Magnetic materials based on iron-silicon containing frameworks

Polyferrophenylsiloxanes based on iron(III) chelate and polyphen-ylsiloxane with various ratios of siloxane and sodium hydroxide under mechanochemical activation conditions have been obtained. It is shown that after precipitation with petroleum ether, the yields of polymers are in the range of 37-52%. The polyferrophenylsiloxane composition closest to the given composition was obtained at a Si : Na ratio of 1. The obtained compo-sites were studied by IR spectroscopy, diffractometry, gel chromatography, and thermogravimetry. An XRD study showed the incorporation of iron at-oms into the siloxane structure. The presence of sodium ions during the course of the reaction in subsequent syntheses made it possible to bind the released acetylacetone and obtain polyferrophenylsiloxane with a given Si : Fe ratio. However, with a further increase in the hydroxide content, the Si : Fe ratio was violated. The study of the magnetic properties of polyferro-phenylsiloxanes showed that they are superparamagnets. After heating them to 600°C, the magnetization sharply increases (magnetic saturation) and hysteresis is observed.