Glycerol polyols

Glycerol, polyols (sorbitol, mannitol) Solvophobicity Affinity for polar regions Stabilizers of globular proteins and assembled organelles, decreasing for proteins of high polarity... 

Elastic and flexible potato starch-based films could be prepared fairly well using binary polyol mixtures as plasticizers but brittle films were obtained without plasticizer. Potato starch-based films plasticized with glycerol-polyol used and xylitol-sorbitol mixtures with content up to 40 and 50%, respectively, were easy to handle. Potato starch-based films were sticky with the glycerol-polyol content of 50% and thus difficult to handle. The thickness obtained for starch-based films was in the range of 33 to 74 /rm. 

Papain (and lipase) Amino Acid surfactants Ester or amide bond formation between arginine s a-carboxylic acyl group and fatty alcohols, glycerol (polyols), or fatty amines, respectively Infante et al., 2009... 

Properties Tan soft paste mild ammoniacal odor sol. in alcohols, ketones, glycols, glycol ethers, some hydrophobic soivs. such as fatly alcohols, esters, aliphatic, aromatic, and chlorinated hydrocarbons disp. in silicones, min. oil, veg. oils, glycerol, polyols insol. in water sp.gr. 0.850 0.05 dens. 7.41 Ib/gal m.p. 28-32 C add no. 85-105 alkali no. 75-iB5 pH 6-8 (5% in 50 50 waler IPA) 100% act. NeconBD [AIzo]... 

Humectants. In certain foods, it is necessary to control the amount of water that enters or exits the product. It is for this purpose that humectants are employed. Polyhydric alcohols (polyols), which include propylene glycol [57-55-6], C2Hg02, glycerol [56-81-5], C HgO, sorbitol [50-70-4], and mannitol [69-65-8], contain numerous hydroxyl groups (see Alcohols,polyhydric). Their stmcture makes them hydrophilic and... 

Because the total polyol is to be equimolar to PA, the glycerol from the soya oil must therefore be 0.375 mol, which gives 1.125 mol of soya fatty acids. Summarizing thus far ... 

This formulation does not meet the test of 50% oil length the oil content must be reduced. A reduction in oil causes a corresponding reduction in glycerol, consequendy, free glycerol is added to make up the loss. If Mpg = a , and = z and total polyols is to be equimolar to dibasic acids,... 

Ideally, two moles of polyol react with one mole of triglyceride to form three moles of monoester. In reaUty, the reaction reaches an equiUbrium, whereby some amount of di- and tri-esters and neat polyol, including glycerol and the added polyol, coexist in the reaction mixture. The compositions of the alcoholysis products at equiUbrium from soya oil and glycerol (1 2 mole ratio), and soya oil and monopentaerythritol have been reported (33) as follows ... 

Some of the simplest polyols are produced from reaction of propylene oxide and propylene glycol and glycerol initiators. Polyether diols and polyether triols are produced, respectively (27) (see Glycols). 

The newer HFC refrigerants are not soluble in or miscible with mineral oils or alkylbenzenes. The leading candidates for use with HFC refrigerants are polyol ester lubricants. These lubricants are derived from a reaction between an alcohol and a normal or branched carboxyflc acid. The most common alcohols used are pentaerythritol, trimethylolpropane, neopentjlglycol, and glycerol. The acids are usually selected to give the correct viscosity and fluidity at low temperatures. 

The structure of these products is uncertain and probably depends on pH and concentrations in solution. The hydroxyl or carboxyl or both are bonded to the titanium. It is likely that most, if not all, of these products are oligomeric in nature, containing Ti—O—Ti titanoxane bonds (81). Thek aqueous solutions are stable at acidic or neutral pH. However, at pH ranges above 9.0, the solutions readily hydroly2e to form insoluble hydrated oxides of titanium. The alkaline stabiUty of these complexes can be improved by the addition of a polyol such as glycerol or sorbitol (83). These solutions are useful in the textile, leather (qv), and cosmetics (qv) industries (see Textiles). 

Polyurethane foams are formed by reaction with glycerol with poly(propylene oxide), sometimes capped with poly(ethylene oxide) groups with a reaction product of trimethylolpropane and propylene oxide or with other appropriate polyols. A typical reaction sequence is shown below, in which HO—R—OH represents the diol. If a triol is used, a cross-linked product is obtained. 

Reduction. Mono- and oligosaccharides can be reduced to polyols (polyhydroxy alcohols) termed alditols (glycitols) (1) (see Sugar alcohols). Common examples of compounds in this class ate D-glucitol (sorbitol) [50-70-4] made by reduction of D-glucose and xyhtol [87-99-0] made from D-xylose. Glycerol [56-87-5] is also an alditol. Reduction of D-fmctose produces a mixture of D-glucitol and D-mannitol [69-65-8],... 

Aliphatic Glycidyl Ethers. Aliphatic epoxy resins have been synthesized by glycidylation of difunctional or polyfunctional polyols such as a 1,4-butanediol, 2,2-dimethyl-l,3-propanediol (neopentyl glycol), polypropylene glycols, glycerol, trimethylolpropane, and pentaerythritol. 

Surface-Active Agents. Polyol (eg, glycerol, sorbitol, sucrose, and propylene glycol) or poly(ethylene oxide) esters of long-chain fatty acids are nonionic surfactants (qv) used in foods, pharmaceuticals, cosmetics, textiles, cleaning compounds, and many other appHcations (103,104). Those that are most widely used are included in Table 3. 

The typical alkyd resin (see above) is eomprised of three basic components an aromatic diacid such as phthalic anhydride which together with a polyol such as glycerol, forms the backbone of the resin molecule and along which are distributed the fatty acids derived from vegetable oils. The solubility, film hardness and colour of alkyd resins depend on the nature of the modifying fatty acid which in most cases contributes some colour to the film. 

Alkyd resin synthesis. This synthesis consists of two steps. In the first step, a triglyceride oil is reacted at ca. 250°C with polyols, such as glycerol or pentaery-thritol, in tire presence of a basic catalyst to form a monoglyceride. In the second step, phthalic anhydride, with or without another dibasic acid such as maleic anhydride, is added to the reaction medium and reacted at high temperature. The resulting product is a branched polyester (Scheme 2.56). 

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