1.2- hydroxy stearic acid

Lithium hydroxide with 12-hydroxy-stearic acid (or hydrogenated castor oil) they form the family of lithium greases very commonly used for general lubrication and bearing lubrication. 

Specialty waxes include polar waxes for more polar adhesive systems. Examples would be castor wax (triglyceride of 12-hydroxy stearic acid) or Paracin wax N- 2 hydroxy ethyl)-12-hydroxy stearamide) which are used in polyester, polyamide, or with high VA EVA copolymer-based systems. Other common polar waxes are maleated polyethylenes, which are used to improve the specific adhesion of polyethylene-based adhesives, and low molecular weight ethylene copolymers with vinyl acetate or acrylic acid, which are used to improve low temperature adhesion. High melting point isotactic polypropylene wax (7 155°C) and highly refined paraffin wax (7,n 83°C) are used where maximum heat resistance is critical. Needless to say, these specialty waxes also command a premium price, ranging from 2 to 5 times that of conventional paraffin wax. 

Figure 12.12 THM GC/MS curves of a Winsor Newton lemon alkyd paint (a) and of an alkyd sample taken from Fontana s work Concetto spaziale (1961) (b). Peak assignments 1, 1,3 dimethoxy 2 propanol 2, 1,2,3 trimethoxy propane 3, 3 methoxy 1,2 propandiol 4, 4 chloro benzenamine 5, 3 methoxy 2,2 bis(methoxymethyl) 1 propanol 6, 3 chloro N methyl benzenamine 7, 3 methoxy 2 methoxymethyl 1 propanol 8, 4 chloro N methyl benzenamine 9, phthalic anhydride 10, 3 chloro 4 methoxy benzenamine 11, suberic acid dimethyl ester 12, dimethyl phthalate 13, azelaic acid dimethyl ester 14, sebacic acid dimethyl ester 15, palmitic acid methyl ester 16, oleic acid methyl ester 17, stearic acid methyl ester 18, 12 hydroxy stearic acid methyl ester 19, 12 methoxy stearic acid methyl ester 20, styrene 21, 2 (2 methoxyethoxy) ethanol 22, 1,1 oxybis(2 methoxy ethane) 23, benzoic acid methyl ester 24, adipic acid dimethyl ester 25, hexadecenoic acid methyl ester 26, dihydroisopimaric acid methyl ester 27, dehydroabietic acid methyl ester 28, 4 epidehydroabietol...

Crosslinked polymer particles with a rather complex structure, which have also been designated by the name microgels and recommended as components of metal effect paints, consist of carboxyl-terminated oligoesters of 12-hydroxy stearic acid which were reacted with glycidyl methacrylate, subsequently copolymerized with MMA and hydroxymethyl methacrylate and then crosslinked by hydroxy melamine [346]. 

Figure 31. ir-A curves for D-12-hydroxy-stearic acid (- - -), D,L-12-hydroxyste-aric acid (- - - -) and stearic acid ( ). From Tachibana and Hori (82). Permission of Academic Press, Inc. 

Elastomer/glyceride of 12-hydroxy stearic acid Stearic acid... 

Bittner, B., et al. 2002. Improvement of the bioavailability of colchicine in rats by co-administration of D-alpha-tocopherol polyethylene glycol 1000 succinate and a polyethoxylated derivative of 12-hydroxy-stearic acid. Arzneimittelforschung 52 684. 

The data of Mewis et al. (1989) for poly(methyl methacrylate) spheres stabilized by poly(12-hydroxy stearic acid) and dispersed in decalin conform... 

Solutol HS 15 is a water-soluble non-ionic solubilizer and is a mixture of approximately 70% lipophilic molecules consisting of polyglycol mono- and di-esters of 12-hydroxy stearic acid, and approximately 30% hydrophilic consisting of PEG. Solutol HS 15 is in rV and oral formulations in various countries. In IV formulations, Solutol HS-15 is used at concentrations... 

Hydroxy stearic acid and polybenzylglutamate were the classical cases of relatively simple molecules that produced twisted fibers, till the burst of reports on other examples, viz. amino acid amphiphiles, diacetylenic phospholipids, and gluconamides started in the mid-1980s. The handedness of chiral assemblies can be determined from electron micrographs, provided that care is taken to manipulate grids, specimens, films, and image scanners in a consistent way. It was not till the... 

Figure 14 shows the variation of the steady shear relative viscosity at the high shear limit with the effective volume fraction as defined by equation 46 for poly(methyl methacrylate) (PMMA) suspensions of different sizes in decalin sterically stabilized by means of grafted poly (12-hydroxy stearic acid) chains with a degree of polymerization of 5. The stabilizing polymer layer thickness is 9 1 nm, in particular, A = 9 nm... 

