Desmodur® diisocyanate

The polyamide copolymer of dodecanoic acid with methylenedi(cyclohexylamine) (MDCHA, PACM) was sold as continuous filament yam fiber under the tradename QIANA. As late as 1981, over 145,000 t was produced using high percentages, typically 80%, of trans, trans MDCHA isomer. The low melting raffinate coproduct left after t,t isomer separation by fractional crystallisation was phosgenated to produce a Hquid aUphatic diisocyanate marketed by Du Pont as Hylene W. Upon terrnination of their QIANA commitment, Du Pont sold the urethane intermediate product rights to Mobay, who now markets the 20% trans, trans—50% cis, trans—30% cis, cis diisocyanate isomer mixture as Desmodur W. In addition to its use in polyamides and as an isocyanate precursor, methylenedi (cyclohexyl amine) is used directiy as an epoxy curative. The Hquid diamine mixture identified historically as PACM-20 is marketed as AMICURE PACM by Anchor Chemical for performance epoxies. 

Methylenedi(cyclohexyhsocyanate) (45) [5124-30-1] (MDCHl, Desmodur W) is the dominant derivative of MDCHA and is used in light-stable urethanes. Polyurethane physical properties are dependent on the diamine geometric isomer composition used for the derivative diisocyanate which reacts with diol (87). 

Synonyms AI3-015101 BRN 0744602 CCRIS 3742 Desmodur T80 2,4-Diisocyanato-l-methylbenzene Diisocyanatoluene 2,4-Diisocyanotoluene Hylene T Hylene TCPA Hylene TLC Hylene TM Hylene TM-65 Hylene TRF Isocyanic acid, methylphenylene ester Isocyanic acid, 4-methyl-/ 3-phenylene ester 4-Methylphenylene diisocyanate 4-Methylphenylene isocyanate Mondur TD Mondur TD-80 Mondur TDS Nacconate 100 NCI-C50533 Niax TDI Niax TDI-P NSC 4791 NSC 56759 RCRA waste number U223 Rubinate TDI 80/20 TDI 2,4-TDI TDI-80 Toluene 2,4-diisocyanate Tolyene-2,4-diisocyanate Tolylene-2,4-diisocyanate 2,4-Tolylene diiso-cyanate /n-Tolylene diisocyanate UN 2078. 

HDI is the common name for hexamethylene diisocyanate. It is also known as 1,6-hexamethylene diisocyanate, 1,6-diisocyanatohexane, Mondur HX, and Desmodur H. It is a pale yellow liquid with a strong odor. HDI is found in hardening agents for automobile paints. 

Ferguson JS, Schaper M, Alarie Y. 1987. Pulmonary Effects of a Polyisocyanate Aerosol Hexamethylene Diisocyanate Trimer (HDlt) or Desmodur-N (DES-N). Toxicol Appl Pharmacol 89(3) 332-346. 

Fig. 15. Viscoelastic behavior of isocyanurate-oxazoiidone resins51). DEN 431 (polyglycidyl ether of phenol-formaldehyde novolac Dow Chemical Co.), EP 4080 (2,2-bis[p-(2,3-epoxypropyloxy)cyclo-hexane]propane Asahi Denka, Ltd.), EP 871 (diglycidyl ester of linoleic dimer acid Shell Chemical Co.), and L-MDI (modified diphenylmethane-4,4 -diisocyanate Desmodur CD Bater AG)...

The saturated analogue of MDI, 4,4 -dicy-clohexyl methane diisocyanate, has found limited use as an aiphatic isocyanate in adhesives. This material is known by a variety of names including Desmodur W (Bayer), hydrogenated MDI (or HMDI or Hl2MDI), reduced MDI (RMDI), and saturated MDI (SMDI), It is a low-viscosity liquid with a fairly high vapor pressure, so it too must be handled with care. In adhesive compositions, the diisocyanate usually is used to make an isocyanate functional prepolymer by reacting excess diisocyanate with a hydroxyl or amine functional polymer such as a polyester diol. 

Nonemulsifiable and emulsifiable polymeric methylene diisocyanates (Desmodur VP PU 1520 A 31 and 1520 E, Messrs. Bayer, West Germany) were combined with maize starch and solutions of tannin extract or protein. 

