Preparation Of Poly(ionic Liquid)s-based Nanogels And Their Host-guest Interaction

Supramolecular chemistry was studied on the assembled entities of higher complexity which resulted from the association of two or more molecules held together through non-convalent bonds?secondary bonds?.Host-guest interaction is a core content of supramolecular chemistry,as well as one of the main driving forces of self-assembly.As the respective second generation and forth generation of host molecules,cyclodextrin and cucurbituril have attracted tremendous attention in scientists due to their special structure and properties.In aqueous solution,cyclodextrin and cucurbituril can complex selectively with organic or inorganic molecules to form host-guest complexes via different non-convalent interaction.Because inclusion complex between host and guest is related with their matching degree,configuration and valence state of guest mo lecules,the association and dissociation of inclusion complex can be controlled by chemical induction,photo-irradiation,electrochemistry and so on.These host-guest complex systems have significant potential on designing and preparing stimuli-responsive functional materials and supramolecular nano-devices.Ionic liquid?IL?is a class of organic liquid salt around room temperature entirely composed of organic cation and inorganic or organic anion.It is regarded as green solvent and excellent electrolyte in green chemistry due to some remarkable properties,such as thermal stability,low volatility,non-flammability,high ionic conductivity,wide electrochemistry window,etc.In previous studies,our group demonstrated one-step synthesis strategy to prepare poly?ionic liquid?s?PILs?-based nanogel via crosslinking copolymerization of phosphonium salt-based ionic liquid and crosslinker in selective solvents without any stabilizer.Based on the previous studies,we herein prepared functional PILs-based nanogels through introducing azobenzene-containing ionic liquid monomer or naphthalene-based compound to copolymerize with phosphonium salt-based ionic liquid and crosslinker in selective solvent.The association and dissociation of PILs-based nanogels with host molecules?-cyclodextrin or cucurbit[8]uril were also investigated in order to apply nanoparticles to supramolecular chemistry.This thesis mainly contains three parts as following:1.The different ionic liquid monomers and functional compounds were synthesized,including1-vinyl-3-[6-?4-phenyl-azophenoxy?hexyl]imidazolium bromide?[VAzo HIm]Br?,4-?naphthalen-2-yloxy?butyl methacrylate?NpBMAc?,4-vinylbenzyl-triphenylphosphorous chloride?VBP-Ph?,4-vinylbenzyl-tributylphosp-horous chloride?VBP-Bu?,?-cyclodextrin dimer,cucurbit[8]uril,viologen dimer,and characterized using ¹H NMR,¹³C NMR,MS and DSC measurements.2.The light-responsive PILs-based nanogels were prepared via one-step strategy and the light-controlled association and dissociation between nanogel and?-cyclodextrin dimer were also investigated.The stable nanogels were prepared via crosslinking copolymerization of azobenzene-containing ionic liquid,phosphonium salt-based ionic liquid and crosslinker in selective solvent and characterized by UV-vis spectra,FT-IR,XPS,TG,DLS and SEM measurements.The results demonstrated the as-prepared nanogels show light-responsive and their sizes could be facilely tuned by alternating the wavelength of light or the feed ratio of IL monomer to crosslinker.Furthermore,the association and dissociation between nanogels and?-cyclodextrin dimer were reversibly controlled by alternative UV-vis irradiation due to azobenzene moiety and testified using UV-vis,DLS,SEM and 2D NOESY measurements.3.The functional PILs-based nanogels containing naphthalene were prepared via one-step strategy and the association and dissociation between nanogel and cucurbit[8]uril driven by host-stabilized charge-transfer?HSCT?interaction were also investigated.The stable nanogels were prepared via crosslinking copolymerization of naphthalene-based compound,phosphonium salt-based ionic liquid and crosslinker in selective solvent and characterized by UV-vis spectra,FT-IR,TG,DLS and SEM measurements.The results indicated the sizes of as-prepared nanogels could be facilely tuned through the feed ratio of naphthalene-based compound to crosslinker.In addition,the ternary association system between nanogels,viologen dimer and cucurbit[8]uril driven by HSCT interaction was formed and testified via UV-vis,¹H NMR,DLS and SEM measurements.However,with the addition of amantadine,the ternary system dissociated.