Hexamethylene diisocyanate

Chembox new
Name = Hexamethylene diisocyanate
ImageFile = Hexamethylene-diisocyanate-2D-skeletal.png ImageName = Hexamethylene diisocyanate
ImageFile1 = Hexamethylene-diisocyanate-3D-vdW.png ImageName1 = Hexamethylene diisocyanate
IUPACName = 1,6-diisocyanatohexane
OtherNames = HDI
1,6-hexane diisocyanate
Section1 = Chembox Identifiers
SMILES = O=C=NCCCCCCN=C=O
CASNo = 822-06-0
RTECS =
Section2 = Chembox Properties
Formula = C₈H₁₂N₂O₂
MolarMass = 168.2 g/mol
Appearance = Colourless liquid
Density = 1.047 g/cm³, liquid
Solubility =
MeltingPt = -67 °C (206 K)
BoilingPt = 255 °C (528 K)
pKa =
pKb =
Viscosity = 3 cP at 25 °C
Section3 = Chembox Structure
MolShape =
Coordination =
CrystalStruct =
Dipole =
Section7 = Chembox Hazards
ExternalMSDS =
MainHazards =
FlashPt = 130–140 °C (Cleveland open cup)
RPhrases =
SPhrases =
Section8 = Chembox Related
OtherAnions =
OtherCations =
Function = isocyanates
OtherFunctn = Isophorone diisocyanate
OtherCpds =

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.cite book | first=David | last=Randall | coauthors=Lee, Steve | title=The Polyurethanes Book | publisher=Wiley | location=New York | year=2002 | id=ISBN 978-0-470-85041-1] 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.

ynthesis

There are two steps to the synthesis of pure HDI:
* "Phosgenation:" Reaction of hexamethylene diamine with phosgene to form crude HDI
* "Purification:" Distillation of crude HDI to extract pure HDI

Chemistry

HDI is a symmetrical molecule and thus has two isocyanate groups of equal reactivity.

ee also

* Methylene diphenyl diisocyanate
* Toluene diisocyanate

References

External links

* [http://www.cdc.gov/niosh/topics/isocyanates/ NIOSH Safety and Health Topic: Isocyanates] , from the website of the National Institute for Occupational Safety and Health (NIOSH)