ISOPHORONE DIISOCYANATE

CAS Number: 4098-71-9
Chemical formula: C12H18N2O2
Molar mass: 222.3 g/mol

Isophorone diisocyanate (IPDI) is an organic compound in the class known as isocyanates. More specifically, it is an aliphatic diisocyanate.
It is produced in relatively small quantities, accounting for (with hexamethylene diisocyanate) only 3.4% of the global diisocyanate market in the year 2000.
Aliphatic diisocyanates are used, not in the production of polyurethane foam, but in special applications, such as enamel coatings which are resistant to abrasion and degradation from ultraviolet light.
These properties are particularly desirable in, for instance, the exterior paint applied to aircraft.

IPDI exists in two stereoisomers, cis and trans.
Their reactivities are similar.
Each stereoisomer is an unsymmetrical molecule, and thus has isocyanate groups with different reactivities.
The primary isocyanate group is more reactive than the secondary isocyanate group.

Isophorone Diisocyanate (IPDI) is an organic compound with a chemical structure C12H18N2O2.
Isophorone Diisocyanate is a colorless liquid or slightly yellowish, with a pungent odor. It is insoluble in water on contact with which it decomposes, but miscible with many organic solvents (hydrocarbons, esters, ketones, …)

Production
IPDI is obtained by phosgenation of isophorone diamine during a five steps reaction:
Condensation:Isophorone is obtained from acetone with a catalyst
Hydrocyanation:Isophorone react with hydrogen cyanide to form isophorone nitrile
Reductive amination:isophorone nitrile react the with ammonia, hydrogen and a catalyst, to form a mixture of isophorone diamine conformers with a ratio 25/75 cis/trans
Phosgenation:Isophorone diamine react with phosgene to form a crude mixture containing IPDI conformers (25/75 cis/trans)
Purification:Distillation of the crude IPDI to extract pure IPDI
IPDI exists in two conformers, cis and trans. Their reactivities are similar. Each conformer is an asymmetrical molecule, and thus has isocyanate groups with different reactivities. The secondary isocyanate group is more reactive than the primary isocyanate group.

Uses
IPDI is  used in the production of special applications, such as:
Polyurethanes resins (PUR), Resins for coatings & inks, elastomers & TPU, leather & textile
Aqueous dispersible polyurethane polymers (PUD) showing exceptional weathering resistance.
Preparation of light-stable polyurethanes. It is involved in particular in the manufacture of paints, varnishes and elastomers
Enamel coatings which are resistant to abrasion and degradation from ultraviolet light. IPDI bring hardness to the coating.
Polyurethane manufacturing with high stability, resistance to discoloration of light and chemical resistance;
Treatment of paints and varnishes to give them properties of hardness, flexibility, chemical resistance, impact and weather resistance;
Elastomer used in sealants and highly flexible textile coatings;
Hard industrial foams and coatings,
Contact lens manufacturing
IPDI is not used in the production of polyurethane foam
Arpadis is one of the largest chemical distributor in Europe.
Arpadis is handling the storage, transport, export & import formalities of Isophorone Diisocyanate (IPDI) globally.

IPDI (isophorone diisocyanate) is a cycloaliphatic diisocyanate and characterized by its two reactive isocyanate groups comprising differences in reactivity (primary and secondary NCO groups). This leads to a high selectivity in the reaction with hydroxyl groups bearing compounds. This unique property is advantageous for the processing of low viscosity prepolymers leading to a comparably low content of residual, monomeric diisocyanate at the same time. By choice of an appropriate catalyst (i.e. dibutyl tin dilaurate, DBTDL), the rate of conversion is increased, but also the degree of selectivity is further enhanced. The low viscosity of IPDI-based prepolymers allows for the reduction of solvents (VOC). The methyl groups attached to the cyclohexane ring make VESTANAT® IPDI and the corresponding derivatives widely compatible with resins and solvents.Low viscosity liquid for the synthesis of light stable polyurethanes. Due to differently reactive isocyanate groups especially suitable for the selective reaction with polyols to PUR prepolymers with very narrow molecular weight distribution, low viscosity and low monomer content.

