Skip directly to local search Skip directly to A to Z list Skip directly to navigation Skip directly to site content Skip directly to page options
CDC Home

Enter search terms separated by spaces.

Methylene bis(4-cyclohexylisocyanate)

Synonyms & Trade Names
Dicyclohexylmethane 4,4'-diisocyanate; DMDI; bis(4-Isocyanatocyclohexyl)methane; HMDI; Hydrogenated MDI; Reduced MDI; Saturated MDI
CAS No.
5124-30-1
RTECS No.
NQ9250000
DOT ID & Guide
Formula
CH2[(C6H10)NCO]2
Conversion
1 ppm = 10.73 mg/m3
IDLH
N.D.
See: IDLH INDEX
Exposure Limits
NIOSH REL
: C 0.01 ppm (0.11 mg/m3)
OSHA PEL
†: none
Measurement Methods

NIOSH 5525;
OSHA PV2092
See: NMAM or OSHA Methods
Physical Description
Clear, colorless to light-yellow liquid.
MW:
262.4
BP:
?
FRZ:
<14°F
Sol:
Reacts		 VP(77°F): 0.001 mmHg
IP:
?
Sp.Gr(77°F): 1.07
Fl.P:
>395°F
UEL:
?
LEL:
?
Class IIIB Combustible Liquid: Fl.P. at or above 200°F.
Incompatibilities & Reactivities
Water, ethanol, alcohols, amines, bases, acids, organotin catalysts [Note: May slowly polymerize if heated above 122°F.]
Exposure Routes
inhalation, ingestion, skin and/or eye contact
Symptoms
irritation eyes, skin, respiratory system; skin, resp sensitization; chest tightness, dyspnea (breathing difficulty), cough, dry throat, wheezing, pulmonary edema; 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: Quick drench
First Aid
(See procedures)
Eye: Irrigate immediately
Skin: Water flush immediately
Breathing: Respiratory support
Swallow: Medical attention immediately
Respirator Recommendations

NIOSH

Up to 0.1 ppm:
(APF = 10) Any supplied-air respirator*

Up to 0.25 ppm:
(APF = 25) Any supplied-air respirator operated in a continuous-flow mode*

Up to 0.5 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

See also: INTRODUCTION
 

Order NIOSH Publications

Contact Us:
USA.gov: The U.S. Government's Official Web PortalDepartment of Health and Human Services
Centers for Disease Control and Prevention   1600 Clifton Rd. Atlanta, GA 30333, USA
800-CDC-INFO (800-232-4636) TTY: (888) 232-6348, New Hours of Operation 8am-8pm ET/Monday-Friday
Closed Holidays - cdcinfo@cdc.gov