Preparation Of Metal-metal Oxide Nanoparticles And Self-assembly Of PS-b-PAA/metal-metal Oxide Nanoparticles

In this thesis, we study the self-assemble of copolymers(polystyrene-b-polyacrylic acid) and nanoparticles. First we report the synthesis and characterization of anatase TiO2 nanosheets(NSs) with high surface area and of dumbbell-like Au-Fe3O4 NPs via thermal decomposition. Then 4-hydroxythiophenol(HTP) was utilized to modify the poly(styrene-b-acrylic acid)(PS-b-PAA) block copolymers(PS-b-PAA-g-HTP) by the esterification reaction between the carboxyl groups and hydroxyl groups. Moreover, the self-assembly behaviors of the PS-b-PAA-g-HTP and PS-b-PAA in dilute solution was also investigated. eventually, we study the co-selfassemble of PS-b-PAA and nanoparticles. Two main methods, including in-situ and ex-situ methodology, were applied to prepare the complex micelle.Iron pentacarbonyl in the diluted PS-b-PAA/1,4-diethylbenzene solution was directly used to in situdecompositeformation of a complex micelles. In dilute solution self-assemble of PS-b-PAA and dumbbell-like Au-Fe3O4 NPs prepare complex micelle by adding poor solvent.(1) we report the synthesis and characterization of anatase TiO2 nanosheets(NSs) with high surface area via thermally decomposition of titanium tetraisopropoxide(TTIP). During the synthesis procedures, only one kindof surfactant, oleylamine(OM), was used as the capping agent and no other solvents were added. The results indicate that the TiO2 NSs possess high surface area up to 396 m2/g. The concentration of capping agent is found to be a key factor to control the morphology and crystalline structure of the products. Moreover, adsorption and photodegradation experiments reveal that the prepared TiO2 NSs exhibit high adsorption capacity of model pollutants MB and high photocatalytic activity. We also synthesize and characterize the dumbbell-like Au-Fe3O4 NPs and quantum size spherical Au-FeFe2O4 NPs, which show the potential applications in drug delivery, photoelectric sensor and sunscreen cosmetic.(2) 4-hydroxythiophenol(HTP) modified poly(styrene-b-acrylic acid)(PS-b-PAA) block copolymers(PS-b-PAA-g-HTP) was synthesized using the esterification reaction between the carboxyl groups and hydroxyl groups. The esterification reaction is the partly modification of PAA block rather than a simple end-group modification. Lastly, self-assembly behavior of the PS-b-PAA-g-HTP and PS-b-PAA in dilute solution was investigated. In a dilute mixed solution of chloroform and dimethyl sulfoxide, the spherical micelles of PS-b-PAA and wormlike micelles of PS-b-PAA-g-HTP were obtained respectivelyby solvent evaporation method, while spherical micelle of PS-b-PAAand porously bowl-shaped structure of PS-b-PAA-g-HTPwere prepared via adding water to in a dilute solution of 1,4-dioxane.(3) The co-selfassemble of PS-b-PAA and nanoparticles was used to prepare the complex micelle. In PS-b-PAA/1,4-diethylbenzene dilute solution, the thermal decomposition of Iron pentacarbonyl in air or nitrogen was utilized to prepare the complex micelle. In the nitrogen atmosphere, iron was obtained by the thermal decomposition of iron pentacarbonyl. After cooling to room temperature, the displacement reaction of HAuCl4 by Fe happened in the above system, resulting the formation of the complex micelles. On the other hand, the assembled complexs of PS-b-PAA with dumbbell-like Au-Fe3O4 NPs or PS-b-PAA-g-HTP with dumbbell-like Au-Fe3O4 NPs were prepare by adding poor solvent in the dilute solution.