymer as the main materials.Self-assembly process was regulated by regulating the number of amino groups and the interaction with carboxyl groups.Polarized light microscope and scanning electron microscope were used to observe the morphology of the assembly H₄TBAPy-Urea,H₄TBAPy-MA and H₄TBAPy-HP,which were arched like long fiber,three-dimensional flower shape and banana shape.FT-IR,XRD,XPS,DSC,and other characterization technologies were used to study the factors affecting assembly appearance and the assembly mechanism.It was found that theπ-πinteraction of H₄TBAPy planar aromatic pyrene nucleus,the electrostatic interaction and hydrogen bonding interaction between the carboxyl group of H₄TBAPy and the amino group of urea,melamine and amino hyperbranched polymers induce self-assembly respectively.（2）Self-assembly and application of tetraphenylethylene derivatives based on hydrogen bonding andπ-πinteraction.The self-assembly of H₄tcbpe-MA was constructed with 1,1,2,2-tetrakis（4-（4-carboxy-phenyl）phenyl）ethylene（H₄tcbpe）and melamine as units.The molar ratio of H₄tcbpe and melamine could regulate the strength of the assembly driving force and then influences the particle stacking mode in the process of molecular assembly.The changes of self-assembled morphology were studied by polarizing microscope and scanning electron microscope.Experimental results show that nanofibers,tree-like,cuboidal microstructures,and micro-belts were generated with the ratio of H4tcbpe-MA at 1:0,1:1.5,1:3.0 and 1:6.0,respectively.Increasing the content of MA will lead to an increase in hydrogen bonding interactions,thereby weakening the intermolecularπ-πinteraction.Studies have shown that inter-ion interaction,hydrogen bonding andπ-πinteraction synergistically drive the assembly of H4tcbpe-MA.Self-assemblies shown different fluorescent color responses with changes in melamine concentration and relative humidity,giving assemblies potential applications in humidity monitoring.（3）COF materials were fabricated and supercapacitors were constructed based on self-assembly induced by hydrogen bondπ-πinteraction.Hydroxyl-terminated hyperbranched polymer（OHP）,2,6-diaminoanthraquinone and 1,3,5-trialdehyde resorcinol were used as raw materials to prepare COF@OHP complex.It was impregnated on the microporous carbon nanotube film（CNTF）to prepare a composite membrane（CHCM）and then further build a supercapacitor.The COF@OHP complex prevented the aggregation and collapse of COF and CNTF through the limiting effect of CNTF,increased theπ-πinteraction between COF and CNTF,and increased the electron conduction rate between COF and CNTF.Therefore,the CHCM electrode exhibited a mass capacitance of 249F g^-1 in phosphoric acid（H₃PO₄）electrolyte solution,and has a high tensile strength of 180 MPa and an elongation at break of 10%,making it in the practical application of flexible stretchable supercapacitors.