Isotsyanatti

Isotsyanatti is a chemical group characterized by the functional group -N=C=O. This group is known for its high reactivity, particularly with nucleophiles containing active hydrogen atoms. This reactivity is the basis for many of its important applications.

The most common and commercially significant isocyanates are diisocyanates, which contain two isocyanate groups. These compounds are essential building blocks for polyurethanes, a versatile class of polymers. Polyurethanes find widespread use in foams (flexible and rigid), coatings, adhesives, sealants, and elastomers. The properties of the resulting polyurethane can be tailored by selecting different diisocyanates and polyols (compounds with multiple hydroxyl groups).

Common examples of diisocyanates include toluene diisocyanate (TDI) and methylene diphenyl diisocyanate (MDI). TDI is primarily used in flexible polyurethane foams for furniture and automotive seating, while MDI is used in rigid foams for insulation in construction and appliances, as well as in coatings and adhesives.

While incredibly useful, isocyanates are also known for their toxicity. They can be respiratory irritants and sensitizers, meaning repeated exposure can lead to asthma-like symptoms. Proper handling procedures, ventilation, and personal protective equipment are crucial when working with isocyanates. Workplace exposure limits are established to minimize health risks.