Toluene Diisocyanate (TDI)

Description

Toluene diisocyanate (TDI) is an organic compound with the formula CH3C6H3(NCO)2. Two of the six possible isomers are commercially important:

• 2,4-TDI (CAS: 584-84-9) and
• 2,6-TDI (CAS: 91-08-7).

2,4-TDI is produced in the pure state, but TDI is often marketed as 80/20 and 65/35 mixtures of the 2,4 and 2,6 isomers respectively.

It is produced on a large scale, accounting for 34.1% of the global isocyanate market in 2000, second only to MDI. Approximately 1.4 billion kilograms were produced in 2000. All isomers of TDI are colorless, although commercial samples can appear yellow.

Applications

Toluene diisocyanate (TDI) is used in the production of flexible polyurethane foam and other polyurethane applications including elastomers, synthetic leather, coated fabrics, paints, and adhesives.