| Gel is a hot research material in recent years.It is a kind of three-dimensional network structure formed by chemical crosslinking or physical crosslinking,which can be swelled and dissolved in solvents.According to the different solvents,gels can be divided into hydrogels,organic gels and aerogels.Among them,interpenetrating network hydrogel(IPN)is particularly attractive.In this paper,a series of IPN hydrogels were synthesized by click reaction tandem photopolymerization.The properties of the hydrogel were characterized and their applications were explored in drug delivery.In addition,because the gel formed by supramolecular assembly often has the advantages of injectable and thixotropic,we have prepared two novel organic gels based on supramolecular assembly-eutectic gel and ionic liquid gel,and applied it to the flexible electrochromic field.The specific research contents are as follows:(1)Firstly,the soluble starch was modified with 3-maleimidopropionic acid(MI)to synthesize macromolecular dienophile,and hydroxypropyl methylcellulose was modified with succinic acid amide(SFA)to synthesize macromolecular diene.Then,the macromolecular dienophile,macromolecular diene,polymerizable β-cyclodextrin(CD-MAH),crosslinking agent,the monomer(acrylamide)and photoinitiator were dissolved in water.The mixed solution was heated at 50 ℃ for 3 h and the first network was formed by Diels-Alder reaction without catalyst,then the second network was formed by UV polymerization.Finally,5-fluorouracil(5-Fu)and isoniazid were used as model molecules to study the sustained release behavior of the drug-loaded hydrogels.(2)Firstly,the soluble starch was modified with azido acetic acid(AA)and MI to synthesize macromolecular dipoles and macromolecular dienophile,respectively.Then,the macromolecular dipole,macromolecular dienophile,CD-MAH,crosslinking agent,the monomer(N-isopropylacrylamide)and photoinitiator were dissolved in water.The mixed solution was heated at 50 ℃ for 3 h and the first network was formed by 1,3-dipolar cycloaddition reaction without catalyst,then the second network was formed by UV polymerization,thus obtaining the thermal sensitive IPN hydrogels.Finally,5-Fu and isoniazid were used as model molecules to study the sustained release behavior of the drugloaded hydrogels.(3)Firstly,the copolymer containing anhydride group was synthesized by free radical polymerization using acrylamide and maleic anhydride as monomers.Then it was dissolved in water with polyacrylamine hydrochloride,N-isopropylacrylamide,2-acrylamido-2-methylpropanesulfonic acid,crosslinking agent(polyethylene glycol dimethacrylate)and photoinitiator.The mixed solution was heated at 50 ℃ for 1 h and the first network was formed by click reaction based on anhydride and amino group,then the second network was formed by photopolymerization under UV lamp.A thermal and p H sensitive IPN hydrogel was prepared.Finally,isoniazid was used as a model molecule to study the sustained release behavior of drug-loaded hydrogels.(4)A series of supramolecular gelators GDL-n(n =6,10 and 12)with a simple structure of bisymmetrical glucosamides were synthesized.The gelators could form gels in seven ionic liquids(ILs)and four deep eutectic solvents(DESs).Gelation occurs due to hydrogen bond synergy between amide bonds and polyhydroxyl groups,as well as hydrophobic interactions between long alkyl chains.The gel was assembled into an ECD,and it was found that it had the characteristics of fast response time,low working voltage and good cycle stability,so it was an ideal material for preparing flexible electrochromic devices. |
