Hybrid Organo-Inorganic Composites Based on Sea Urchin Skeleton and Organylsiloxane

In this work we studied the interaction of the sea urchin skeleton with polyethylsilsesquioxane to obtain composites and studied their properties. The composite was obtained by interaction of polyethylsilsesquioxane with the skeleton of a sea urchin at a ratio of 2:1 under the conditions of mechanochemical activation. When the composite is heated, the volatile cyclic products containing calcium and silicon are removed according to thermal analysis data in the range of 600–800 °C, the similar behavior of polyethylsilsesquioxane is observed in the temperature range of 400–600 °C. Further, polycalcium ethylsilsesquioxane was extracted by toluene extraction of composite, its composition and structure were confirmed by IR spectroscopy, XRD, gel-chromatography and thermogravimetric analysis. Polycalcium ethylsilsesquioxane has a mesomorphic structure; based on XRD the cross-sectional area of ​​the polymer was calculated, and it was found to be close to the cross-sectional area of ​​polyvinylsiloxane. A scheme of the interaction of calcite with siloxane was proposed where the main reaction is the interaction of the carboxy group of calcite with a siloxane bond, and was shown by electron microscopy the process of siloxane incorporation proceeds in layers confirming the layer-by-layer arrangement of the pores of the sea urchin skeleton. The urchin skeleton treated with polycalcium ethylsilsesquioxane has a layered structure. Treatment of the urchin skeleton with polycalcium ethylsilsesquioxane after heating at 400–600 °C leads to the formation of a ceramic composite the structure of which repeats the structure of the urchin skeleton, while the effect of hydrochloric acid does not significantly affect the composite structure.