Synthesis And Application Of Micro/Nano La₂O₃

This thesis describes the synthesis of micro/nano La₂O₃ and its precursors by hydrothermal method and microemulsion-assisted solvothermal method.The structures,morphologies and sizes of product particles were analyzed and characterized by X-ray diffraction?XRD?,scanning electron microscopy?SEM?,thermogravimetic analysis?TG?and infrared spectra?FTIR?.Subsequently,the synthesized La₂O₃ was modified with stearic acid and characterized.Finally,the modified product was used in polyester dyeing.The best dyeing conditions were discussed based on the adjusting the amount of dyes,acetic acid,dispersing agent,methyl salicylate,as well as the reaction time,the reaction temperature and other facters by using the orthogonal experiment method.The specific contents can be summarized as follows:?1?The lanthanum oxide and its precuisor were synthesized by hydrothermal method with cetyltrimethyl ammonium bromide?CTAB?as surfactant,lanthanum nitrate and ammonium carbonate as raw materials.The effects of concentration of reactants,reaction temperature and reaction time on the morphologies and sizes of lanthanum oxide were investigated.The results showed that the synthesized lanthanum oxid particles are spherical.The size of the product decrease,with the increasing of the concentration of reactants and reaction temperature.The size of the product increase,with the expanding of reaction time.?2?The lanthanum oxide and its precuisor were prepared in W/O reverse microemulsion composed of n-octane,n-butanol,cetyltrimethyl ammonium bromide?CTAB?,lanthanum nitrate solution and ammonium carbonate solution by microemulsion-assisted solvothermal method.And the effects of water-to-surfactant ratio,reaction temperature and reaction time on the morphology and size of lanthanum oxide were investigated.The results showed that the synthesized of lanthanum oxide particles are rodlike.The size of the product increased,with the increasing of the water-to-surfactant ratio,reaction temperature,as well as reaction time.?3?The synthesized of La₂O₃ was modified with stearic acid and then applied to polyester dyeing.The effects of dyeing conditions on the dyeing rate of polyester were studied by orthogonal experiment.The results showed that when the reaction time was 50 min and the reaction temperature was 83 °C,the consumption of dye,acetic acid,dispersing agent and methyl salicylate to the polyester fabric quality were 1.5 %,0.5 %,0.5 % and 3.0 %,respectively,the dyeing rate reached to the maximum.The change of the dyes will not influence the dyeing effect.