Methylenediphenyl diisocyanate (MDI) is a chemical compound commonly used in the production of polyurethane foams, coatings, and adhesives. It is a type of diisocyanate, which means it contains two isocyanate groups that react with polyols to create versatile polymer materials. MDI is known for its durability and resistance to heat and chemicals. MDI is typically produced through the reaction of aniline and formaldehyde, resulting in a mixture of isomers. It is widely used in various industries, including construction, automotive, and furniture manufacturing, due to its excellent mechanical properties and insulation capabilities. Safety precautions are essential when handling MDI, as it can be hazardous if inhaled or in contact with skin.