Hexamethylene diisocyanate
| Hexamethylene diisocyanate | |
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1,6-diisocyanatohexane |
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Other names
HDI |
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| Identifiers | |
| CAS number | 822-06-0  |
| PubChem | 13192 |
| ChemSpider | 12637 |
| ChEBI | CHEBI:53578 |
| Jmol-3D images | Image 1 |
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| Properties | |
| Molecular formula | C8H12N2O2 |
| Molar mass | 168.2 g/mol |
| Appearance | Colourless liquid |
| Density | 1.047 g/cm3, liquid |
| Melting point |
-67 °C (206 K) |
| Boiling point |
255 °C (528 K) |
| Viscosity | 3 cP at 25 °C |
| Hazards | |
| Flash point | 130–140 °C (Cleveland open cup) |
| Related compounds | |
| Related isocyanates | Isophorone diisocyanate |
 (verify) (what is:  / ?)Except where noted otherwise, data are given for materials in their standard state (at 25 °C, 100 kPa) |
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| Infobox references | |
Hexamethylene diisocyanate (HDI) is an organic compound in the class known as isocyanates. More specifically, it is an aliphatic diisocyanate. It is produced in relatively small quantities, accounting for (with isophorone diisocyanate) only 3.4% of the global diisocyanate market in the year 2000.[1] Aliphatic diisocyanates are used in special applications, such as enamel coatings which are resistant to abrasion and degradation from ultraviolet light. These properties are particularly desirable in, for instance, the exterior paint applied to aircraft.
Contents |
[edit] Synthesis
There are two steps to the synthesis of pure HDI:[1]
- Phosgenation: Reaction of hexamethylene diamine with phosgene to form crude HDI
- Purification: Distillation of crude HDI to extract pure HDI
[edit] Chemistry
HDI is a symmetrical molecule and thus has two isocyanate groups of equal reactivity.
[edit] See also
[edit] References
- ^ a b Randall, David; Lee, Steve (2002). The Polyurethanes Book. New York: Wiley. ISBN 978-0-470-85041-1.
[edit] External links
- NIOSH Safety and Health Topic: Isocyanates, from the website of the National Institute for Occupational Safety and Health (NIOSH)
