Although it is estimated that Nature uses CO2 to produce more than 200 billion tons of glucose per year through a process photosynthesis, specialists in synthetic chemistry have made virtually no effect in the development of efficient catalytic processes that use this raw material is interesting. Activation and use carbon dioxide as a source of C1 little used, for example, in the field of organic synthesis from CO2 can realistically be done only urea, salicylic acid, as well as some cyclic carbonates. However, carbon gas can undergo copolymerization with heterocyclic compounds (epoxides, aziridines, episulfidy), which brings a series of new alternating copolymers. Of these, a very promising class of materials are polycarbonates, and they are thermoplastic materials, and they can be produced with reasonable efficiency of CO2 and epoxides. The first study showed that aliphatic polycarbonates can be treated with hydrolysis reactions, and in some cases, they are destroyed in vivo.

In 1969, Inoue announced a new way to create polycarbonates – sequential copolymerization of carbon dioxide and epoxides with zinc as a catalyst. This is a landmark discovery paved the way for the first time to use carbon dioxide as a source of large-scale synthesis of polycarbonate. The proposed series of copolymerization (Fig. 5) Lewis metal acid form of communication, and opens the epoxide ring, which generates metal alkoxides. Carbon dioxide is introduced in connection metal alkoxide, resulting in a metal carbonate, and this substance can form a bond and subsequent ring opening of epoxide molecules, repeating the cycle, ultimately leading to the formation of a polymer with high molecular weight.

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