Isocyanates structure

Polymerization (76MI11100) of the maleimide isomer 5-(l-adamantyloxy)-2//-pyrrol-2-one (11) allows incorporation (Scheme 6) of the 4-pyrrolin-2-one ring system into a polymeric framework. In analogy with model compounds, polymers and copolymers containing the structural unit (12) undergo photochemical rearrangement to the isocyanate structure (13). Thermolysis, on the other hand, produces poly(maleimides) (14). 

The weakness of this formula lies in the fact that the only available evidence on the subject points to the conclusion that the iron is attached directly to nitrogen, and not to the carbon as here represented, ferrous cyanide having the isocyanic structure.2... 

The high isocyanate index of catalyst system will promote the formation of isocyanate structures. 

The higher heat stability of the isocyanate structures will be enhanced by a fire-retardant grade of polyol. 

Seefried C, Koleske J, Critchfield F. Thermoplastic urethane elastomers, m. Effects of variations in isocyanate structure. J Appl Polym Sci 1975 19(12) 3185-91. 

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