In nature one also finds chiral fatty acid or fatty alcohol derivatives with a hydroxyl or amino substituent at the alkyl chain. Common examples are given in Table 2.2.2 of the fatty acids in cheap commercial castor oil (a fat mixture) consist of ricinoleic acid (12-/ -hydroxy-9-Z-octadecene-carboxylic acid). The hydrogenation product (R)-12-hydroxy-stearic acid is the cheapest chiral fatty acid (about 100/g). Sphingosin (2-S-amino-4-E-octadecene-l,3-R-diol) is a chiral a--arnino-diol, which is found in large amounts in nerve tissue ( 5,000/g). Chirality is expensive, if it is localized within the hydrophobic chain. 

CAS 141-23-1 EINECS/ELINCS 205-471-8 Synonyms 12-Hydroxyoctadecanoic acid, methyl ester 12-Hydroxystearic acid methyl ester Methyl 12-hydroxyoctadecanoate Methyl 12-hy-droxystearate Methyl 12-hydroxy stearic acid Definition Ester of methyl alcohol and hydroxystearic acid Empiricai CisHseOj Formuia C16H34OHCOOCH3... 

Methyl 12-hydroxystearate Methyl 12-hydroxy stearic acid. See Methyl hydroxystearate... 

Methyl 12-hydroxystearate Methyl 12-hydroxy stearic acid. See Methyl hydroxystearate Methyi icinoi. See Methoxyethanol N,N -Methylidenebisacrylamide. See Methylene bisacrylamide... 

Figure 17-4. Dependence of the n umber-average degree of polymerization ICn on the time / (min) in the polycondensation of 12-hydroxy stearic acid at 152.5° C with 0.01 molp-toluene sulfonic acid / mol base unit as catalyst. — Reaction progress after the removal of unused catalyst and renewed addition of the same catalyst/functional group molar ratio as at the start of the polycondensation. (After C. E. H. Bawn and M. B. Huglin.)...

In a recent report on synthesis of silica [190], a reverse emulsion was prepared with isooctane as the continuous oil phase and an aqueous solution of HCl or HNO3 (catalyst) as the droplet phase. Tetraethyl orthosilicate was added to the emulsion it diffused from the oil phase to the droplets, underwent hydrolysis/ condensation reactions and formed silica gel particles. The reaction by-product ethanol decreased the stability of the emulsion. To avoid this, block copolymer surfactants Atlox and Hypermer were used (A-B-A type, where A = poly-12-hydroxy stearic acid and B = polyethylene oxide). 

The data of Mewis et al. (39) and d Haene (40) for poly(methyl methacrylate) spheres stabilized by poly( 12-hydroxy stearic acid) and dispersi in decalin correlate reasonably well with results for hard spheres for low to moderate volume fractions, although the critical stress is somewhat smaller. For highly concentrated dispersions, however, packing constraints cause some interpenetration of the layers at rest and viscous forces at high shear rates drive the particles even closer together. Consequently, the effective layer thickness decreases with increasing 0 and Pe, the dimensionless shear rate. 

P450 4F2 catalyzes co-hydroxylation of several lipids, including leukotriene B4 [1596, 1601], arachidonic and [1545], and 6-/ranx-lenkotriene B4, lipoxin A4, 8-hydroxyeicosatetraenoic acid, 12-hydroxyeicosatetraenoic acid, and 12-hydroxy stearic acid [1602], The physiological relevance of some of these reactions is of interest, but the effects of variability of P450 4F2 have not been demonstrated. Part of the interest lies in the fact that leukotriene B4 is a potent proinflamma-tory agent [1595, 1596],... 

Stearic and 12-hydroxy stearic acids were extracted from lubricating greases and then separated on a C[g column (refractive index detector) using a 70/30 THF/water (0.1% TFA) mobile phase [823]. Elution was complete in <8 min. Four grease samples were analyzed and the chromatograms were shown. The resulting sample contents (3-13% by weight) were tabulated. 

Another interesting model system is a dispersion of polymethylmetacrylate (PMMA) particles that are sterically stabilized with poly-12-hydroxy stearic acid in solvents such as decalin, sometimes mixed with tetrahn in order to match solvent and particle refractive indices. Early synthesis of and studies with these particles were performed in Bristol [9, 10]. These systems exhibit fluid to solid phase transitions when the particle volume fraction exceeds about 0.5. 

The reaction rate constant (at 160.5 C) for the polycondensation reaction of 12-hydroxy stearic acid... 

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