Analyze the widespread use of ferrocene-based polymers in various fields of science. Describe the methods of synthesis of ferrocene-based polymers.

We list the real directions of the industrial use of ferrocene (more than 2000 papers have been published on the industrial use of ferrocene). Such a range of studies of the applied properties of ferrocene is due to the peculiarities of its physical and chemical properties: unusually high for an organometallic compound, thermal stability, high vapor pressure, low toxicity, good solubility in organic solvents, and, most importantly, a wealth of chemical transformations.

1. The regulation of combustion processes by ferrocene compounds is based on the formation of catalytically active particles as a result of the decomposition of the ferrocene sandwich system. These particles are the smallest particles of zero-valent iron, particles a-iron oxide and organic radicals

Such particles contribute to:

J additional branching chain reactions;

J more efficient transfer of oxygen to oxidizable molecules due to the transfer of oxygen to the active atomic state.

2. Ferrocene-based polymers have many valuable characteristics. Of these, the most important are: a) the ability to produce highly thermostable polymers and b) to have polymers having interesting electro- and magneto-physical characteristics. The latter property is based on the fact that ferrocene acquires an electric charge as it goes into ferrocenium (that is, an oxidized state), and also (due to the appearance of an unpaired electron) a magnetic moment and begins to manifest itself as an elemental magnet. Polymers with a mixed state of oxidation of iron have semiconductor properties.

Let us return, however, to thermostable polymers. Basically, they are obtained now on the basis of vinylferrocene (C5H5) Fe (C5H4-CH = CH2) and ferrocenyl acetylene (C5H5) Fe (C5H4-C╞CR). The first is polymerized mainly with styrene, and the second with isoprene. The copolymer molecule with styrene is as follows:

The content of ferrocene in the above copolymers is approximately 10-15 mol. % This is enough to increase the thermal stability of the original homopolymer by about 50-100? C.

3. For many years of studying ferrocene, there have been a lot of proposals for the use of its derivatives in fine organic synthesis. However, as a rule, for each useful offer there was another, but without the use of ferrocene, which solved a similar organic synthetic problem in a cheaper and more efficient way.

But one synthetic application has found a valid application - these are ferrocene derivatives containing phosphine groups, used as ligands for the synthesis of new metal-complex compounds. These complexes, as a rule, have catalytic activity in various polymerization and other industrially important processes. Ferrocene here is a strong and specific matrix that rigidly fixes the phosphorus atoms in the desired positions:

The use of one or another skeleton as a matrix for the proper spatial arrangement of functional groups is, apparently, the most important strategy for the synthesis of new molecules, and therefore the realization of new properties.

4. The use of the electrochemical properties of ferrocene is based on the ease and reversibility of the processes of single-electron oxidation or reduction (redox process).

(C5H5) 2Fe0 (C5H5) 2Fe +

The ferrocene-cation ferrocenium system is one of the most highly reversible redox systems known to mankind. Very successful was the use of this property in practice. First, as reversible electrodes for chemical analytical purposes (no less than 150 papers are devoted to this area alone), and second, as an effective electron carrier in various systems and, above all, in biochemical studies.

5. Continuing the biochemical topic, we note that today the complex ferrocene-containing compounds find diverse applications in biochemical and histological studies. Ferrocene and its oxidized form - ferrocenium have low toxicity and at the same time are an excellent color and redox-active label, easily attached to many biologically important molecules.

Ferrocene-based direct drugs have also been proposed, for example, ferroceron (ferroceronum) C5H5Fe [C5H5COC6H4-ortho-COONa] for the treatment of diseases caused by iron deficiency in the body.

6. Of the other applications of ferrocene, let us point out the production of photosensitive materials, dyes and pigments, as well as antistatic agents, monomer stabilizers and liquid crystals.

In conclusion, I would like to draw the reader’s attention to what a surprisingly beautiful and useful chemical creation was born by a human genius. The development of this area required incredible work, deep knowledge and creative, creative imagination. It remains for the reader to believe in the word that over the past 45 years a whole galaxy of prominent chemists of the world worked in this area.