Methylene diphenyl diisocyanate

4,4′-Methylene diphenyl diisocyanate
4,4'-methylene diphenyl diisocyanate
Names
Preferred IUPAC name
1,1′-Methylenebis(4-isocyanatobenzene)
Other names
  • Bis(4-isocyanatophenyl)methane
  • 1-Isocyanato-4-[(4-isocyanatophenyl)methyl]benzene
  • 4,4′-Methylene diphenyl diisocyanate
  • 4,4′-Diphenylmethane diisocyanate
  • Bayer Desmodur 44
  • Methylene bis(4-phenyl isocyanate)
  • Pure MDI
Identifiers
3D model (JSmol)
ChEBI
ChemSpider
ECHA InfoCard 100.043.361 Edit this at Wikidata
EC Number
  • 4,4'-: 202-966-0
RTECS number
  • NQ9350000
UNII
  • InChI=1S/C15H10N2O2/c18-10-16-14-5-1-12(2-6-14)9-13-3-7-15(8-4-13)17-11-19/h1-8H,9H2 ☒N
    Key: UPMLOUAZCHDJJD-UHFFFAOYSA-N ☒N
  • O=C=NC(C=C2)=CC=C2CC1=CC=C(N=C=O)C=C1
  • O=C=N\c1ccc(cc1)Cc2ccc(\N=C=O)cc2
Properties
C15H10N2O2
Molar mass 250.25 g/mol
Appearance White or pale yellow solid
Density 1.230 g/cm3, solid
Melting point 40 °C (104 °F; 313 K)
Boiling point 314 °C (597 °F; 587 K)
Reacts
Vapor pressure 0.000005 mmHg (20 °C)[1]
Hazards
GHS labelling:
GHS07: Exclamation markGHS08: Health hazard
Danger
H315, H317, H319, H332, H334, H335, H351, H373
P201, P202, P260, P261, P264, P271, P272, P280, P281, P285, P302+P352, P304+P312, P304+P340, P304+P341, P305+P351+P338, P308+P313, P312, P314, P321, P332+P313, P333+P313, P337+P313, P342+P311, P362, P363, P403+P233, P405, P501
Flash point 212–214 °C (Cleveland open cup)
Lethal dose or concentration (LD, LC):
2200 mg/kg (mouse, oral)[2]
31,690 mg/kg (rat, oral)[2]
  • 369 mg/m3 (rat, 4 hr)
  • 380 mg/m3 (rat, 4 hr)
  • 178 mg/m3 (rat)[2]
NIOSH (US health exposure limits):
PEL (Permissible)
C 0.2 mg/m3 (0.02 ppm)[1]
REL (Recommended)
TWA 0.05 mg/m3 (0.005 ppm) C 0.2 mg/m3 (0.020 ppm) [10-minute][1]
IDLH (Immediate danger)
75 mg/m3[1]
Related compounds
Related Isocyanates
Related compounds
Polyurethane
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
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Methylene diphenyl diisocyanate (MDI) is an aromatic diisocyanate. Three isomers are common, varying by the positions of the isocyanate groups around the rings: 2,2′-MDI, 2,4′-MDI, and 4,4′-MDI. The 4,4′ isomer is most widely used, and is also known as 4,4′-diphenylmethane diisocyanate.[3] This isomer is also known as Pure MDI. MDI reacts with polyols in the manufacture of polyurethane. It is the most produced diisocyanate, accounting for 61.3% of the global market in the year 2000.[4]

  1. ^ a b c d NIOSH Pocket Guide to Chemical Hazards. "#0413". National Institute for Occupational Safety and Health (NIOSH).
  2. ^ a b c "Methylene bisphenyl isocyanate". Immediately Dangerous to Life or Health Concentrations (IDLH). National Institute for Occupational Safety and Health (NIOSH).
  3. ^ Pubchem. "4,4'-Diphenylmethane diisocyanate | C15H10N2O2 - PubChem". pubchem.ncbi.nlm.nih.gov. Retrieved 2017-06-25.
  4. ^ Randall, D.; Lee, S. (2003). The Polyurethanes Book. New York: Wiley. ISBN 978-0-470-85041-1.