The cycloaliphatic ring itself gives products based on VESTANAT® IPDI more rigidity and a high glass transition temperature. VESTANAT® IPDI is a colorless, low viscosity liquid with a solidification point of – 60°C. Semi-finished products, e.g. NCO terminated prepolymers have low tendencies to crystallize but rather stay liquid and are easy processable. As a cycloaliphatic diisocyanate, VESTANAT® IPDI meets all requirements for the manufacture of light stable and weatherable polyurethanes also comprising excellent mechanical properties and chemical resistance.

Benefits
Differently reactive isocyanate groups
High selectivity
Low viscosity of prepolymers
Low residual monomer content in prepolymers
High glass-transition temperature
Low tendency for crystallization
High NCO content
Highest toughness and flexibility at low temperature

Density: 1.062 g/cm3 @ 20 °C, liquid
Melting Point: −60 °C
Boiling Point: 158 °C (316 °F; 431 K) at 1.33 kPa
Odor: Pungent
Color/Form: Colorless to slightly yellow liquid
XLogP3-AA: 4.5
Hydrogen Bond Donor Count    : 0
Hydrogen Bond Acceptor Count: 4
Rotatable Bond Count: 3
Exact Mass: 222.136827821
Monoisotopic Mass: 222.136827821
Topological Polar Surface Area: 58.9 Ų
Heavy Atom Count: 16
Formal Charge: 0
Complexity: 352
Isotope Atom Count: 0
Defined Atom Stereocenter Count: 0
Undefined Atom Stereocenter Count: 2
Defined Bond Stereocenter Count: 0
Undefined Bond Stereocenter Count: 0
Covalently-Bonded Unit Count: 1
Compound Is Canonicalized    : Yes

Isophorone diisocyanate is also known as:
Cyclohexane, 5-isocyanato-1-(isocyanatomethyl)-1,3,3-trimethyl-;
3-Isocyanatomethyl-3,5,5-trimethyl cyclohexylisocyanate;
Isophorone diamine diisocyanate;
Triisocyanatoisocyanurate;
Monomeric cycloaliphatic diisocyanate
Cyclohexane, 5-isocyanato-1-(isocyanatomethyl)-1,3,3-trimethyl-;
IPDI
IPDI is produced in relatively small quantities. With hexamethylene diisocyanate HDI, IPDI accounting only for approximately 5% of the global diisocyanate market. 

Isophorone Diisocyanate (IPDI) by Vencorex is used in the chemical synthesis of aliphatic polyisocyanates and polyurethanes, such as aqueous dispersible polyurethane polymers (PUD) showing exceptional weathering resistance. Improves hardness due to its rigid cycloaliphatic structure. It has a shelf life of 12 months.

Kinetic studies of the catalyzed urethane reactions between isophorone diisocyanate (IPDI) and alcohols and of the urea reactions between an isocyanate-terminated prepolymer [IPDI–PPG2000–IPDI, where PPG2000 is poly(propylene glycol) with a number-average molecular weight of 2000 g/mol] and water in the bulk state were performed with Fourier transform infrared (FTIR) spectroscopy. Dibutyltin dilaurate was used as the catalyst for the urethane reaction, and various tertiary amines were used as catalysts for the urea reactions. The reactions were followed through the monitoring of the change in the intensity of the absorbance band for NCO stretching at 2270 cm−1 in the FTIR spectra; the activation parameters were determined through the evaluation of the kinetic data obtained at various temperatures (within the range of 30–60°C). The kinetic data indicated that the catalyzed isocyanate/alcohol and isocyanate/water reactions both followed second-order kinetics during their initial stages but later followed third-order kinetics resulting from the autocatalytic effects of hydrogen bonding between the hydroxyl groups and the newly formed urethane and urea groups. Furthermore, activation energies of 64.88 and about 80 kJ/mol for the isocyanate/alcohol and isocyanate/water reactions, respectively, indicated that the urea-forming reactions were more sensitive to the reaction temperature than the urethane-forming reactions.

