The Study on the Preparation Technique and the Basic Physical Properties of Polyvinyl Alcohol (PVA) Carrier of CoFe_2O_4 Magnetic Fluid and CoFe_2O_4 Magnetic Fluid PVA Coated

Abstract: This paper introduce the preparation technique of Polyvinyl alcohol (PVA) carrier of CoFe_2O_4 magnetic fluid and CoFe_2O_4 magnetic fluid PVA coated.We study particle size measurement .the basic physical character such as density .stability, the viscosity of magnetic fluid in zero magnetic field and property of magnetization, the field -induced transmission light of self-formed ferrofluid has been studiedOn the base of chemical coprecipitated method ,we prepare Polyvinyl alcohol (PVA ) carrier of CoFe_2O_4 magnetic fluid by coprecipitated and acid erode method. CoFe_2O_4 magnetic fluid PVA coated by coated surfactants method.Using DLVO theory analyze the factors which influence the fluids stability We measure viscosities of liquids that have different volume ratios and the viscosity of magnetic fluid of which magnetic particle'volume ration or carrier's volume ratioφ_s being certain in zero magnetic field. Through comparing the experiment results on various conditions, we study the carrier's viscosity and magnetic particles volume ration's affections on the magnetic fluid's viscosity Then we try to explain the phenomena andη~φcurves of the experiment.The magnetic behavior of Polyvinyl alcohol (PVA) carrier of CoFe_2O_4 magnetic fluid and CoFe_2O_4 magnetic fluid PVA coated is measured at room temperature .the result show the saturation magnetization of CoFe_2O_4 magnetic fluid PVA coated is less than Polyvinyl alcohol (PVA) carrier of CoFe_2O_4 magnetic fluid which has the sameφ_v andφ_s due to the different thickness of surface which has no magnetic. and this two fluids is supermagnetism.At last we study the distribution of the magnetic field between two solenoids by experiment, and calculate the gradient of magnetic induction between two solenoids. this paper introduces the transmission intensity of light through magnetic liquids under different magnetic fields which parallel to the light direction ,we analyze the course of these phenomena and discuss how the magnetic nanoparticles move under different magnetic fields…
Key words: Ferrofluids; coated; Saturation magnetization; Field-induced transmitted light

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