Tetramethylxylylene diisocyanate

HMD was originally produced by Du Pont as a coproduct in the manufacture of Qiana fiber. Du Pont subsequently sold the product to Bayer. In the 1990s MDA is hydrogenated by Air Products for Bayer (see Amines, aromatic-methylenedianiline). Commercial HMDI is a mixture of three stereoisomers. Semicommercial aUphatic diisocyanates include /n j -cyclohexane-l,4-diisocyanate (CHDI) and y -tetramethylxylylene diisocyanate (TMXDI). A coproduct in the production of TMXDI is y -isopropenyl-a,a-dimethylben2yl isocyanate (TMI), which can be copolymerized with other olefins to give aUphatic polyisocyanates. 

More recently, other nonphosgene routes for the preparation of aliphatic isocyanates have been reported. For example, American Cyanamid has disclosed the reaction of diisopropenylbenzene with HC1 and isocyanic acid [75-13-8] to yield tetramethylxylylene diisocyanates (57). 

Hexamethylene diisocyanate 2.2.4- Trimethylhexamethylene diisocyanate Hydrogenated xylylene diisocyanate 1.4- Cyclohexane diisocyanate 4,4 -Dicyclohexylmethane diisocyanate Xylylene diisocyanate Tetramethylxylylene diisocyanate Tolulene diisocyanate Diphenylmethane diisocyanate Poly(ethylene glycol) Poly(propylene glycol) Poly(tetramethylene ether glycol) Poly(hexamethylene ether glycol) Poly(ethylene adipate) Poly(butylene adipate) Poly(neopentyl adipate) Poly(3-methylpentyl adipate) Poly(caprolactone) diol... 

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