Heteropoly Acid / Preparation, Characterization And Properties Of Pva Microfiber

1. PVA ultra-fine fiber mats, which contained different concentrations of K8SiW11O39, H3PW11MoO40 or H4SiW12O40, were prepared by electrospining technique and characterized by Fourier transform-infrared spectroscopy, X-ray diffractometry methods and scanning electron microscopy. The regularity of the fiber materials facies' variability was explained by means of the concentration, viscosity and conductivity of the solution.2.PVA ultra-fine fiber mat contained 60% H3PW11MoO40, H4SiW12O40 was irradiated under 313 nm ultraviolet light. The photochromism was studied and the reaction mechanism was presented according to electron paramagnetic resonance spectrum. The fiber fragmentation was discovered after the PWnMo/PVA, H4SiW12O4o fiber mats were irradiated under, simultaneously the fiber mats turned to thinner. It was supposed that the existing of heteropolyacid was beneficial to the photodegradation of PVA.3. PVA ultra-fine fiber mat contained 50% K5SiWnAl(H2O)O39 was prepared by electrospining technique and characterized by Fourier transform-infrared spectroscopy. X-ray diffractometry methods and scanning electron microscopy. The fiber mats contained 50% K5SiW11Al(H2O)O39 and 60% H3PW11MoO40, H4SiW12O40 were calcined under the definited temperature, respectively, and the pure polyoxometallates K5SiWnAl(H2O)O39 ultra-fine particle and pure heteropolyacid H3PW11MoO40 and H4SiW12O40 ultra-fine fiber were obtained and characterized by Fourier transform-infrared spectroscopy, X-ray diffractometry methods and scanning electron microscopy. Two-roasted conformation was compared to each other and the explanation was given.4. The catalysis property of cyclohexene oxidation reaction was investigated by using pure heteropolyacid and calcined heteropolyacid as catalyzer.