Stearic acid and derivs

Metal sulfonate-containing ethylene-propylene-diolefin ter-polymers (EPDM) were plasticized with stearic acid and derivatives for the reduction of the melt viscosities of these ionomers through interaction with the very strong ionic associations. Substantial improvements in melt flow were achieved with stearic acid and the zinc, lead, and ammonium stearates, while other metal stearates were ineffective. Zinc stearate and lead stearate not only markedly improved melt flow but, remarkably, also enhanced the mechanical properties of the plasticized systems. These unique additives were fully compatible with the EPDM ionomers and provided thermoelastic systems with excellent physical properties and ready processability. 

Lubricant Potential of Stearic Acid AND Derivatives for the Production Tablets by Direct Compression... 

Figure 1. Chemical structure of stearic acid and derivatives (A) Stearic acid, (B) magnesium stearate and (C) sodium stearyl fumarate.

Figure 3. Powder X-Rays difractograms of stearic acid and derivatives.

From lubricant applications to controlled released devices, the progress in stearic acid and derivatives are considered as challenging and groundbreaking. Future innovations in stearic acid-based lubricants could lead to the development of high-tech pharmaceutical excipients and devices which improve the production of pharmaceutical dosage forms. 

Table I. Monohydroxy- and dihydroxy-deuterated stearic acids and derivatives...

This section gives a brief description of other common compounding ingredients such as stearic acid and derivatives, resins, processing aids, and blowing agents. 

Biosynthesis of Unsaturated Fatty Acids. In the mammalian tissues, the forma-tion of monoene fatty acids is only possible. Oleic acid is derived from stearic acid, and palmitooleic acid, from palmitic acid. This synthesis is carried out in the endoplasmic reticulum of the liver cells via the monooxigenase oxidation chain. Any other unsaturated fatty acids are not produced in the human organism and must be supplied in vegetable food (plants are capable of generating polyene fatty acids). Polyene fatty acids are essential food factors for mammals. 

The FT-IR technique using reflection-absorption ( RA ) and transmission spectra to quantitatively evaluate the molecular orientation in LB films is outlined. Its application to some LB films are demonstrated. In particular, the temperature dependence of the structure and molecular orientation in alternate LB films consisting of a phenylpyrazine-containing long-chain fatty acid and deuterated stearic acid (and of their barium salts) are described in relation to its pyroelectricity. Pyroelectricity of noncentrosymmetric LB films of phenylpyrazine derivatives itself is represented, too. Raman techniques applicable to structure evaluation of pyroelectric LB films are also described. 

In the method, a weighed portion of a sample of coke dried at 110°C (230°F) and crushed to pass a No. 200-mesh sieve, mixed with stearic acid, and then milled and compressed into a smooth pellet. The pellet is irradiated with an x-ray beam and the characteristic x-rays of the elements analyzed are excited, separated, and detected by the spectrometer. The measured x-ray intensities are converted to elemental concentration by using a cahbration equation derived from the analysis of the standard materials. The K spectral lines are used for aU the elements determined by this test method. This test method is also apphcable to the determination of additional elements provided that appropriate standards are available for use and comparison. 

Concentrate the remaining volume to near dryness by nitrogen blowdown at room temperature. Add several milliliters of distilled ether, concentrate to near dryness in a water bath, and repeat four or five more times to remove HC1. Esterify with diazomethane (2) and analyze by capillary GC-FID for stearic acid and 2,4-dichlorophenol (5-chlorouracil also gave a derivative with diazomethane). Retain all concentrate after GC-FID analysis for possible HPLC analysis. 

Dynamic mechanical analysis has been used to study the compatibility of ester lubricants, and stearic acid and its derivatives (403, 420). On the basis of a PVC melt flow test (ASTM D 3364), the effect of lubricants on processing has been determined (313). 

This work aims to produce mixed calcium carboxylate stabilisers for use in place of calcium stearate for the stabilisation of PVC. The new stabilisers are based on mixed salts of stearic acid with derivatives of phthalic or maleic acid and also with branched alpha, alpha-branched carboxylic (C12-C16) acids, noted for their lower cost and adequate effectiveness. Test results are examined in detail for the performance of these stabilisers in terms of service properties, processability, and stabilising action. 2 refs. (Translated from Plasticheskie Massy, No.5, 2000, p.19)... 

As the main component, it provides the actual matrix to which lipophilic or water-insoluble substances such as stearic acid and stearyl alcohol [475-476], cellulose derivatives [476], starch [475] or calcium hydrogen phosphate [474] are added. 

This is soluble in water and can be isolated from the raw wool by aqueous extraction. It contains potassium salts of fatty acids, such as oleic and stearic acids, and potassium carbonate is also present. The simpler organic acids, such as acetic, lactic, butyric, valeric, and capronic acids, have also been found both in the free state and as their potassium salts. Amino acids such as leucine, glycine, and tyrosine have been detected. Suint, therefore, is a complex mixture this might be expected because it is derived from sweat, which is known to be one of the means by which an animal discards unwanted waste products of its metabolism. 

Palmitic and stearic acids are derivatives of the paraffin series of hydrocarbons and therefore are saturated. Oleic acid is unsaturated, having the structure represented by CH3(CH2)7.CH=CH.(CH2)7.COOH. When reduced with hydrogen in the presence of a catalyst it is converted to stearic acid. Unsaturated fatty acids are readily oxidized to dihydroxy compounds CH3(CHj),.CH CH.(CHj),C00H + Hj04-0... 

The plasticizing effects of a larger number of metal stearates on the zinc sulfonate ionomer were examined, and the results are given in Table III in terms of flow and mechanical properties. Lead stearate, zinc stearate, and ammonium stearate significantly improved melt flow along with the stearic acid control. The barium, magnesium, sodium, lithium, and calcium stearates showed little, if any, improvement in melt flow. Of the four melt flow improvers, both stearic acid and ammonium stearate exerted deleterious effects on tensile properties. Only the zinc and lead stearates substantially improved tensile properties. Thus, while zinc stearate is not unique, the number of fatty acid derivatives that improve both melt flow and mechanical properties is limited. 

Synonyms Anhydro-d-giucitol monooctadecanoate Anhydrosorbitoi monostearate Anhydrosorbitoi stearate SMS Sorbitan, esters, monooctadecanoate Sorbitan monooctadecanoate Sorbitan monostearate Definition Monoester of stearic acid and hexitol anhydrides derived from sorbitol... 

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