A -Methyldiethanolamine

Alkanolamines are used during the sweetening process in the oil and gas industry to remove toxic levels of gases such as hydrogen sulfide and carbon disulfide from raw gas condensates. Various alkanolamines such as A-methyldiethanolamine (23) and triethanolamine (25) may be utilized. They are therefore of concern as environmental contaminants of groundwater and wetland areas. Headley et al. (66)... 

Nitrogen mustards are hydrolyzed to the corresponding ethanolamines (12a-c) in aqueous media and, like TDG, these are expected to be excretion products following exposure. No detailed mass spectrometric studies of the in vivo metabolism of nitrogen mustards have been reported. Lemire et al. (32) referred to unpublished studies that showed substantial amounts of free (unconjugated) A-ethyl and A-methyldiethanolamine were present in 24 h and 48 h urine from rats exposed to HN-1 and HN-2 respectively. In vitro studies have indicated that A-demethylation may be an important metabolic pathway for HN-2 (33). 

Oil-in-water microemulsions were prepared using butyl acrylate as the monomer, sodium dodecylsulfate as surfactant, and 1-pentanol as co-surfactant. In a typical reaction, methylene blue and A-methyldiethanolamine were irradiated at 31°C, and the product characterized by GPC. 

TABLE 1. Effect of sensitizer concentration on the molecular weight of polybutyl acrylate using 0.0349M A-methyldiethanolamine as the photoinitiator. 

Table 17. Triplet life-time (t) of polysiloxanes containing cyclohexyl phenyl ketone as well as alkylphenone moieties and polymerization rate (Rp) of MMA in the presence or in the absence of A-methyldiethanolamine [86]...

Note It seems relevant that aqueous solutions of A-methyldiethanolamine (77), employed to remove H2S from hydrocarbon gases, gradually accumulate inter alia 1,4-dimethyl-, l-(2-hydroxyethyl)-4-methyl-, and l,4-bis(2-hydrox-yethyl)piperazine. 

Metabolism studies with ethanolamines have been undertaken in the context of their use as industrial chemicals. Following PC and IV administration of Y-mcthyldicthanolaminc in the rat, a major fraction of the absorbed dose was excreted as unidentified urinary metabolites, with some unchanged A-methyldiethanolamine (Leung et al, 1996). Triethanolamine was excreted predominantly unmetabolized in mice following both IV and percutaneous administration (Stott et al, 2000). 

Lee et al. (1990) studied the PV of EtOH-water mixtures by cationic-anionic interpenetrating polymer network (IPN) membranes. The cationic PU prepared by quaternizing the tertiary amine from A -methyldiethanolamine and the anionic acrylic copolymer from acrylic acid were used as the cationic and anionic components. The separation factor increased as the content of the anionic component in the membrane increased. The ion content in the membrane was also found to be an important factor for the optimum permseparation of water. Better performance was achieved by PEG-based PU as the cationic component of the IPN membrane. The highest selectivity was observed for the IPN membrane with 10 wt% of PEG-based PU. 

Mitsubishi Kasei (Tokyo, Japan) offers a methacrylate-based 5 pm anion exchanger exclusively for nonsuppressed conductivity applications under the trade name MCI Gel SCA04. An eluent mixture consisting of vanillic acid and A/-methyldiethanolamine has been developed especially for this column, and is... 

Figure 10.375 Separation of short-chain fatty acids in a "semilean" A/-methyldiethanolamine solution. Separator column lonPac AS10 eluent 3.5 mmol/L Na2B407 flow rate 1 mUmin detection suppressed conductivity injection volume 25 pL peaks (a) 1.9mg/L fluoride (1),...

Martin-Arbella, N Bretos, I., Jimenez, R Calzada, M.L., and Sirera, R. (2011) Metal complexes with A/-methyldiethanolamine as new photosensitive precursors for the low-temperature preparation of ferroelectric thin films. J Mater, Chem.,... 

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