Preparation And Characterisation Of Cyclodextrin Hydrogels Based On Diene Synthesis Reaction

Diene synthesis reaction (Diels-Alder) is a high selectivity reaction under mildreaction conditions.Cyclodextrin polymer not only form supramolecular structure inclusion but alsocan be modified by functional groups. Therefore, cyclodextrin hydrogels are preparedby diene synthesis reaction. In this paper, diene synthesis reaction was introduced intothe process of preparing hydrogels and through modified cyclodextrin or withcyclodextrin to the self-assembly in the water that successfully prepared three kinds ofpolymer dienes that are acrylic acid of2-furfurylamine diene, polyvinyl alcohol (PVA)of acetal diene, polyethylene glycol (PEG)2000of amide diene. Then they processdiene synthesis with crosslinking. At last, three kinds of hydrogels are prepared asfollows: maleic anhydride cyclodextrin hydrogels, PVA cyclodextrin hydrogels, andsupramolecular cyclodextrin hydrogels.In the process of cyclodextrin hydrogel containing maleic anhydride, first, thereaction is took place between maleic anhydride and furfuryl amines. Secondly, thepolymer diene is prepared by the polymerization reaction with different ratios ofN-isopropyl acrylamide polymerization. Crosslinking agent is prepared byhydroxyethyl β-cyclodextrin with AMI. At last, two kinds of hydrogels were preparedby two methods: The characteristics of hydrpgels were researched by FTIR, UV,NMR, GPC, and SEM. The results show that two methods can make hydrogels,hydrogels swelling consistent with the secondary kinetics and the hydrogels prepared byheterogeneous method can be used as injectable hydrogels.In the process of cyclodextrin hydrogel containing PVA, the diene was preparedby acetalization of PVA with furfural and crosslinking agent also used hydroxyethylβ-cyclodextrin-AMI. The hydrogels were prepared by diene synthesis reaction. Thecharacteristics of hydrogels were researched by FTIR. The results show that the hydrogelsswelling is also consistent with the secondary kinetics, drug release mechanism offour kinds of different acetal degree of hydrogels is different and the preparedhydrogels can be used as delivery carriers of water-insoluble drug.In the process of preparing supramolecular hydrogels, first, polyethylene glycol(PEG) was modified by succinic anhydride. Secondly, the reaction was carried outbetween modified product and furfuryl amine. Thirdly, supramolecular hydrogelswere prepared by α-CD with the reaction product of modified product and furfuryl amine in the water. Crosslinking agent was prepared by two processes. Firstly,polymerization is by hydroxyethyl methacrylate and N, N-dimethyl acrylamide.Secondly, crosslinking is prepared by the polymer with AMI reaction. At last, thehydrogels were also prepared by diene synthesis reaction. The characteristics ofhydrogels were researched by NMR, TG, XRD. Both of swelling kinetics and drugrelease behavior were researched, and the results show that the hydrogels can be usedas delivery carriers of water-soluble drug.