Diurethane system

More indirect support comes from the observation that at least one non-sulfur vulcanization system for NR does not result in adequate adhesion to RFL treated textiles. When rubber was crosslinked with a diisocyanate-nitrosophenol adduct (or diurethane" system),... 

Early in the investigations of the diurethane systems it was noted that improved cure efficiency could be achieved through the... 

System No. 5 displayed monotonic change of NCO group content with diurethane formation, shown by the appearance of NH bands at 1530 cm, amide III bands at 1220 cm, and CO absorption bands at 1735 cm. ... 

Essentially the same catalytic system has also been used by others [51, 52]. The FeCla amount was lower and the selectivity remained high, but the catalytic ratio was only 50. Soluble palladium complexes were postulated as the active species. 2,4 - and 4,4 -dinitrodiphenylmethane can also be efficiently carbonylated to the corresponding diurethane (a precursor to the important diisocyanate monomer MDI) by the same catalytic system [53, 54]. Cyclohexanol can also be used in place of ethanol [55]. 

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