Design,Synthisis And Application Of Novel Photosensitive Polythioethers

Stimuli responsive polymers are the special polymers that can change according to the environment they are in.Usually, slight changes in the environment are sufficient to induce large changes in their structure,physical and chemical properties. Due to their high sensitivity and good biocompatibility, they have been used widely in the fields of intelligent optical materials, biomedicine, sensors etc. At present, stimuli responsive polymers can be divided into many types, such as: pH-sensitive,temperature-sensitive, photo-sensitive, redox sensitive enzyme sensitive etc. and they have used in different fields according to their different sensitive properties. Spatially and temporally controlled of light exposure represents many advantages in many fields, typically in drug delivery.Herein, we synthesized a group of new type photosensitive polymers,which can be degraded under ultraviolet irradiation, and studied its potential application in biomedicine. This thesis consists of three parts:Part 1, Two types of monomers, which are a photosensitive dithiol and some different acrylates. Then a variety of photo-sensitive polythioether materials by thiol-ene "click" reaction in solution, and the degradation property of some polymers were investigated under irradiation.Part 2, Three kinds of pH-sensitive acrylate monomers were synthesized, and were used to react with the dithiol monomer to synthesize the pH/UV dual responsive polymers. And the degradation properties of the polymer were investigated under acid and ultraviolet irradiation.Part 3, The application of the polythioether materials in the field of biological medicine were investigated. Firstly, we were successfully formulate PVA/Polythioether particles and encapsulate Nile red within,and the drug release kinetics were investigated under the different illumination time; secondly, an amphiphilic polythioether which was synthesized by poly(ethylene glycol) diacrylate and the dithiol, it was used to encapsulate Nile red, and the drug release kinetics was also investigated under the different illumination time...