Supramolecular Functional Materials Constructed By Host-Guest Interactions And 3D Skeleton Of Pillar[5] Arene

As an important research field of supramolecular chemistry,the host-guest chemistry based-on macrocyclic host is always a hot topic among supramolecular chemists.In 2008,Ogoshi and Nakamoto synthesized and reported a symmetric pillar-like macrocyclic supramolecular host,which was named Pillararene.Since then,Pillararenes have been widely used in various fields due to their unique symmetry and rigid structures,simple functionalization methods,and excellent host-guest complexation properties.This greatly enriched the content of supramolecular chemistry and promoted the rapid development of supermolecular chemistry and even the entire chemistry world.Pillararenes are therefore also known as the fifth-generation macrocyclic host molecules after crown ethers,cyclodextrins,calixarenes and cucurbiturils.Then,in the research work of this dissertation,we focused on the construction of supramolecular polymer materials and supramolecular amphiphilic assembly materials constructed by pillar[5]arene-based host-guest recognition,and the three-dimensional network polymer based on the three-dimensional skeleton structure of pillar[5]arene for organic micropollutants treatment,which mainly includes the following parts:In the first part of the research work,we designed and synthesized a water-soluble pillar[5]arene monomer,and linear supramolecular polymers were efficiently constructed driven by pillar[5]arene-based host-guest interactions in water.The formation of the supramolecular polymer was highly dependent on the monomer concentration.Moreover,a rod-like fiber can be drawn from a high-concentration solution of the monomer,which provided a direct evidence for the formation of the linear supramolecular polymer.Furthermore,glue-sol phase transitions of the supramolecular polymers can be achieved by reversible heating and cooling.Considering the easy availability and good water-soluble properties of the monomer,the present work provided a new and simple method for fabrication of water-soluble supramolecular polymeric materials.In the secend part of the research work,a fluorescent supramolecular polymer was successfully constrcted by pillararene-based host-guest recognition and metal ion coordination.The reversible phase transitions of the fluorescent supramolecular polymer can be realized by heating and cooling,and the fluorescent supramolecular polymer showed base-stimulus responsiveness.Furthermore,the fluorescent emissions of the supramolecular polymer can be controlled by concentrations of the monomers.Moreover,the fluorescent supramolecular polymer based thin film can be prepared to conveniently detect OH-anions as a test kit.This new type of pillar[5]arene-based fluorescent supramolecular polymer may be of importance for the development of novel fluorescent materials and molecular devices in the future.In the third part of the research work,novel near infrared aggregation-induced emission active nanoparticles were fabricated by using the water-soluble pillar[5]arene-based host-guest complex as a building block.In contrast to the nanoribbons self-assembled from the guest molecule,the supramolecular amphiphile of the pillar[5]arene-based host-guest complex self-assembled into organic nanoparticles.The nanoribbons of the guest molecules show relatively weak fluorescent emission,while the nanoparticles show strong near infrared fluorescent emission at the same low concentrations due to the host-guest complexation enhanced aggregation.Furthermore,these nanoparticles can be utilized as an imaging agent for living cells because of their near infrared fluorescent emission property.This is the first time that near infrared aggregation induce emission active nanoparticles were constructed by pillar[5]arene-based host-guest interactions and further used for living cell imaging.Therefore,we reported a new method for the preparation of near infrared emissive nanoparticles based on pillar[5]arene host-guest chemistry.In the last part of the research work,a three-dimensional network polymer for the removal of organic micropollutants from water with high adsorption efficiency has been successfully prepared by crosslinking a carboxyl-derived pillar[5]arene with p-phenylenediamine.Specifically,the polymer is a superior adsorbent for fluorescein sodium and methyl orange in water with low synthetic costs,fast uptake kinetics and high removal capacity.In addition,by using a mild washing procedure,the polymer can be regenerated at least ten times with almostly no performance loss.These excellent properties of the polymer demonstrate that this polymer can be used for the removal of a wide range of micropollutants during water and waste-water treatment.