Toluene diisocyanate for

Micronuclei were not induced in erythrocytes of mice or rats exposed to atmospheric concentrations of 1.1 mg/m toluene diisocyanate for 6 h per day on five days per week for four weeks. 

Uses Aviation gasoline additive octane booster in gasoline solvent for paints, gums, resins, rubber, inks, cleaners, adhesives, cosmetics, pharmaceuticals diluent, thinner in nitrocellulose lacquers thinner for perfumes, dyes alcohol denaturant process solvent adhesive solvent in plastic toys in extraction of various principles from plants mfg. of benzene, benzoic acid, benzaldehyde, toluene diisocyanate for PU resins, dyes, TNT for explosives, toluene sulfonates for detergents and dyestuffs adjuvant in resinous/polymeric food-contact coatings in paper/paperboard in contact with dry food in acrylic food pkg. in cellophane for food pkg. adjuvant for PC food-pkg. resins solvent in food-contact PPO resins in food-pkg. adhesives Regulatory FDA 21CFR 175.105, 175.320, 176.180, 177.1010, 177.1200, 177.1440,... 

Toluene 2,4-diamine CH, Manufacture of toluene diisocyanate (for elastomers), dyes, resins, fungicides VOC... 

About 7% of toluene production is used as a feedstock to produce toluene diisocyanate for use in polyurethane technology. 

Phosgene (for toluene diisocyanate, dipbenylmetbane diisocyanate, and polycarbonate resin manufacture), cbloroisocyanuric acid, cyanuric cbloride. 

These foams are produced from long-chain, Hghtiy branched polyols reacting with a diisocyanate, usuaUy toluene diisocyanate [1321 -38-6] (TDI), to form an open-ceUed stmcture with free air dow during dexure. During manufacture these foams are closely controUed for proper density, ranging from 13 to 80 kg/m (0.8—5 lbs/ft ), to achieve the desired physical properties and cost. 

For methylene diphenyl diisocyanate (MDI), the initial reaction involves the condensation of aniline [62-53-3] (21) with formaldehyde [50-00-0] to yield a mixture of oligomeric amines (22, where n = 1, 2, 3...). For toluene diisocyanate, amine monomers are prepared by the nitration (qv) of toluene [108-88-3] and subsequent hydrogenation (see Amines byreduction). These materials are converted to the isocyanate, in the majority of the commercial aromatic isocyanate phosgenation processes, using a two-step approach. 

A convenient method for the synthesis of these low boiling materials consists of the reaction of /V,/V-dimethy1iirea [96-31-1] with toluene diisocyanate to yield an aUphatic—aromatic urea (84). Alternatively, an appropriate aUphatic—aromatic urea can be prepared by the reaction of diphenylcarbamoyl chloride [83-01-2] with methylamine. Thermolysis of either of the mixed ureas produces methyl isocyanate ia high yield (3,85). 

Yield for the process at low catalyst loading is 95%. AJ-Methyl-toluenediamiae, one of the reaction by-products, represents not only a reduction ia yield, but also a highly objectionable impurity ia the manufacture of toluene diisocyanate. Low concentrations of CO (0.3—6% volume) control this side reaction. 

Toluene Diisocyanate. Toluene diisocyanate is the basic raw material for production of flexible polyurethane foams. It is produced by the reaction sequence shown below, in which toluene is dinitrated, the dinitrotoluene is hydrogenated to yield 2,4-diaminotoluene, and this diamine in turn is treated with phosgene to yield toluene 2,4-diisocyanate. 

An equimolar mixture of carbon monoxide and chlorine reacts at 500 K under a slight positive pressure. The reaction is extremely exothermic (Ai/gQQp. = —109.7 kJ or —26.22 kcal), and heat removal is the limiting factor in reactor design. Phosgene (qv) is often produced on-site for use in the manufacture of toluene diisocyanate (see Amines, aromatic-diaminotoluenes Isocyanates, organic). 

The dinitrotoluenes are important precursors for toluene diisocyanates (TDI), monomers used to produce polyurethanes. 

No by-product is formed from this reaction. Toluene diisocyanate (Chapter 10) is a widely used monomer. Diols and triols produced from the reaction of glycerol and ethylene oxide or propylene oxide are suitable for producing polyurethanes. 

PUR are a broad class of highly cross-linked plastics prepared by multiple additions of poly-functional hydroxyl or amino compounds. Typical reactants are polyisocyanates [toluene diisocyanate (TDI)] and polyhydroxyl molecules such as polyols, glycols, polyesters, and polyethers. The cyanate group can also combine with water this reaction is the basis for hardening of the one-part foam formulations. 

Up to this point we have discussed only carbamates la-4a with a single carbamate group on the phenyl ring as model systems for aromatic polyurethane photodecomposition. In polyurethane coatings based on the aromatic diisocyanate TDI two carbamate groups are attached to the phenyl ring. Furthermore commercially available TDI is actually a mixture of 2,4-toluene diisocyanate (2,4-TDI) and 2,6-toluene diisocyanate (2,6-TDI) which when formulated give 2,4- and 2,6-biscarbamates. Model systems for these species would then be biscarbamates of 2,4-TDI and 2,6-TDI (as shown below) and not carbamates such as la-4a. 

Matheson, J.M., Johnson, V.J., and Luster, M.I., Immune mediators in a murine model for occupational asthma studies with toluene diisocyanate, Toxicol. Sci., 84, 99, 2005. 

Certain LMW agents will cause OA via a poorly defined mechanism. Only about 20% of workers with OA to toluene diisocyanate (TDI) have IgE detectable to TDI indicating that IgE antibody may be more an indicator of exposure rather than a mediator of the disease [10], Similar data exist for workers with asthma caused by plicatic acid from western red cedar [11], The inability to detect IgE antibody in the majority of these workers may be based in technical issues such as the nature of the chemical-protein... 

Depending on starting diamines these are three toluene diisocyanates, i.e > 80,20 65,35 or 100 per cent 2, 4 toluene diisocyanate. All these are commercially available. They are respiratory irritants and should be handled carefully 80,20 toluene diisocyanate is used widely for production of flexible foams. 

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