Hexamethylene diisocyanate

Synonyms & Trade Names

1,6-Diisocyanatohexane, HDI, Hexamethylene-1,6-diisocyanate, 1,6-Hexamethylene diisocyanate, HMDI

CAS No.

822-06-0

RTECS No.

MO1740000

DOT ID & Guide

2281 156

Formula

OCN[CH₂]₆NCO

Conversion

1 ppm = 6.88 mg/m³

IDLH

N.D.
See: IDLH INDEX

Exposure Limits

NIOSH REL

TWA 0.005 ppm (0.035 mg/m³) C 0.020 ppm (0.140 mg/m³) [10-minute]

OSHA PEL

none

Measurement Methods

NIOSH 5521 , 5522 , 5525;
OSHA 42
See: NMAM or OSHA Methods

Physical Description

Clear, colorless to slightly yellow liquid with a sharp, pungent odor.

Molecular Weight

168.2

Boiling Point

415°F

Freezing Point

-89°F

Solubility

Low (Reacts)

Vapor Pressure

(77°F): 0.05 mmHg

Ionization Potential

Specific Gravity

(77°F): 1.04

Flash Point

284°F

Upper Explosive Limit

Lower Explosive Limit

Class IIIB Combustible Liquid: Fl.P. at or above 200°F.

Incompatibilities & Reactivities

Water, alcohols, strong bases, amines, carboxylic acids, organotin catalysts [Note: Reacts slowly with water to form carbon dioxide. Avoid heating above 392°F (polymerizes).]

Exposure Routes

inhalation, ingestion, skin and/or eye contact

Symptoms

irritation eyes, skin, respiratory system; cough, dyspnea (breathing difficulty), bronchitis, wheezing, pulmonary edema, asthma; corneal damage, skin blisters

Target Organs

Eyes, skin, respiratory system

Personal Protection/Sanitation

(See protection codes)
Skin:Prevent skin contact
Eyes:Prevent eye contact
Wash skin:When contaminated
Remove:When wet or contaminated
Change:No recommendation
Provide:Eyewash, Quick drench

First Aid

(See procedures)
Eye:Irrigate immediately
Skin:Soap flush immediately
Breathing:Respiratory support
Swallow:Medical attention immediately

Respirator Recommendations

NIOSH

Up to 0.05 ppm:
(APF = 10) Any supplied-air respirator*

Up to 0.125 ppm:
(APF = 25) Any supplied-air respirator operated in a continuous-flow mode*

Up to 0.25 ppm:
(APF = 50) Any self-contained breathing apparatus with a full facepiece
(APF = 50) Any supplied-air respirator with a full facepiece

Up to 1 ppm:
(APF = 2000) Any supplied-air respirator that has a full facepiece and is operated in a pressure-demand or other positive-pressure mode

Emergency or planned entry into unknown concentrations or IDLH conditions:
(APF = 10,000) Any self-contained breathing apparatus that has a full facepiece and is operated in a pressure-demand or other positive-pressure mode
(APF = 10,000) Any supplied-air respirator that has a full facepiece and is operated in a pressure-demand or other positive-pressure mode in combination with an auxiliary self-contained positive-pressure breathing apparatus

Escape:
(APF = 50) Any air-purifying, full-facepiece respirator (gas mask) with a chin-style, front- or back-mounted organic vapor canister
Any appropriate escape-type, self-contained breathing apparatus

Important additional information about respirator selection

Hexamethylene diisocyanate

NIOSH REL

OSHA PEL

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