Glossary of terms used in the polyurethanes business

Courtesy of Smithers-Rapra & Cromar Solutions Ltd, UK

 

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MDA An abbreviation for 2,2' / 2,4' and 4,4' Methylenedianiline. MDA is a chemical intermediate in the synthesis of certain isocyanates and polyurethane polymers.

MDI An abbreviation for 2,2' / 2,4' and 4,4'- Methylene diphenyl diisocyanate. MDI is an aromatic isocyanate and a key polyurethane raw material.

Microcellular An elastomer of cellular structure having a density between about 0.3 and 1.0 g/ml.

Mixing head A device, usually attached to liquid metering arrangements, which intimately mixes two or more components of a polyurethane reaction formulation.

Molecular weight The sum of the atomic weights of all the atoms in a molecule. Each atom has an atomic weight, which is related to its mass compared with that of one atom of carbon-12 (mass =12).

Monomer A substance which is capable of conversion into a polymer.

Mould Enclosure, often metal, in which a polyurethane mixture reacts to give a shaped article.