Glycerol bonding

Triglyceride Fat molecule consisting of a molecule of glycerol bonded to three fatty acids. 

A fat molecule consists of one molecule of glycerol, bonded by dehydration synthesis (the loss of water) to three fatty acid molecules (this is a triacylglycerol. Figure 1.4). Fatty acids are... 

SynChropak was the first commercial bonded silica of this type, followed by LIChrosorb DIOL and LiChrospher DIOL. Protein-Pak materials as well as Sl-Polyol are similar in surface composition. Recently a specifically pH-stabIIized, glycerol-bonded silica has been introduced on the market Zorbax Bio-Series 6F 250. The most popular are the TSK gel SW types which are thought to be bonded with a glycerol-ether moiety. On annealing from 400 to 823 K, the TSK gel SW 3000 showed a weight loss of ca. 15X while the carbon content was 7.3X, Indicating on oxygen-rich... 

Body fat is a triglyceride composed of glycerol bonded to three... 

The enzymatic hydrolysis of lecithin to fatty acids, glycerol, phosphoric acid, and choline requires the participation of some four enzymes. The enzymes attacking the various bonds of a lecithin molecule are summarized in Table XIV. The bonds which are cleaved are referred to by number in the lecithin formula shown below the same numbers are used in Table XIV to indicate the respective enzymes involved. The cleavage of the fatty acid-glycerol bond, as represented by diagonal lines 1 and 2, is based on hydrolysis studies of simple esters. Diagonal lines 3 and 4 are only provisional, as presumably either a P—0 or C—O bond to phosphate could be cleaved. 

Fats and oils are triglycerides, triesters composed of glycerol bonded by ester linkages to three fatty acids. Like fatty acids, triglycerides can be saturated (fats) or unsaturated (oils). 

Other lipids include phospholipids, made up of a glycerol bonded to two nonpolar fatty acids and a polar phosphate group, used in animal cell membranes glycohpids, similar to phospholipids but with a sugar molecule as their polar head and steroids, four-ringed hpids that include cholesterol and sex hormones. 

Most naturally occurring triacylglycerols contain glycerol bonded to two or three different fatty acids, typically palmitic acid, oleic acid, linoleic acid, and stearic acid. For example, a mixed triacylglycerol might be made from stearic acid, oleic add, and palmitic acid. One possible structure for this mixed triacylglycerol follows ... 

When a mixture of aniline, nitrobenzene, glycerol and concentrated sulphuric acid is heated, a vigorous reaction occurs with the formation of quinoline. It is probable that the sulphuric acid first dehydrates the glycerol giving acrolein or acraldehyde (A), which then condenses at its double bond with the amino group of the aniline to give acrolein-aniline (B), The latter in its enol... 

Esters can participate m hydrogen bonds with substances that contain hydroxyl groups (water alcohols carboxylic acids) This confers some measure of water solubil ity on low molecular weight esters methyl acetate for example dissolves m water to the extent of 33 g/100 mL Water solubility decreases as the carbon content of the ester increases Fats and oils the glycerol esters of long chain carboxylic acids are practically insoluble m water... 

Fats and oils (Section 26 2) Tnesters of glycerol Fats are solids at room temperature oils are liquids Fatty acid (Section 26 2) Carboxylic acids obtained by hydro lysis of fats and oils Fatty acids typically have unbranched chains and contain an even number of carbon atoms in the range of 12-20 carbons They may include one or more double bonds... 

Fig. 8. Reactions of ttiglycetides at double bonds in the alkyl chain. R represents the glycerol backbone.

In the reaction of aEyl alcohol with an aqueous chlorine solution, addition of hypochlorous acid to the double bond of aEyl alcohol yields glycerol monochlorohydrin and as a by-product, glycerol dichlorohydrin. Thus, a poor yield of glycerol monochlorohydrin is obtained (8). To improve the yield of glycerol monochlorohydrin, addition of sodium carbonate in an amount equivalent to that of the hydrogen chloride in the aqueous chlorine solution, has been proposed (9). 

Carboxylate soaps are most commonly formed through either direct or indirect reaction of aqueous caustic soda, ie, alkaH earth metal hydroxides such as NaOH, with fats and oils from natural sources, ie, triglycerides. Fats and oils are typically composed of both saturated and unsaturated fatty acid molecules containing between 8 and 20 carbons randomly linked through ester bonds to a glycerol [56-81-5] backbone. Overall, the reaction of caustic with triglyceride yields glycerol (qv) and soap in a reaction known as saponification. The reaction is shown in equation 1. 

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). 

Addition to the Double Bond. Chlorine, bromine, and iodine react with aHyl chloride at temperatures below the inception of the substitution reaction to produce the 1,2,3-trihaLides. High temperature halogenation by a free-radical mechanism leads to unsaturated dihalides CH2=CHCHC1X. Hypochlorous and hypobromous acids add to form glycerol dihalohydrins, principally the 2,3-dihalo isomer. Dehydrohalogenation with alkah to epicbl orobydrin [106-89-8] is ofgreat industrial importance. 

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