Synthesis And Construction Of Self-healing Hydrogel With Cross-linking Induced Thermal-response

In the introduction of the first chapter,the application and development direction of different kinds of hydrogels,and the design ideas of this topic are mainly introduced.Herein,In the second chapter,a series of P?DMA-stat-DAA?polymers were prepared by RAFT polymerization from monomer DMA?N,N-dimethylacrylamide?and DAA?diacetone acrylamide?.Then,a series of dihydrazide compounds were used as cross-linkers to prepare hydrogels with regulated cross-linking induced thermo-responsiveness?CIT?.The self-healing properties,gel-sol-gel transformation,and the temperature-sensitive properties of various hydrogels had been studied.Interestingly,although the copolymers did not show any thermo-responsivity,the hydrogels showed thermo-responsiveness with regulated cloud points,which varied with the composition of the copolymers and group ratios of the dihydrazide cross-linkers.Compared to some thermo-sensitive hydrogels prepared from thermo-sensitive polymers,the CIT property provided a new method to prepare thermo-responsive hydrogels from non-thermo-responsive polymers,and the catalysis-free self-healable hydrogels with thermo-responsiveness could have great potential applications in areas related to bioscience and biotechnology.In the third chapter,based on the experimental content of the second chapter,the TPE as a luminescent group was introduced to the middle of the copolymer to prepare fluorescent hydrogels with self-healing properties.The introduction of the hydrophobic group TPE regulates the hydrophilicity of the polymers,thereby obtaining thermo-responsive polymers.Not only the thermo-sensitivity and luminescence of polymer?TPE-[P?DMA-stat-DAA?]₂?,the luminescence,self-healing properties,gel-sol-gel transition and rheological properties of hydrogels were studied.In addition,by studying the vitro cytotoxicity and vitro drug release of hydrogels,luminescent hydrogels with good biocompatibility were obtained.It was found that by introducing the AIE characteristics into the self-healing hydrogels,temperature-regulated luminescence properties can be prepared.This kind of hydrogel will have potential applications in biological sciences and biotechnology,including biodiagnostic and drug delivery systems.In the fourth chapter,the TPE polymer was synthesized in the same manner and the TPE waas moved to the polymer end.The temperature sensitivity of polymers and hydrogels was also studied,and other properties such as thermo-responsiveness,luminescence,self-healing properties,and drug release in vitro of hydrogels were also studied.A temperature-regulated luminescent performance hydrogels were also obtained.