Polyethylene glycol as solvent

Sauvagnat, B., Lamaty, E, Lazaro, R. and Martinez, J., Polyethylene glycol) as solvent and polymer support in the microwave assisted parallel synthesis of aminoacid derivatives, Tetrahedron Lett., 2000,41,6371-6375. 

Polyethylene glycols can also be used to enhance the aqueous solubility or dissolution characteristics of poorly soluble compounds by making solid dispersions with an appropriate polyethylene glycol. Animal studies have also been performed using polyethylene glycols as solvents for steroids in osmotic pumps. 

Sulfones may also be obtained by alkylation of sulfinate salts (79). The sulfinate anion is an ambidentate nucleophile consequently, alkylation can occur either on sulfur to give the sulfone (74) or oxygen to yield the sulfinate ester (80) (Scheme 31). The reactions of (79) with alkyl iodides in polyethylene glycols as solvents generally afford good yields of the sulfones (74). 

In this type of reaction the active drug undergoes decomposition following reaction with the solvent present. Usually the solvent is water, but sometimes the reaction may involve pharmaceutical cosolvents such as ethyl alcohol or polyethylene glycol. These solvents can act as nucleophiles, attacking the electropositive centers in drug molecules. The most common solvolysis reactions encountered in pharmaceuticals are those involving labile carbonyl compounds such as esters, lactones, and lactams (Table 1). 

Sepasolv MPE [Methyl isopropyl ester] A variation on the Selexol process, using the methyl isopropyl ethers of polyethylene glycol as the solvent. Developed by BASF. Four commercial plants were operating in 1985, removing hydrogen sulfide from natural gas. Wolfer, W., Hydrocarbon Process., 1982,61(11), 193. 

These are dispersants (e.g., amines, fatty acids, polycarboxylic acids), binders (e.g., wax polyacrylate, polyvinyl alcohol), plasticisers (e.g., stearic acids, dibutyl phthalate, polyethylene glycol) and solvents (e.g., water, organics) [244-250]. They are needed to prepare a suitable suspension or slurry for the subsequent shaping step. They must evaporate during a presintering treatment without causing failures (Table 9). Suspensions as well as slurries should have an uniform distribution of the Si3N4 particles, adequate viscosity, and no... 

Haimov A, Neumann R (2002) Polyethylene glycol as a non-ionic liquid solvent for polyoxometalate catalyzed aerobic oxidation. Chem Commun 8 876-877... 

Increased selectivity has also been obtained using polyethylene glycol as complexing agent.Using toluene as solvent, the authors report a 1 10 para. ortho ratio in the formylation of phenol. 

Abribat. B. Le Bigot. Y. Seleetive etherification of hydroxylated functions in the absenee of solvent. H. Polyethylene glycol as catalyst. Tetrahedron 1993. 53 (6). 2119-2124. 

The critical diagram M vs retention time for a short RP-18 column of 60 mm length is shown in Fig. 7A. At acetonitrile concentrations > 47 vol.% in the solvent mixture, the retention time decreases as the molar mass of the PEO calibration sample increases retention corresponds to a size-exclusion mode. The reverse behaviour, i.e. the adsorption mode, is obtained at acetonitrile concentrations < 45 vol.%. The critical point of adsorption is operating at an eluent composition of acetonitrile-water 46 54 v/v, where separation is accomplished exclusively with respect to the functional endgroups- (see Fig. 7B). For the alkoxy-terminated PEOs, two distinctively different fractions are obtained, due to the formation of polyethylene glycol as an unwanted by-product. In the case... 

Tara gum is used as an appetite suppressant and as a binding agent and disintegrating agent in compressed tablets. It is also used to thicken various cosmetic products such as lotions and creams [45-49]. Some excipients that improve solubility are hydrophilic solvents [50, 51] such as propylene glycol and polyethylene glycol. Hydrophobic solvents are vegetable oils, triacetin, and diethyl phthalate. Tara gum is used as polymer emulsifer with polysorbates and vitamin E [52, 53]. 

Modifications are possible to give more unusual properties to the resin. Inclusion of polyethylene glycol as polyol produces an alkyd which is water dispersible. One such alkyd has been used in white spirit-based gloss house paint. This paint can be washed from brushes using a weak detergent solution in water without requiring the use of organic solvent. 

As noted before, amine oxides can be easily adapted for use in solid systems, including their use in bar soaps. Amine oxide computability with water-sensitive systems is accomplished by reacting the tertiary amine with aqueous hydrogen peroxide, using liquid polyethylene glycol as the sole organic solvent [64]. 

Jiang et al. (2008) prepared a composite material from PHBV and cellulose using solvent casting. They dissolved PHBV, cellulose nanowhiskers and polyethylene glycol (as a compatibilizer) in A,A-dimethylformamide (DMF), and cast the solution on a glass plate at 50 °C in order to realize DMF evaporation. The final material showed a homogeneous dispersion of cellulose nanowhiskers, which improved mechanical properties. 

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