Application Of Photosensitive (2-Nitro-1,4-Phenylene) Dimethanethiol In Polymer Synthesis And Their Photo Degradation Mechanism

Stimuli-responsive polymers refer to the polymers whose physical or chemical properties change correspondingly under the stimulation of external environment.They are widely used in drug delivery,tissue repair,biosensors and other fields due to their high sensitivity and good biocompatibility.Currently,there are several kinds of stimuli responsive polymers such as pH responsive,temperature responsive and photo responsive polymers,etc.,among which photo responsive polymer has many dominant advantages in many areas due to spatial and temporal controllability properties,especially in drug delivery.Herein,we synthesized photosensitive monomers:(2-nitrophenyl)methanethiol and(2-nitro-1,4-phenylene)dimethanethiol,then a series of model small molecules and photo responsive polymers were made by thiol click reaction,which were demonstrated to be degradable under the UV irradiation of 365 nm,and we studied the degradation mechanism of model compounds.This thesis is divided into four parts:Part 1,Two photosensitive monomers(2-nitrophenyl)methanethiol and(2-nitro-1,4-phenylene)dimethanethiol were synthesized and the photo degradation mechanism of their corresponding model compounds which reacted with methyl acrylate were characterized in detail.Then the photo responsive polymer was prepared from dithiol and 1,6-Hexanediol diacrylate by thiol-ene click reaction and its structure and photo degradation property were characterized.Part 2,The model compound was made from dithiol and Propylene oxide and its structure and photo degradation property were characterized.Then the photo responsive polymer was prepared from dithiol monomer and 1,4-Butanediol diglycidyl ether by thiol-epoxide click reaction and its structure and photo degradation property were characterized.Part 3,The photo responsive polymer was prepared from dithiol and Hexamethylene dibromide and its structure and photo degradation property were characterized.Part 4,Two model compounds were made from two monomers which reacted with Hexanoyl chloride and their structure and photo degradation mechanism were characterized.Then the photo responsive polymer was made from dithiol and adipoyl chloride and its structure and photo degradation property were characterized.