Toluene diisocyanate (TDI), CAS 584-84-9, is the leading aromatic isocyanate used to make flexible polyurethane foam. The most common commercial grade is TDI 80/20, an 80:20 mixture of 2,4- and 2,6-TDI isomers.

Key Specifications

• Molecular Formula: C₉H₆N₂O₂

• Appearance: Clear, pale-yellow liquid

• NCO Content: ~48%

• Viscosity: ~3 mPa·s at 25°C

• Isomer Ratio: 80:20 (standard)

• Packaging: 250 kg drums, 1,000 kg IBCs, bulk

TDI is moisture-sensitive. It reacts with water and must be stored under dry nitrogen between 15–35°C. Shelf life is about 12 months under proper conditions.

Main Applications

• Flexible foam: mattresses, sofas, pillows, automotive seats

• CASE systems: coatings, adhesives, sealants, elastomers

• Specialty uses: synthetic leather, coated fabrics, rubber binders

TDI 80/20 is preferred for slabstock and molded foam because of its fast cure, low viscosity, and consistent reactivity.

Safety and Handling

TDI is hazardous. Inhalation is the main exposure risk and can cause respiratory irritation, occupational asthma, and skin sensitization. The odor threshold is much higher than safe exposure limits—if you smell it, you are likely overexposed.

Required controls:

• OSHA PEL: 0.02 ppm ceiling

• NIOSH REL: 0.005 ppm TWA

• Use chemical-resistant PPE and supplied-air respirators when needed

• Store away from water, amines, acids, and oxidizers

Market and Sourcing

China dominates global TDI supply, with strong export growth in 2026. Prices have rebounded from 2025 lows, and supply availability can fluctuate due to plant maintenance. When sourcing TDI, check:

• Batch COA, SDS, and TDS

• NCO content, acidity, and hydrolyzable chloride

• REACH/TSCA compliance

• Supplier logistics and technical support

FAQ

Is TDI the same as MDI?
No. TDI is mainly for flexible foam; MDI is more common for rigid foam, adhesives, and elastomers.

What is TDI 80/20?
It is the standard isomer blend of 80% 2,4-TDI and 20% 2,6-TDI.

Conclusion

TDI CAS 584-84-9 remains essential for flexible polyurethane foam. Buyers should focus on spec consistency, safe handling, and reliable supply—not price alone.

Contact us for TDI 80/20 pricing, COA, or bulk supply.