TDI – MDI

TDI 80/20 – Toluene Diisocyanate

Toluene Diisocyanate TDI 80-20 is a toxic and highly reactive organic compound.

The chemical formula for TDI is CH3C6H3(NCO)2. TDI is often marketed as TDI 80/20.

TDI 80-20 is a mixed blend of 80% 2,4-toluene diisocyanate and 20% 2,6-toluene diisocyanate. The clear to pale yellow liquid organic compound is toxic, has a sharp odor, and is highly reactive. It is used in the manufacture of polyurethane flexible foam (slab/molding) and non-foam urethanes.

Toluene diisocyanate (TDI) is a member of isocyanates which are chemically related to Polyurethanes. Two of the six possible isomers are commercially important: 2,4-TDI and 2,6-TDI. 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. TDI is  80:20 mixture of the 2,4 and 2,6 isomers with the purity of at least 99.5%.

Applications
Toluene Diisocyanate TDI 80-20 is an aromatic isocyanate that is produced for reaction with polyols to form polyurethanes. It is widely used in the production of polyester-based soft foam, high-bearing sponges, semi-rigid ester foam, and paint.

4,4’-methylene diphenyl diisocyanate

Chemical name of the compound: 1,1’-methylenebis(4-isocyanatobenzene)

Synonyms: MDI, Bis(4-isocyanatophenyl)methane, 1-Isocyanato-4-[(4-isocyanatophenyl)methyl]benzene, 4,4′-Diphenylmethane diisocyanate, methylene bis(4-phenyl isocyanate).

Chemical and physical properties: White to light yellow solid, water reactive. Undergoes rapid reaction with alcohols, acids, bases or oxidatives. May polymerize in temperaturę above 200 °C.

Application: Production of rigid polyurethane foams, glues.