| Fibrous hydrous zirconia, spinnable hydrous zirconia chelated by acetylacctone and modifiedhydrous zirconia were synthesized from zirconium oxychlorid(ZrOCl2·8H2O) and then applied toprepare ZrO2/PVA electrospinning hybrid fibers, ZrO2/PVA continuous hybrid fiber and ZrO2/PVPhybrid microsphere respectively. The chemical structure, properties, microstructure and formationmechanism of the corresponding materials were investigated. The results will break a new path forapplication of ZrO2 in polymer field and provide foundmental theory to preparation and applicationof ZrO2/Polymer hybrid materials.The main work as follows:1. Amorphous hydrous zirconia was prepared by hydrolyzed and condensation of ZrOCl2·8H2Owith H2O2 as hydrolysis promoter in ethanol. The chemical structure and thermal stability of thehydrous zirconia were studied by FT-IR, TG and XRD, and the microcosmic structure and theformation process were clarified by light microscope and SEM. The results show that the hydrouszirconia has three different hydroxyl groups and the molecular formula is Zr(μ-OH)2(OH)2·2H2O.The hydrous zirconia is amorphous below 80℃, which changed gradually from metastabletetragonal phase to monoclinic phase as heat treatment temperature rise from 400 to 800℃. Thehydrous zirconia forms a short fiber cluster composed of many fine short fibers via the hydrogenbonds.2. A series of hybrid spin solutions of ZrO2/PVA with different zirconia contents were preparedby blending hydrous zirconia prepared at low pH value and 10 wt% PVA solution, and thenelectrospun fibers were obtained by electrospinning. The morphology, chemical structure, thermalstability and crystallization behavior of the fibers were analyzed by SEM,IR,TG,XRD, thestability and water absorption of the fibers were also studied. The results show that thehybrid is formed by the interaction of hydroxyl groups between PVA and hydrous zirconia.The thermal decomposition temperature of PVA rises from 200 to 250C after hybridizedwith ZrO2. The mean diameters of the fibers range from 100 to 400nm. The diameter of the fibersincreases firstly and then decreases with the increasing of zirconia content, while the beadsof the fibers increase. The higher the zirconia content, the more amorphous of the hybridfibers. Compare with PVA fibers, the stability and hydrophobicity of the ZrO2/PVA hybridelectrospun fibers arc both improved under different pH values.3. Continuous ZrO2 precursor fibers were prepared by sol-gel method with ZrOCl2·8H2O as rawmaterial, and then continuous ZrO2 fibers were obtained after the preoursors were sintered at 800℃.The chemistry structure, microstmcture and crystal form of the fibers were studied by FT-IR, TGA,SEM and XRD. The preparation process and influencing factors for the spinnability of zirconium solwere discussed. The results show that the zirconium sol has good spinnability when n(zirconium oxychlorid): n(dioxogcn)= 1:3, reaction time is 6h and aging temperature is 15℃. The ZrO2precursor fibers are made from hydrous zirconia chelated by acetylacetone. The sintercd fibers arecomposed of metastable tetragonal phase and sized about 15μm in diameter. Moreover, there aremany pores inside the fibers, but no cracks.4. ZrO2/PVP hybrid fibers were prepared by blending the spinnable zirconium sol and 10 wt%PVP solution. The chemistry structure, microstructure of the hybrid fibers and the influence of thehybrid degree on ZrO2 fibers sintered were studied by SEM, FT-IR, TGA and XRD.The resultsshow that the length of the ZrO2/PVP hybrid fibers, in the diameter of 10-25pro, can be more thantens meters. The hybrid between PVP and zirconium sol is formed by coordinate linkage. The hybridfibers retain the shape of fiber after sintered, but the diameter of the hybrid fibers get thin aftersintered. As the ZrO2 content in the hybrid turn low, the ZrO2 fibers become thin or oven craze. Thelower the ZrO2 content in the hybrid fibers, the smaller the crystal grains of ZrO2. The crystal grainsof ZrO2 increase with the increasing of sinter temperature for the constant ZrO2 content in the hybridfibers.5. PVP microspheres were preparaed by dispersion polymerization with NVP as initialmonomer, PVP-co-PVAc as dispersant and AIBN as initiator in ethyl acetate. The influences ofmonomer concentration, dispersant concentration and initiator concentration on the size of PVPmicrospheres, monomer conversion rate and the molecular weight were all investigated. Thestructure and properties of PVP microspheres were analyzed. The results show that the meandiameter of PVP microspheres is about 3～4μm. The size and the molecular weight of the PVPrnicrospheres increase, and the monomer conversion rate also increases with the increasing of NVPconcentration. The size of microspheres decreases and the molecular weight of the PVP and themonomer conversion rate increase with the increasing of PVP-co-PVAc concentration. The size ofmicrospheres and the monomer conversion increase, and the molecular weight of the PVP alsoincrease with the increasing of AIBN concentration. The PVP prepared by dispersion polymerizationhave crystalline structure and the molecular weight of PVP is lower compared with solutionpolymerization,.Based on the PVP dispersion polymerization, monodisperse ZrO2/PVP hybrid microspheres, inthe mean diameter of 2μm, were prepared with the hydrous zirconia molidfied by butanol as coreand PVP as shell through adjusting the dispcrsant concentration.
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