Novel one-pot polymer syntheses based on dithiols obtained from a five-membered cyclic dithiocarbonate and diamines

Novel one-pot syntheses of sulfur-containing polymers from a five-membered cyclic dithiocarbonate (5-phenoxymethyl-1,3-oxathiolane-2-thione ( 1 )) and diamines were examined. Polydisulfides with M̄_n 5400 ∼ 15800 were obtained in the oxidation polymerization of dithiols 2 , which were obtained in situ by the reactions of 1 and diamines. When 1,12-dodecanediamine was employed, a polydisulfide with relatively high M̄_n was obtained, while in the case of m-xylylenediamine, the polymerization was accompanied by intermolecular cyclization to give a polydisulfide with low M̄_n. Polythiourethanes with M̄_n 6500 ∼ 17200 were obtained in the polyaddition of 2 with 4,4′-methylenebis(phenyl isocyanate). The yields and M̄_n values increase with increasing methylene chain length of 2 . Polythioethers with M̄_n 2600 ∼ 19900 were obtained by the polycondensations of 2 with α,α′-dibromo-p-xylene. The glass transition temperature (T_g) of the polymer decreases with increasing methylene chain length in the main chain.