Polyethylene glycol solubihty

In certain brilliantine compositions, vegetable and animal oils are used as substitutes for mineral oil. In these systems, because of their potential for rancidity, antioxidants must be included. Other alternatives to mineral oils that have found utiHty in brilliantines are the polyethylene glycols which come in a variety of solubiHties and spreading properties. Use of these materials offers the advantage of chemical stabiHty to rancidity. Other additives found in brilliantines to improve their aesthetics include colorants, fragrance, medicated additives, lanolin, and fatty acid esters. 

LiAlH is soluble in ethers, 35-40 g/100 g diethyl ether at 25°C. Solubihty in THF, the other common solvent for LiAlH, is 13 g/100 g at 25°C. Polyethylene glycol diaLkyl ethers are also good solvents. 

The solvent can be tailored to provide selective acid gas removal based on the Hquid—gas solubiHties. For example, the Selexol process, Hcensed by Union Carbide Corporation, uses the dimethyl ether of polyethylene glycol (DMPEG) to provide high hydrogen sulfide selectivity. The solubiHty of hydrogen sulfide in DMPEG is 8—10 times that of carbon dioxide. 

Esters polyethylene glycol or ethylene glycol are called PEG esters. A PEG ester s solnbiHty is determined by the nnmber of PEG molecules reacted per molecule of acid. PEG 6 oleate for instance has six molecules of PEG reacted with one molecule of oleic acid. As the number of polar, PEG molecules per acid molecule increases the water solubihty/HLB is increased PEG 8 oleate is more soluble than PEG 6 oleate. The cosmetic chemist will often use blends of glyceryl esters and a PEG ester with high and low HLB values to determine the required polarity to emulsify various fats and oils. The many types of emulsifiers are too numerous to hst here, ho Never McCutcheon s Emulsifiers and Detergents is an excellent source for a more complete Hsting. 

Water sensitivity and solubihty can be conveniently regulated by the use of a combination of plasticizers. In hotmelts that are water sensitive, two groups of plasticizers are used in different proportions depending on required properties. Larger amounts of water soluble plasticizers such as polyethylene glycol mono- and di-laureates increase water sensitivity. Addition of larger amounts of water insoluble plasticizers, such as 2-ethyl-hexyl diphetyl phosphate or butyl benzyl phthalate, increases the hydrophobic properties of hotmelt. ... 

Several industries including the aerospace industry use rapid prototyping. Prototypic materials use polyethylene glycol having molecular weight of 600 daltons as plasticizer for poly(2-ethyl-2-oxaline), PEO, a polymer used for making prototypes. Plasticizer enhances overall water solubihty of PEO and its dissolution rate." ... 

Another treatment that has been used for TFA is to apply polyethylene glycol (PEG) 400. The thinking might have been the TFA would be more soluble in PEG 400 than in water/tissue and that the PEG 400 would then extract the TFA from tissue. The degree to which this is true would depend upon the solubihty of TFA in various solvents and the solubility of PEG 400. Here are statements about the solubility of each substance ... 

Materials that typify thermoresponsive behavior are polyethylene—poly (ethylene glycol) copolymers that are used to functionalize the surfaces of polyethylene films (smart surfaces) (20). When the copolymer is immersed in water, the poly(ethylene glycol) functionaHties at the surfaces have solvation behavior similar to poly(ethylene glycol) itself. The abiHty to design a smart surface in these cases is based on the observed behavior of inverse temperature-dependent solubiHty of poly(alkene oxide)s in water. The behavior is used to produce surface-modified polymers that reversibly change their hydrophilicity and solvation with changes in temperatures. Similar behaviors have been observed as a function of changes in pH (21—24). 

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