Triethyl ammonium bromide

Note Examples are potassium salts of unbranched alkanoic acids, lecithin, certain polyisocyanates, cellulose derivatives with side-chains, such as (2-hydroxypropyl)cellulose, and cyanobiphenyl derivatives of alkyl(triethyl)ammonium bromide. 

Effects of added n-alkyl triethyl ammonium bromides upon the mechanical stability of natural rubber latex (9)... 

Some interesting results have recently become available for the effects of a range of n-alkyl triethyl ammonium bromides upon the mechanical stability of natural rubber latex. The number of carbon atoms in the alkyl group varied from 6 to 18. Figure 6 summarises the results. It is usually believed that the addition of cationic surfactants to an anionic latex such as natural rubber latex invariably leads to a reduction in colloid stability, the effect being attributed to adsorption of the cations with consequent partial neutralisation of the particle charge and reduction of the counterion cloud surrounding the particles. 

Whilst the results summarised in Figure 6 show that this expectation is often realised, they also show that small additions of an n-alkyl triethyl ammonium bromide whose alkyl group contains between approximately 8 and 12 carbon atoms can bring about a small increase in mechanical stability. In such cases, the increase in stability cannot possibly be attributed to enhance-... 

TMA = tetra-methyl ammonium, TPA = tetra-propyl ammonium, Et-Py- = N-ethyl pyridinium, DIQ-6 = 1,6 hexa-methylene bis (trimethyl ammonium bromide), DIQ-6 = 1,6 hexa-methylene bis (benzyldimethyl ammonium bromide) and DIQ-6 = 1,6 hexa-methylene bis (triethyl ammonium bromide). 

Cetyl triethyl ammonium bromide (CTAB) adsorption is widely used in carbon black industry (Janzen and Kraus, 1971 Kraus and Jansen, 1978 Bele et al., 1998). This method consists of making a suspension of a known mass of carbon black into a water CTAB solution of known concentration. Carbon black is then filtered and the quantity of adsorbed CTAB is determined by titration of the remaining CTAB in the filtrate. Surface area of carbon black is then deducted from the amount of CTAB adsorbed, using a previously determined calibration with a reference carbon black. 

On the contrary, PLA/OMMT nanocomposites exhibited a tensile strength of 45 Mpa, which shows an increase of 18% as compared to that of the matrix polymer. This indicates that the alkylammonium modification using hexadecyl triethyl ammonium bromide (HTAB) expands the clay galleries of NaMMT to facilitate easy penetration of PLA macromolecules into the interstitial spaces. According to Yoshida et al, in the case... 

Reddy et al. reported the synthesis of V-containing NCL-1 from a gel containing fumed sihca, NaOH, vanadyl sulfate and hexamethylene bis (triethyl-ammonium bromide). Incorporation of V is rather Hmited, the lowest Si/V ratio obtained being 150 [111]. Though the structure of NCL-1 is still unknown, adsorption and diffusivity experiments indicate a pore size close to that of mor-denite (ca. 7 A) [112]. Therefore, V-NCL-1 would represent the unique example of V incorporation in a large pore molecular sieve. 

Condvritol B Epoxide. The above bromopentol B is dissolved in 2 ml of water and adjusted to pH 10.5-11 with a few microliters of triethyl-amine. The solution is kept at room temperature for 60 min at this pH, readjusted with triethylamine, if necessary, diluted with 10 ml of water, and concentrated to 1 ml to remove excess triethylamine. The solution is stable at 4° for several weeks. It is not advisable to concentrate to dryness since the mixture of triethyl ammonium bromide and epoxide may show a partial reversion to bromopentol. 

Polypeptide Synthesis and Analysis. Sihca or controUed-pore glass supports treated with (chloromethyl)phenylethyltrimethoxysilane [68128-25-6] or its derivatives are replacing chloromethylated styrene—divinylbenzene (Merrifield resin) as supports in polypeptide synthesis. The sdylated support reacts with the triethyl ammonium salt of a protected amino acid. Once the initial amino acid residue has been coupled to the support, a variety of peptide synthesis methods can be used (34). At the completion of synthesis, the anchored peptide is separated from the support with hydrogen bromide in acetic acid (see Protein engineering Proteins). 

These fluoro quaternary bromides proved to be not very toxic. Triethyl 2-fluoroethyl ammonium bromide, for example, had a l.d. 50 for subcutaneous injection into mice of about 800 mg./kg. The low toxicity of these compounds may again provide useful evidence regarding their probable fate in the body. Itseems that the bond connecting the 2-fluoroethyl group with the rest of the molecule is not readily ruptured. In this connexion, however, the possibility of increased lability of the fluorine atom hi these less toxic compounds must not be overlooked. 

Potassium r-butoxide-Hexamethyl-phosphoric triamide, 252 Potassium r-butoxide-Xonotlite, 254 Potassium hydroxide, 258 Potassium hydroxide-18-Crown-6, 258 Potassium hydroxide-Tricaprylyl-methylammonium chloride, 258 Sodium hydroxide-Methyltrioctyl-ammonium chloride, 192 Sodium hydroxide-Triethyl(2-methyl-butyl)ammonium bromide, 239 Sodium hydroxide-N-(p-Trifluoro-methylbenzyl)cinchoninium bromide, 325... 

In the 2002 study of legal et al. [83], three different types of surfactants were used for synthesizing PA layer. Among the surfactants used, it is found that only triethyl benzyl ammonium bromide (TEBAB) could enhance the properties of resultant composite membrane, achieving 40% increase in the water flux upon 0.2 w/v% TEBAB added. The use of other surfactants such as trimethyl benzyl ammonium bromide (TMBAB) and triethyl benzyl ammonium chloride... 

Figure 2. Bending response for a silicon cantilever coated with self assembled monolayer of triethyl-12-mercaptododecyl-ammonium bromide on the gold surface of a microcantilever as a function of the change in concentration of...

Ribose derivatives. a-o-Ribofuranose i-phosphate was first obtained by the action of nucleoside phosphorylase on nucleosides . It has been prepared by treatment of 5-O-acetyl-D-ribofuranosyl i-bromide 2,3-cyclic carbonate with triethyl ammonium dibenzyl phosphate followed by removal of the protecting groups . 

S-D-Ribofuranose i-phosphate has been obtained by phosphorylation of 2,3,5-tri-0-benzoyl-j8-D-ribofuranosyl i-bromide with triethyl ammonium dibenzyl phosphate. ... 

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