cis - and trans -Isomers of the platinum(II) nitrile complexes [PtCl 2 (NCR) 2 ] (R = NMe 2 , N(C 5 H 10 ), Ph, CH 2 Ph) were examined as catalysts for hydrosilylation cross-linking of vinyl-terminated polydimethylsiloxane and trimethylsilyl-terminated poly(dimethylsiloxane- co -ethylhydrosiloxane) producing high quality silicone rubbers. Among the tested platinum species the cis -complexes are much more active catalysts than their trans -congeners and for all studied platinum complexes cis -[PtCl 2 (NCCH 2 Ph) 2 ] exhibits the best catalytic activity (room temperature, c = 1.0 × 10 −4 mol/L, τ pot-life 60 min, τ curing 6 h). Although cis -[PtCl 2 (NCCH 2 Ph) 2 ] is less active than the widely used Karstedt’s catalyst, its application for the cross-linking can be performed not only at room temperature ( c = 1.0 × 10 −4 mol/L), but also, more efficiently, at 80 °C ( c = 1.0 × 10 −4 –1.0 × 10 −5 mol/L) and it prevents adherence of the formed silicone rubbers to equipment. The usage of the cis - and trans -[PtCl 2 (NCR) 2 ] complexes as the hydrosilylation catalysts do not require any inhibitors and, moreover, the complexes and their mixtures with vinyl- and trimethylsilyl terminated polysiloxanes are shelf-stable in air. Tested catalysts do not form colloid platinum particles after the cross-linking.

The state of the production of low-molecular-mass rubbers and sealants on their basis in Russia is considered. The history of sealant development is described; organizations and scientists that made the largest contribution to the elaboration and industrial production of these materials are reported. Classification of sealants and the mechanism of their vulcanization are considered. The main attention is paid to materials developed at the All-Russia Institute of Aviation Materials. The sealant brands most widely used in the aircraft industry are presented and their properties are described. Prospective problems in the field of sealant development are considered and the ways of their solution are outlined.

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