Pathways Of Synthesis Of New Organosilicon Sorbents With Selected Properties
PATHWAYS OF SYNTHESIS OF NEW ORGANOSILICON SORBENTS WITH SELECTED PROPERTIES
Yu.N. Shevchenko1, S.N. Stadnyk2
1The Ukrainian International Academy of Original Ideas, Kiev, Ukraine
2CSC "Ecologoprotective company "КREOMA-PHARM", Kiev, Ukraine
Study of copolycondensation reactions in aqueous-alkaline medium of organosilicon monomers having a varying quantity and character of an organic radical R gives the possibility to vary a porous structure well as hydrophobic properties of resulting hydrogels and xerogels. Thus, large-pore sorbents with improved hydrophobic properties by copolycondensation of methyl – and dymethylsilanols taken in different proportions were prepared. Addition into the polycondensation solution up to 15 % of ethylsilanetriol allowed including 1-7 % of ethyl groups located on the surface of globule forming a matrix.
Another promising trend for producing porous globular sorbents is the synthesis of porous matrices with active groups located on the globular surface, which are capable of substitution, for example, such as ¾Н, ¾Cl, ¾Br, etc.
We carried out substitution reactions and as a result, have grafted to the surface in amount of 1-5% organic molecules-ligands capable of selective binding (complex formation) of ions of d-metals.
In our opinion, it is interesting to synthesize organosilicon matrices by means of copolycondensation of organosilanols with organosilicon compounds containing radicals of biologically active substances. It will make possible to increase a content of active centers in the matrix as well as to vary it by hydrophilic-hydrophobic properties, pore dimension, selectivity in relation to different classes of organic substances. In this connection, it is realistic to design
sorbents with inserted porphirin iron (II) complexes modeling by its structure Heme of hemoglobin, which are able to bind a molecular oxygen reversibly.
New possibilities for synthesis of selective sorbents are opened up by the combining introduction of ions of Al3+, Ti4+ and others into globules, which are preferably the centers of a bidentate binding of transition metal ions, and by grafting of ligand groups in the above mentioned reactions capable of letting the 5th and/or 6th place of binding these ions. Using this method, there have been prepared sorbents with inserted complexes of Fe2+ and Cu2+ ions, modeling centers of binding of a number enzymes.
The study presents data on structure-sorption characteristics of a series of synthesized sorbents, their physicochemical and spectral properties.
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