Isophorone diisocyanate (IPDI) trimer based novel polyurea core shell structures were developed by interfacial polymerization. Different operating conditions have been used to fabricate shell to encapsulate core. Characterizations of prepared microcapsules were done by Fourier transform infrared spectroscopy, thermogravimetric analysis, and particle size analyzer. The surface morphology of microcapsules was examined by optical microscopy, scanning electron microscopy, and transmission electron microscopy. The release rate of core from microcapsules was estimated by UV and gas chromatography. The results revealed that tailor made release can be adjusted by varying operational protocol for shell and fabricated shell can be extended to other applications such as self-healing coatings and drug delivery.

Isophorone diisocyanate, also known as IPDI, is a chemical compound of cyanide and an aliphatic diisocyanate. Aliphatic diisocyanates are used in special applications, such as enamel coatings which are resistant to abrasion and degradation from ultraviolet light. These properties are particularly desirable in, for instance, the exterior paint applied to aircraft. 

Diisocyanates (or polyisocyanates) are monomers for polyurethane production.
Polyurethane is made from a variety of diisocyanates in conjunction with polyether and polyester polyols as co-reactants by addition polymerization which needs at least two -N=C=O groups.
Polyurethanes are widely used in the manufacture of flexible and rigid foams, fibres, coatings, and elastomers. 

Cyanuric acid (also called pyrolithic acid), white monoclinic crystal with the structure of [HOC(NCOH)2N], is the compound of polymerized cyanic acid.
Cyanic acid hydrolyses to ammonia and carbon dioxide in water.
Its salts and esters are cyanates (or called fulminates). Esters of normal cyanic acid are not known.
There is another isomeric cyanic acid with the structure of H-N=C=O, which is called isocyanic acid.
Its salts and esters are isocyanates.
Cyanates (or Isocyanates) are used in the manufacturing pharmaceuticals, pesticides, textile softener, lubricants and industrial disinfectants through the conversion to polycyclic compounds (such as hydantoins and imidazolons) They are used as plastic additives and as heat treatment salt formulations for metals.

Synthesis
There are five steps to the synthesis of pure IPDI:
Condensation: Conversion of acetone with a catalyst to produce isophorone

Hydrocyanation: Reaction of the isophorone with hydrogen cyanide to form isophorone nitrile

Reductive amination: Reaction of the isophorone nitrile with ammonia, hydrogen and a catalyst, to form a mixture of isophorone diamine conformers (25/75 cis/trans)

Phosgenation: Reaction of the isophorone diamine with phosgene to form a crude mixture containing IPDI conformers (25/75 cis/trans)
Purification: Distillation of the crude IPDI to extract pure IPDI

Isophorone diisocyanate exists in two stereoisomers, cis and trans.
Their reactivities are similar.
Each stereoisomer is an unsymmetrical molecule, and thus has isocyanate groups with different reactivities.
The primary isocyanate group is more reactive than the secondary isocyanate grou

IPDI is a colourless, volatile, poisonous inorganic compound with the formula HNCO; the simplest stable chemical compound that contains carbon, hydrogen, nitrogen, and oxygen, the four most commonly-found elements in organic chemistry and biology.
It is a hydracid and a one-carbon compound.
It is a conjugate acid of a cyanate. It is a tautomer of a cyanic acid.

Although the electronic structure according to valence bond theory can be written as HN=C=O, the vibrational spectrum has a band at 2268.8 cm−1 in the gas phase, which clearly indicates a carbon–nitrogen triple bond.
Thus the canonical form H+N≡C−O− is the major resonance structure.

Isophorone diisocyanate, has emerged as a potentially important reduced nitrogen compound that is emitted in wildfires, and may have health effect implications.
The extent of the health effects depends on the solubility of HNCO in aqueous and non-aqueous solutions and the relative rates of hydrolysis versus carbamylation reactions (for example: HNCO+ROH => H2NC(O)OR).
We report here results of studies of HNCO solubility and its reaction in buffered aqueous solutions (pH3), tridecane, and n-octanol at temperatures over the range 5 to 37°C.
From these data, the heats of solution and activation energy of hydrolysis are estimated, and a partition coefficient between n-octanol and water at 25°C is greater than 1 for low pH solutions, indicating appreciable portioning to a non-polar phase, but HNCO will be distributed mostly in the aqueous phase at neutral pH.
In addition, it was found that the rate of reaction of HNCO with n-octanol was competitive with hydrolysis under physiologically relevant conditions (pH7.4, 37°C), indicating that carbamylation of ROH groups could be significant.
Based on these results, research on the carbamylation of other functional groups, and solubility and reaction studies of other isocyanates (e.g. CH3NCO) are warranted.
The implications of this multi-phase chemistry for global exposures to wildfire emissions will be discussed.

