Construction Of Functional Polymers Based On Pillar[5]arene And Their Applications In Removal Of Micropollutants From Water

Since the first report of pillararenes in 2008,they attracted extensive attention of supramolecular chemists due to their unique symmetrical and rigid columnar structure and excellent host-guest recognition characteristics.Researchers have constructed many polymers based on pillararenes.In addition,various polymers based on pillararenes have been widely studied and applied in drug loading,sensing,catalysis,artificial light capture,self-healing materials,etc.Due to the inherent cavity structure and excellent host-guest recognition properties of pillararenes,as well as the outstanding performance of polymers based on previous generations of macrocyclic compounds in adsorption,theoretically,polymers based on pillararenes will also display excellent adsorption properties.Up to now,there has been less report on the adsorption of polymers based on pillararenes,especially polymer materials that adsorb pollutants from water.Therefore,the research on pillararene-based polymers in the field of adsorption is worth exploring.On one hand,the potential of pillararenes can be further explored,and the application of pillararenes can be extended.On the other hand,it can enrich the field of adsorption materials.This thesis mainly studies the construction of polymers based on pillar[5]arenes and their applications in the removal of pollutants from water.The main research contents and conclusions are described as follows:（1）An AB-type monomer based on a pillar[5]arene host and an imidazolium salt guest was successfully synthesized through a facile way.This monomer can self-assemble into linear supramolecular polymers in chloroform.Due to the metal coordination between imidazolium and silver ions,supramolecular polymer networks based on AB-type monomers and silver ions have been successfully constructed.In addition,the supramolecular polymer networks can be used to adsorb organic dyes from water and can be recycled.（2）An AB₂-type monomer based on a pillar[5]arene host and an azastilbene derivative guest was synthesized by a facile method.In chloroform,the AB₂-type monomer self-assembled to form a supramolecular hyperbranched polymer gel.After adding acid,the protonated monomer can also form another supramolecular hyperbranched polymer gel,and they can achieve reversible conversion by adjusting pH conditions.It is worth noting that the above two supramolecular hyperbranched polymer gels can effectively remove metal ions and organic dyes from water.（3）Through the amidation reaction between the amino group at the edge of graphite phase carbon nitride（g-C₃N₄）and the carboxyl group on carboxylatopillar[5]arenes（CP5）,the organic-inorganic hybrid material（CP5-g-C₃N₄）based on pillar[5]arenes and g-C₃N₄was prepared.The initial g-C₃N₄showed blocky structure composed of small nanosheets stacked closely.While CP5-g-C₃N₄displayed a smaller blocky structure composed of smaller nanosheets stacked,and the surface showed a looser structure than g-C₃N₄.In addition,their applications in removal of organic dyes from water were studied.The results showed that CP5-g-C₃N₄can rapidly and efficiently remove organic dyes from water,and the removal rate is significantly better than that of bulk g-C₃N₄which doesn’t by modified by pillararene.（4）The modified chitosan（CP5-CS）was obtained by crosslinking chitosan（CS）with CP5.In addition,CS shows a smooth surface with only a small amount of wrinkles,while the surface of CP5-CS is full of wrinkles and the roughness and specific surface area are significantly increased.Importantly,CP5-CS shows a stronger ability to remove organic dyes from water than CS,not only with higher total amount of dyes,but also with faster removal rate.