Blankenship [3] prepared polyethylene glycol carbamate, (II), as paint thickeners containing poIy(ethyIene oxide-b-propylene oxide-b-ethylene oxide) and either 1,6-hexamethyIene diisocyanate or 4,4 -methyIene bis-(isocyanatocy-clohexane). Polycarbamates were also prepared by Bauer [4] using a block polymer initiated by stearyl alcohol and consisting of poly(ethylene oxide-b-propylene oxide-b-butylene oxide-b-dodecene oxide-b-tetradecene oxide) coupled with the diisocyanate, Desmodur N . 

The industrial production of hexamethylenediamine became important with the discovery of the use of polyamides as synthetic fibres, the most important being Nylon-6,6. This polymer, prepared from adipic acid and hexamethylenediamine, was commercialized by DuPont in 1938 and it was virtually the only consumer of the entire production of this diamine until the development of light-stable polyurethanes. Those polymers, e.g. Desmodur N (Bayer) used in paints, are based on aliphatic diisocyanates prepared from the corresponding aliphatic diamine. 

PLURIISOCYANATE. Desmodur L75, provided by Bayer AG, is a 1,1,1-trimethylol propane/toluene diisocyanate adduct containing 25% ethyl acetate by weight. Density 1.17 g/ml NCO equivalent weight per kg 3.06 (by standard titration with di-n-butylamine). Desmodur L75 was used as received. Gel permeation chromatography has shown that this product contains in fact four species of different molecular weights and functionalities (9). 

SYNS DESMODUR H DESMODUR N HEXA-METHYLENDIISOKYANAT HEXAMETHYLENE DIISOCYANATE HEXAMETHYLENE DIISOCYANATE (DOT) HEXAMETHATENE-l, 6-DIISOCYANATE 1,6-HEXAMETHYLENE DIISOCYANATE 1,6-HEXANEDIOL DIISOCYANATE HMDI ISOCYANTC ACID, DIESTER with 1,6-HEXANEDIOL ISOCYANIC ACID, HEXAMETHYLENE ESTER METYLENO-BIS-FENYLOIZOCYJANIAN SZESCIOMETYLEN-ODWU IZOCYJANIAN TL 78... 

Desmophen 651A-65 and Desmophen R-221-75 at a solids weight ratio of 65/35 were used in this formulation. Desmodur N-3300 is a hexamethylene diisocyanate isocyanurate trimer (Bayer Material Science.)... 

Figure 3.39 Alicyclic isocyanates, (a) Isophorone diisocyanate (or 3-isocyanato-methyl-3,5,5—trimethylcyclohexyl isocyanate), Huels IPDI (b) l,4-bis(isocyanatometh-yl)cyclohexane, Mobay s p-Desmodur (c) l,3-bis(isocyanatomethyl)cyclohexane, Takeda s Hr,XDI (S3.50) (d) Methylene bis(4—cyclohexylisocyanate), Mobay s Desmodur W ( 3.00). also known as H12MDI, RMDI (reduced MD1), and PACM [bis-/ -aminocyclohcxyl methane].

Fuchs, S. Valade, P. Clinical and experimental study of several cases of intoxication by Desmodur T (toluene diisocyanate 1-2-4 and 1-2-6). Arch Mai Prof, 1951, 12 , 191-96. 

Benzene, 1,3 Jiisocyanatomethyl- CCRIS 596 Desmodur T 80 Desmodur T100 Diisocyanatotoluene 1,3-Diisocyanatomethylbenzene EINECS 247-722-4 HSDB 6003 Isocyanic acid, methyl-m-phenylene ester Methyl-m-phenylene isocyanate Methylphenylene isocyanate Mondur TD-80 Nacconate-lOO Niax iso-cyanate TDI RCRA waste number U223 Rubinale TDI Rubinate TDI 80/20 TDI TDI 80-20 Toluene-2,4-diisocyanate (mixt. with Toluene-2,6-diisocyanate) Toluene diisocyanate 2,4/2,6-Toluene diisocyanate iso-meric mixture 2,4-Toluene diisooyanate 2,4- and 2,6-Toluene diisocyanate Toluenediisocyanate (mixed isomers) Tolylene diisocyanate Tolylene isocyanate m-Tolylidene diisocyanate UN 2078. Mixture of... 

Polyurethane bulk and thin-film samples are prepared from a two-part PU adhesive formed by polyaddition of Bayer Desmodur CD (89% diphenylmethane-4,4 -diisocyanate 1 with 11% uretoneimine triisocyanate 2 as additive) with a polyol mixture of Bayer Desmophen 2060BD (linear poly(propylene ether) diol... 