Isophorone diisocyanate is a well-known air pollutant that affects human health.
Biomass burning, smoking, and combustion engines are known HNCO sources, but recent studies suggest that secondary production in the atmosphere may also occur.
We directly observed photochemical production of HNCO from the oxidative aging of diesel exhaust during the Diesel Exhaust Fuel and Control experiments at Colorado State University using acetate ionization time-of-flight mass spectrometry.
Emission ratios of HNCO were enhanced, after 1.5 days of simulated atmospheric aging, from 50 to 230 mg HNCO/kg fuel at idle engine operating conditions.
Engines operated at higher loads resulted in less primary and secondary HNCO formation, with emission ratios increasing from 20 to 40 mg HNCO/kg fuel under 50% load engine operating conditions. These results suggest that photochemical sources of HNCO could be more significant than primary sources in urban areas.

Isophorone diisocyanate, an acidic gas found in tobacco smoke, urban environments and biomass burning-affected regions, has been linked to adverse health outcomes.
Gasoline- and diesel-powered engines and biomass burning are known to emit HNCO and hypothesized to emit precursors such as amides that can photochemically react to produce HNCO in the atmosphere.
Increasingly, diesel engines in developed countries like the United States are required to use Selective Catalytic Reduction (SCR) systems to reduce tailpipe emissions of oxides of nitrogen.
SCR chemistry is known to produce HNCO as an intermediate product, and SCR systems have been implicated as an atmospheric source of HNCO.
In this work, we measure HNCO emissions from an SCR system-equipped diesel engine and, in combination with earlier data, use a three-dimensional chemical transport model (CTM) to simulate the ambient concentrations and source/pathway contributions to HNCO in an urban environment.
Engine tests were conducted at three different engine loads, using two different fuels and at multiple operating points. HNCO was measured using an acetate chemical ionization mass spectrometer.
The diesel engine was found to emit primary HNCO (3-90 mg kg-fuel-1) but we did not find any evidence that the SCR system or other aftertreatment devices (i.e., oxidation catalyst and particle filter) produced or enhanced HNCO emissions.
The CTM predictions compared well with the only available observational data sets for HNCO in urban areas but under-predicted the contribution from secondary processes.
The comparison implied that diesel-powered engines were the largest source of HNCO in urban areas. The CTM also predicted that daily-averaged concentrations of HNCO reached a maximum of 110 pptv but were an order of magnitude lower than the 1 ppbv level that could be associated with physiological effects in humans.
Precursor contributions from other combustion sources (gasoline and biomass burning) and wintertime conditions

Isophorone diisocyanate, an acidic gas found in tobacco smoke, urban environments, and biomass-burning-affected regions, has been linked to adverse health outcomes.
Gasoline- and diesel-powered engines and biomass burning are known to emit HNCO and hypothesized to emit precursors such as amides that can photochemically react to produce HNCO in the atmosphere.
Increasingly, diesel engines in developed countries like the United States are required to use selective catalytic reduction (SCR) systems to reduce tailpipe emissions of oxides of nitrogen.
SCR chemistry is known to produce HNCO as an intermediate product, and SCR systems have been implicated as an atmospheric source of HNCO.
In this work, we measure HNCO emissions from an SCR system-equipped diesel engine and, in combination with earlier data, use a three-dimensional chemical transport model (CTM) to simulate the ambient concentrations and source/pathway contributions to HNCO in an urban environment.
Engine tests were conducted at three different engine loads, using two different fuels and at multiple operating points. HNCO was measured using an acetate chemical ionization mass spectrometer.
The diesel engine was found to emit primary HNCO (3-90 mg kg fuel-1) but we did not find any evidence that the SCR system or other aftertreatment devices (i.e., oxidation catalyst and particle filter) produced or enhanced HNCO emissions.
The CTM predictions compared well with the only available observational datasets for HNCO in urban areas but underpredicted the contribution from secondary processes. The comparison implied that diesel-powered engines were the largest source of HNCO in urban areas.
The CTM also predicted that daily-averaged concentrations of HNCO reached a maximum of ˜ 110 pptv but were an order of magnitude lower than the 1 ppbv level that could be associated with physiological effects in humans.
Precursor contributions from other combustion sources (gasoline and biomass burning) and wintertime

