Desmodur® E 21 

Desmodur® E 21 is an aromatic polyisocyanate prepolymer based on diphenylmethane diisocyanate (MDI). It is a solvent-free liquid of medium viscosity. It is suitable for use in the formulation of moisture-curing, one-component systems which, when thinned with a suitable solvent, can be used as primers and sealers for porous substrates to provide protection against moisture, oil, fuel and other chemicals. It can also be used as a binder in the formulation of synthetic resin mortars.




Covestro (formerly Bayer MaterialScience) manufactures adhesive raw materials for use in the production of contact and heat-activated adhesives, as well as reactive and hot-melt adhesives for the transportation, furniture, footwear, packaging, and construction markets. Bayer offers a comprehensive range based on polyurethane and polychloroprene, with specialty raw materials that offer UV light and weather resistance.

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Covestro (formerly Bayer MaterialScience)

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The information presented here was acquired by UL from the producer of the material.  UL makes substantial efforts to assure the accuracy of this data.  However, UL assumes no responsibility for the data values and strongly encourages that upon final material selection data points are validated with the material supplier.