"Click Synthesis" And Properties Of Novel Cyclodextrins Derivatives And Polymers

Because of numerous peripheral hydroxyl in cyclodextrin, it could be modified to build new types of cyclodextrin derivatives by introducing special structures or functional groups. It is becoming a research hot spot in supramolecular field currently. However, the modification, the separation and purification of product is still a difficult problem. Click reaction catalyzed by copper ion has many advantages, such as the normal conditions, high yield, less by-product, simple separation, and so on. This method has become commonly one on synthesizing cyclodextrin derivatives.There is a activated hydroxyl in cholesterol which can be modified by various methods. Its derivatives have stable structure, properties and liquid crystal phase in some cases. These liquid crystal phases have wider temperature ranges of phase transition. And these liquid crystal has good thermal stability and higher thermal sensitivity. On the other hand, cyclodextrin polymers not only can keep the inclusion of cyclodextrin, but also be able to show its unique effect of polymer, for example, neighboring group effect, synergies and strong mechanical properties and so on. Thus, in this thesis, by using cyclodextrin as starting materials, we design and synthesis of a series of cyclodextrin derivatives and cyclodextrin polymers through click reaction. Also, their properties were studied. The main contents are as follows:The first chapter:Design and synthesis of two new type of cyclodextrin-cholesterol derivatives with cholesterol unit 5a and 5b. Their liquid crystal properties were studied by DSC, XRD and POM. Results showed that compound 5a has liquid crystalline behaviours, but compound 5b exhibits no liquid crystalline performance.The second chapter:Design and synthesis of three novel cyclodextrin derivatives containing amide group 8a,8b and 8c. All of them showed strong abilities of dye molecular recognition abilities based on the synergistic interaction of the amide group, nitrogen zole ring and hydroxyl of cyclodextrin.The third chapter:Design and synthesis of new type of cyclodextrin-thiacalix[4]arene dimer 12 and cyclodextrin-thiacalix[4]arene polymer 13. The XRD analysis indicated that the disappearance of some peakes and the reduction of the strength of peaks. The polymer 13 has a good inclusion capability for dyes.The fourth chapter: Design and synthesis of new type of cyclodextrin-chitosan polymer 14. SEM showed that this polymer presents loose foamy morphology. The studies on binding properties showed that it has a good inclusion adsorption capability for tested dyes.