Study Of Microstructured Hydrogels With Anti-biofouling Properties

Hydrogels are a class of biocompatible and hydrophilic crosslinked polymeric materials.In recent years,they have been widely used in many fields such as biomedicine,agriculture,water treatment,food industry,etc.In this thesis,a series of porous hydrogel materials and electrospun fiber-hydrogel composite materials which combined the advantages of both hydrogel materials and porous polymers were designed and prepared,and their properties were systematically investigated and studied.Applications of these materials,such as tissue engineering scaffolds,antifouling coatings and water treatment membranes,were further explored.Main contents of this thesis are as follows:Hydrogels with porous microstructure could promote the migration and proliferation of cells,and regulate the behavior of immune cells.In this work,porous poly(2-hydroxyethyl methacrylate)(PHEMA)hydrogels were successfully prepared using poly(?-caprolactone)(PCL)electrospun fibers as template.Abundant fibrous microchannels were formed in the hydrogel and their sizes could be controlled.The in vivo experiment results demonstrated that the porous structure rendered hydrogels with the performance which could effectively reduce the foreign-body reaction(FBR)of the host.Further,silver nanoparticles(AgNPs)loaded PHEMA hydrogel composite materials with uniform porous structure were successfully prepared by using poly(methyl methacrylate)(PMMA)polymer microspheres as templates.This hydrogel with pore size of 40?m was non-toxicity to cells.The antibacterial results of materials showed their antibacterial efficiency to E.coli and S.aureus all achieved 100%,indicating their good antibacterial properties.Moreover,they could efficiently reduce the FBR,completely prevent the formation of collagen capsule,while kill the bacteria and resist the implant-associated infection.The amalgamation of electrospun fibers and hydrogels can create composite materials combining their advantages.Inspired by the structure of interpenetrating polymer network(IPN),polystyrene(PS)electrospun fibers were used as supports for manufacturing electrospun fibers-zwitterionic hydrogel composite materials with fiber-reinforced microstructures.The composite materials combined the advantages of hydrophobic electrospun fibers and zwitterionic hydrogels,possessed excellent mechanical properties and machinability,and could effectively resist the contamination of proteins,cells,or even blood on their surfaces.Additionally,it displayed good blood compatibility and could effectively prevent the blood coagulation.Based on the preparation method of the composite material,an electrospun fiber-zwitterionic hydrogel composite membrane with porous microstructures was prepared.In comparation with 0.22?m PES membranes,the composite membranes displayed excellent antifouling properties.When the PU solution was 20%,the electrospun voltage was 17.5 kV,and the distance was 20 cm,the composite membrane displayed the optimal filtration performance,its bacterial rejection rate of E.coli and S.aureus all achieved 99.9%,and the water flux of membrane was 1349.20±85.05 L/(m~2·h)and1344.78±108.40 L/(m~2·h),respectively.The composite membrane displayed a higher flux recovery rate(~97%)compared to the 0.22?m PES membrane,indicated their antifouling properties in microfiltration process.Meanwhile,it could effectively and efficiently remove the Navicula Prava and Navicula Rows from water,of which water flux was 701.44 L/(m~2·h)and 1291.38 L/(m~2·h),respectively.Moreover,the composite membranes displayed a good reusability,the filter performance was highly maintained even after 100 filtration operations.This work developed four types of materials with different microstructures,which would offer new approaches for novel hydrogels and hold promises for various biomedical and water treatment applications.