Desmodur VK-10 Bayer 66 Mixture of 4,4 -diphenylmethane diisocyanate (MDl) isomers and higher homologues (PMDl)... 

Azthane 1-100 Desmodur I isophorone diisocyanate Tetramethoxymethyi giycoiurii... 

Desmocoii 420, Desmocoii 500. See Polyurethane, thermoplastic Desmodur 44 M L Fiakes, Desmodur 44 MC L Liq., Desmodur 2460 M. See MDI Desmodur BL 1100. See Polyurethane resin Desmodur CD. See MDI Desmodur i. See Isophorone diisocyanate Desmodur MP-225. See MDI Desmodur VK-5, Desmodur VK-18, Desmodur VK-70, Desmodur VK-200, Desmodur VKS-2, Desmodur VKS-4, Desmodur VKS-5, Desmodur VKS-18. See Polymethylene polyphenyl isocyanate Desmoiac 2100. See Polyurethane resin Desmopan 150, Desmopan 155, Desmopan 356, Desmopan 359, Desmopan 385, Desmopan 392, Desmopan 445,... 

Baymidur KL 3-5001 Desmodur I Isophorone diisocyanate Luxate IM Vestanat IPDI 4109-96-0 Dichlorosilane SID3368.0 4112-89-4... 

To the tannin/hexamine solution were added the modified GA, GB and GC lignin solutions. The proportion of tannin modified lignin was 50 50 by weight as shown in Table 1. The pMDI (polymeric 4,4 -diphenylmethane diisocyanate) used was Desmodur 44VK from Bayer. The PF resin used in one of the formulations in Table 1 was prepared according to the procedure already presented [20]. 

Dicyclohexamethane 4,4 diisocyanate or bis (4-isocyanate cyclohexyl) methane (Hydrogenated MDI, HMDI), Desmodur W 132 31.8 ... 

The most important polyurethane adhesive components are toluene diisocyanate (TDI), 4,4 -diphenylmethane diisocyanate (MDI), p-anisidine diisocyanate (DADI), hexamethylene diisocyanate (HDI) and triphenyl-methane triisocyanate (Desmodur R) (see Fig. 8.1), together with various polyester and polyether glycols. (See Fig. 1.9 of Chapter 1 for the formulae of TDI, MDI and HDI, and Fig. 8.5 for the formula of DADI.) Toluidine diisocyanate (TODI) (Fig. 8.1) is also used. 

Elastomer coatings may be adhered to synthetic fibre fabrics and other materials by diisocyanates which are applied directly to the fabric, usually as a solution (typically of 2% concentration) in toluene or methylene chloride or some similar non-reactive solvent, by dipping, spraying, roller coating and then drying. After this process the elastomer coating is applied to the treated fabric. Typical diisocyanates used for this purpose are MDI and 4,4, 4"-triphenylmethane triisocyanate (Desmodur R). 

In this, one part consists of a polyester or polyether dissolved in an inert solvent and this is mixed with its molar equivalent of a diisocyanate dissolved in solvent. Usually ethyl acetate is the solvent and typical solution concentrations are 70% total solids. A suitable diisocyanate would be Desmodur HH (see Fig. 8.6) in ethyl acetate at 75% solids content. At room temperature such a cement has a pot life of 1-2 days and with accelerator, only 3 h. The setting time of this cement, containing accelerators, in wood adhesion, is 4-5 h at 10°C, 7h at O C, overnight at less than 0°C. 

Fig. 8.6. Isocyanate for a two-part adhesive system (Desmodur HH, an adduct from 1,6-hexamethylene diisocyanate (3mol) and 3-methylolpentylene...

Polycaprolactone diol MW = 2000 4,4-methylene bis cyclohexyl diisocyanate (Desmodur W)... 

Aliphatic diisocyanates can have strong, adverse skin irritation effects and two are well known for this problem, namely dicyclohexylmethane diisocyanate (H12MDI) (Desmodur W by Bayer) and hexamethylene diisocyanate (HDI). Usually care in handling and good hygiene prevents undue problems. Occasionally a more serious effect has been observed in one instance a chemical worker exposed her face to the hot vapour of dicyclohexylmethane diisocyanate and within 24 h her head had swollen to 20% of its original size and characteristic red spots with a white centre were present over the exposed area. Recovery took place slowly over a period of 3 weeks with cortisone-type ointment treatments. Her central nervous system was also affected and took some months to become normal. This was a very unusual and unique incident and is recorded to show that occasionally the unexpected human response can occur with diisocyanates. 

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