Diizocyanates

Diisocyanates are a class of organic compounds characterized by the presence of two isocyanate functional groups (-N=C=O). These molecules are highly reactive, particularly with compounds containing active hydrogen atoms, such as alcohols, amines, and water. This reactivity is the basis for their widespread use in the production of polyurethane materials. Polyurethanes are versatile polymers found in a vast array of products including foams, coatings, adhesives, sealants, and elastomers.

The most common diisocyanates are toluene diisocyanate (TDI) and methylene diphenyl diisocyanate (MDI). TDI is typically used in the production of flexible polyurethane foams, often found in furniture and bedding. MDI is predominantly used in rigid polyurethane foams, which provide insulation in construction and appliances, as well as in coatings and adhesives.

Diisocyanates are generally produced through the phosgenation of diamines. The handling and use of diisocyanates require strict safety precautions due to their potential health hazards. Inhalation of diisocyanate vapors or aerosols can cause respiratory irritation, asthma, and sensitization. Skin contact can lead to irritation and allergic reactions. Therefore, appropriate personal protective equipment and ventilation are essential when working with these chemicals. Their reactive nature also necessitates careful storage and transportation to prevent unwanted reactions.