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Table 1 Structures for the most commercially important isocyanates. Also presented is CAS number, molecular weight and other physico-chemical properties, such as melting point, boiling point and vapour pressure as well as solubility and main commercial uses

From: The role of isocyanates in fire toxicity

Compound CAS number Molecular weight (g · mol−1) Structure Melting point (°C) Boiling point (°C at 760 mmHg) Vapour pressure (mmHg at 25 °C) Solubility Commercial use
Isocyanic acid (ICA) 75-13-8 43.03 −86 17 6752.5 Water, benzene, toluene, ether  
Methyl isocyanate (MIC) 624-83-9 57.05 −45 39 348 Water Chemical intermediate
Ethyl isocyanate (EIC) 109-90-0 71.08 −50 60 209.5 Soluble in ethanol, ether, chlorinated and aromatic hydrocarbons as well as water Chemical intermediate
Propyl isocyanate (PIC) 110-78-1 85.10 −30 83 83.9 Insoluble in water  
Phenyl isocyanate (PHI) 103-71-9 119.12 −30 163 2.1 Water, alcohol; very soluble in ether Chemical intermediate
Hexamethylene di-isocyanate (HDI) 822-06-0 168.19 −67 255 0.0 Water Coatings
Toluene di-isocyanate (2,4-TDI) 584-84-9 174.16 20 251 0.0 Very soluble in ether. acetone, and other organic solvents PUF, PUR
Toluene di-isocyanate (2,6-TDI) 91-08-7 174.16 18 248 0.0 Soluble in acetone, benzene, decomposes in water PUF, PUR
Methylene bisphenyl di-isocyanate (MDI) 101-68-8 250.25 38 373 0.1 Soluble in acetone, benzene, kerosene, and nitrobenzene, decomposes in water PUR, PIR
Isophorone di-isocyanate (IPDI) 4098-71-9 222.28 −60 158 0.0 Soluble in esters, ketones, ethers, and aromatic and aliphatic hydrocarbons. Decomposes in water Crosslinking agent, coatings