The application dimension of the Diphenylmethane Diisocyanate Polyurethane (MDI Polyurethane) market is dominated by five principal end‑use categories. Construction—including thermal insulation panels, roofing membranes, and structural coatings—accounts for roughly 40 % of total revenue, reflecting the material’s high fire‑rating and durability. Automotive applications, such as seat cushion foams, interior trim, and impact‑absorbing structures, contribute about 25 % as manufacturers pursue weight reduction and acoustic performance. Furniture and office‑fitout foams, primarily used in upholstered seating and mattresses, represent an estimated 15 % share, driven by consumer demand for comfort and recyclability. Appliances—refrigerator insulation, washing‑machine dampers, and HVAC components—hold close to 10 % of the market, leveraging MDI’s low thermal conductivity. The residual 10 % is classified as others, encompassing marine, aerospace, and specialty adhesives. This application‑based taxonomy clarifies how each sector underpins the overall market size and informs strategic allocation of R&D resources. Geographically, these application shares are relatively consistent across North America, Europe, and Asia‑Pacific, although emerging construction projects in the latter region are accelerating its growth trajectory.