4098-71-9
IPDI
5-Isocyanato-1-(isocyanatomethyl)-1,3,3-trimethylcyclohexane
Isophorone diamine diisocyanate
Cyclohexane, 5-isocyanato-1-(isocyanatomethyl)-1,3,3-trimethyl-
3-Isocyanatomethyl-3,5,5-trimethylcyclohexyl isocyanate
3-Isocyanatomethyl-3,5,5-trimethylcyclohexylisocyanate
CHEBI:53214
Isocyanic acid, methylene(3,5,5-trimethyl-3,1-cyclohexylene) ester
MFCD00064956
UNII-43B0856528
Isophorone diisocyanate, 98%
Isophorone Diisocyanate (mixture of isomers)
DSSTox_CID_3826
DSSTox_RID_77200
DSSTox_GSID_23826
43B0856528
CAS-4098-71-9
CCRIS 6252
HSDB 6337
EINECS 223-861-6
UN2290
BRN 2726467
Vestanat IPDI
Isophorone diisocyanate [Diisocyanates]
ACMC-209u7p
Epitope ID:113238
EC 223-861-6
SCHEMBL15846
CHEMBL1509442
DTXSID0023826
1-isocyanato-3-isocyanatomethyl-3,5,5-trimethylcyclohexane
5-isocyanato-1-(isocyanatomethyl)-1,3,3-trimethyl-cyclohexane
Tox21_201520
Tox21_300298
ANW-43427
AKOS000120330
Cyclohexane, 5-isocyanato-1-(isocyanatomethyl)-1,3,3-trimethyl-, homopolymer
MCULE-9344603023
UN 2290
NCGC00091745-01
NCGC00091745-02
NCGC00091745-03
NCGC00091745-04
NCGC00254143-01
NCGC00259070-01
I0314
ST50825731
Isophorone diisocyanate [UN2290] [Poison]
A825377
Q415415
methylene(3,5,5-trimethyl-3,1-cyclohexylene) ester
1,1,5,5-Tetramethylcyclohexane-.alpha.',3-diisocyanate
3-(isocyanatomethyl)-3,5,5-trimethylcyclohexanisocyanate
F2191-0302
1-isocyanato-3,3,5-trimethyl-5-isocyanatomethylcyclohexane
3,3,5-Trimethyl-5-(isocyanatomethyl)cyclohexyl isocyanate
3-(Isocyanatomethyl)-3,5,5-trimethylcyclohexyl isocyanate
5-isocyanato-1-isocyanatomethyl-1,3,3-trimethylcyclohexane
1,3,3-Trimethyl-1-(isocyanatomethyl)-5-isocyanatocyclohexane
1-(Isocyanatomethyl)-5-isocyanato-1,3,3-trimethylcyclohexane
1-iso cyanato-3,3,5-trimethyl-5-isocyanatomethyl cyclohexane
1-Isocyanato-3,3,5-trimethyl-5-(isocyanatomethyl)cyclohexane
1-isocyanato-3,3,5-trimethyl-5-isocyanato methyl cyclohexane
1-isocyanato-3,3,5-trimethyl-5-isocyanatomethyl cyclohexane
1-Isocyanato-3-(isocyanatomethyl)-3,5,5-trimethylcyclohexane
1-isocyanato-3-isocyanatomethyl-3,5,5-trimethyl cyclohexane
1-Isocyanato-5-(isocyanatomethyl)-3,3,5-trimethylcyclohexane
3-Isocyanatomethyl-3,5,5-trimethylcyclohexyl isocyanate homopolymer
Isocyanic acid, diester with 5-hydroxy-1,3,3-trimethylcyclohexanemethanol