Propylene Carbonate → Isophorone DI-isocyanate

Participants

Reaction Conditions

Reaction Steps

A mixture of 861 parts of isophorone diisocyanate, 535.95 parts of propylene carbonate and 2.15 parts of Dabco TMR* is stirred and gradually heated. When the temperature reaches 55° C. heating is discontinued. The exothermic reaction raises the temperature to 131° C. in 15 minutes. After cooling to 89° C., 5.8 parts of a 10% solution of Dabco TMR* in propylene carbonate is added. The temperature rises to 90° C. in 8 minutes. After heating to 132° C. it is allowed to cool. 1397.1 parts of this product, the tri-isocyanato-isocyanurate formed from 3 moles of isophorone di-isocyanate as a 61.4% solids solution in propylene carbonate, having an NCO content of 10.94% is stirred while 366.8 parts of 3,5-dimethylpyrazole is added, cooling as required, to keep the temperature below 80° C. followed by 463.4 parts of the monomethyl ether of propylene glycol. The mixture is stirred at 50° C. and a clear solution formed which solution is then allowed to cool. The IR Spectrum shows NCO absent.

Provenance & Evidence