2.2.4- Trimethylhexamethylene diisocyanate

The common aliphatic diisocyanates are hexamethylene diisocyanate, hydrogenated (H12) 4,4 -dipenylmethane diisocyanate, isophorone diisocyanate, 2,2,4-trimethylhexamethylene diisocyanate, and 2,4,4-trimethylhexamethylene diisocyanate. Other aliphatic diisocyanates in various stages of commercialization are lysine diisocyanate, methylcyclohexyl diisocyanate, isopropylidine bis-(4-cyclohexyl isocyanate), and tetramethylene diisocyanate. Many additional polyfunctional isocyanates are described in the literature. 

The SH- and NCO-terminated linear thiourethane telechelics containing units (114) (Mn = 520-610) were synthesized hy DABCO-catalyzed addition reaction of 3,6-dioxaoctane-l,8-dithiol [14970-87-7] with various diisocyanates, including HDI, the mixture of 2,4,4-trimethylhexamethylene diisocyanate [15646-96-5] and 2,2,4-trimethylhexamethylene diisocyanate [6938-22-0], and isophorone diisocyanate [4098-71-9]. It has been shown that NCO-terminated prepol5uners can he transformed into telechelics with olefinic end groups by treating with allyl alcohol [107-18-6], 2-hydroxyethyl methacrylate, or diallylamine [124-02-7] (288). 

Trimethylhexamethylene diisocyanate (TMDi) FIGURE 8.1 Diisocyanates in biodegradable polyurethanes (PUs). 

Trimethylhexamethylene diisocyanate (TMDI), 14 588 Trimethyl isocyanurate, 8 205 Trimethylolethane, 2 47 economic aspects, 2 52 physical properties of, 2 48t... 

Addition product of 2 mol 2-hydix>xylethyl methacrylate and 1 mol 2,2,4-trimethylhexamethylene diisocyanate. 

Poly(urethane) resins have been proposed as dispersant resins. Possible components for such resins are shovm in Table 3.38. 2,2,4-Trimethylhexamethylene diisocyanate and other compoimds are shown in Figure 3.42. 

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... 

Hexamethyiene diisocyanate 1,4-Cyciohexane diisocyanate Figure 3.42 2,2,4-Trimethylhexamethylene diisocyanate. 

Diphenylmethane diisocyanate (MDI) 1,5-Naphthalene diisocyanate (NDI) Hexamethylene diisocyanate (HDI) Polymethylene polyphenyl isocyanate (PMPI) Isophorone diisocyanate (IPDI) Trimethylhexamethylene diisocyanate (TMDI)... 

The most commonly used difunctional isocyanates are TDI, MDI and 1,6-hexamethylene diisocyanate or 1,6-diisocyanatohexane (HDI). TDI often contains mixtures of the isomers 2,4-TDI and 2,6-TDI. MDI is industrially used as a mixture of 4,4 -MDI with 2,4 -MDI and 2,2 -MD which is also called polymethylene polyphenyl isocyanate (PAPI or PMPPI). Phenyl isocyanate is usually a trace constituent in commercial MDI products. Examples of other diisocyanates include isophorone diisocyanate (IPDI), trimethylhexamethylene diisocyanate (TMDI), naphthalene diisocyanate (NDI), triphenyl-methane triisocyanate (TPMTI), and DMDI (Malten 1977> 1982, i984a,b, i987a,b Bjorkner 1992 Elvers et al. 1991 Estlander et al. 1992 Karol and Kramarik 1996). 

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