HMDI [Hydrogenated MDI]

HMDI [Hydrogenated MDI]

HMDI [Hydrogenated MDI] 

HMDI [Hydrogenated MDI] Characteristics
Synonyms Methylene bis(4-cyclo-hexylisocyanate), Dicyclohexylmethane 4,4'-diisocyanate
CAS No. 5124-30-1
Chemical formula CH2[(C6H10)NCO]2
Vapour density ---
Safe Work Australia ES TWA 2 ppb (based on 0.02 mg/m3 as NCO)
STEL 6 ppb (based on 0.07 mg/m3 as NCO)
Flammable limits LEL ---
UEL ---
Equipment group ---
Temperature classification ---
Chemical/physical properties One of the aliphatic diisocyanates, HMDI at room temperature is a clear, colourless to light-yellow liquid with low volatility.
Hazardous properties Like most diisocyanates, exposure to HMDI either by inhalation, ingestion or skin contact can lead to sensitisation(1). It is irritating to the skin (causing dermatitis) and eyes and can affect the respiratory system causing dyspnoea (breathing difficulty), pulmonary oedema and asthma.
Occurrence and uses Having high colour stability, HMDI is used as a curing agent for polyurethane foams.
Detectors available Colorimetric paper tape (0 – 100 ppb)
Suggested alarm levels 5 ppb
Notes (1)  Sensitisation is a phenomenon occurring in some individuals, whereby exposure to a substance leads to those individuals having an increased sensitivity to the effects of that substance.