Investigation of exchange reactions in liquid thiokols
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The influence of a number of compounds that are components of vulcanizing mixtures — sulfur, bases, salts and oxides of manganese, lead, and iron — on the rate of exchange processes in liquid dichlorodiethylformal Thiokols was investigated by the methods of turbidimetric titration and IR spectroscopy. Sulfur and especially bases not only sharply accelerate exchange processes, but also lead to structuration. At the same time, an appreciable depolymerizing effect of iron salts on liquid Thiokols is observed.
The step of initiation of exchange reactions in the mass is heterolytic cleavage of the polysulfide bonds of higher sulfide character contained in the liquid Thiokols, after which the process develops as an aggregate of reactions of substitution at the -S-S-, -Sx-, and -SH bonds. The activating effect of bases and free sulfur on exchange is explained in accord with the proposed scheme.
The data obtained are evidence of a relationship of exchange reactions in Thiokols with the process of vulcanization of this polymer.
KeywordsOxide Iron Polymer Sulfur Spectroscopy
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