Stearic acid, magnesium salt

Magnesium octadecanoate octadecanoic acid, magnesium salt stearic acid, magnesium salt. 

Stearic acid, lauryl ester. See Lauryl stearate Stearic acid, lead salt. See Lead stearate Stearic acid, lithium salt. See Lithium stearate Stearic acid, magnesium salt. See Magnesium stearate... 

Ester formation with hydroxyl-containing APIs has been observed for acid salts (e.g., succinic acid, citric acid, formic acid, acetic acid, etc.) as well as excipients (e.g., stearic acid, magnesium stearate). See Figure 85 for an example of the reaction of a hydroxyl group with succinic acid (124). 

Some of the more common antifrictional agents are listed in Table 10. Many of these are hydrophobic and may consequently affect the release of medicament. Therefore, lubricant concentration and mixing time should be kept to the absolute minimum. Lubricants may also reduce significantly the mechanical strength of the tablet (see Fig. 12) [29,81]. Stearic acid and its magnesium and calcium salts are widely used, but the... 

Calcium, magnesium, and zinc salts of stearic acid... 

Interestingly, in a situation where either magnesium stearate or stearic acid forms a component in the formulation, the organic medicinal compound which is acidic (amobarbital) cannot be extracted with NaOH solution for obvious reason that sodium stearate shall also be extracted along with the salt of the organic acid. Therefore, instead a saturated solution of Ba(OH)2 is employed thereby the insoluble precipitate of barium stearate may be discarded by filtration. 

Amines are particularly prone to reaction with excipients and salt counterions, as shown in Figure 45 for tartaric acid. The potential for a reaction with magnesium stearate or stearic acid is particularly of concern with an API containing a primary amine. In the case of norfloxacin, formation of a stearoyl derivative was observed in tablets containing magnesium stearate after prolonged storage at 60°C (Fig. 46) (81). 

Melamine resins are used from this group of thermosets for the manufacture of food contact materials. The melamine can be used in mixtures with urea and in some applications with phenol (< 1 %). The polymerization process is catalyzed in the presence of organic acids (e.g. acetic acid, lactic acid, tartaric acid, citric acid), hydrochloric acid, sulfuric acid, phosphoric acid, sodium and potassium hydroxide, ammonia, calcium or magnesium hydroxide as well as salts of these substances (total < 1 %) which cause the elimination of water and lead to a cured resin system. Stearic acid can be used as a lubricant as can zinc, calcium and magnesium salts, esters of montanic acid with ethandiol and 1,3-butandiol, as well as silicone oil (total < 1 %). 

Lubricants act by interposing an intermediate layer between the tablet constituents and the die wall, to prevent adherence of the granules to the punch faces and dies. Thus, they ensure smooth ejection of the tablet from the die. In addition, many lubricants also enhance the flow properties of the granules. Stearic acid and its magnesium and calcium salts are widely used. The most effective lubricants, such as magnesium stearate, are very hydrophobic and can also prevent wetting of powders and hence retard dissolution (Figure 6.9). 

PROP Consists of aluminum, calcium, magnesium, potassium, and sodium salts of capric, captyUc, lauric, myristic, oleic, palmitic, and stearic acids manufactured from fats and oils derived from edible sources. 

The thermal decarboxylation of a mixture of barium salts has been used to prepare unsymmetrical ketones the yields are not stated. The earlier procedure has been modified by carrying out the reaction in vacuo in an iron flask. Glass reaction vessels are inferior. In this manner, a large number of the high-molecular-weight methyl ketone s, C9, C,o, C,j-C , and C, are prepared in 54-67% yields. Cyclopentanone has been synthesized in 80% yield by distillation of adipic acid from barium hydroxide at 295°. In a study of metallic oxides and carbonates, magnesium oxide is preferred for the liquid-phase ketonization of stearic acid at 330-360° (95%). A convenient method for the preparation of dibenzyl ketone is the reaction of phenylacetic acid, acetic anhydride. 

Fatty-acids, salts and esters Aluminum monostearate, calcium stearate, ethyl oleate, isopropyl myristate, isopropyl palmitate, magnesium stearate, oleic acid, polyoxyl 40 stearate, proprionic acid, sodium stearate, stearic acid, purified stearic acid, and zinc stearate... 

Palmitic acid and stearic acid are colorless, wax-like substances, which melt at 63° and 69°, respectively. They are insoluble in water, but dissolve in organic solvents. The sodium and potassium salts of the acids are soluble in water, while those of calcium, magnesium, and the heavy metals are insoluble. Both acids have the normal structure, that is, the alkyl radicals which they contain, C15H31, and C17H3B, respectively, consist of carbon atoms united in a straight chain. 

Hard soaps consist essentially of the sodium salts of palmitic, stearic and oleic acids. As the calcium and magnesium salts of these acids are insoluble in water, soap does not immediately pass into solution and form a lather with hard water. The soap dissolved reacts with the metallic salts in solution and the corresponding salts of the fatty acids are precipitated. This process continues until all the metals which form insoluble soaps are precipitated. The reaction which takes place is illustrated by that between sodium palmi-tate and calcium chloride —... 

Monovalent and polyvalent alkyl carboxylates are respectively called "soap" and "metallic soap." The straight chain of the fatty acids varies from C12 to C20. Higher members are too hydrophobic to be used and lower members have little surfactant value. Stearic acid soaps are doubtless the most widely utilized emulsifiers in oil-in-waier emulsions. Unsaturated fatty acid soaps such as oleate produce fluid emulsions (IS). The most common associated cations are sodium, calcium, magnesium, potassium, ammonium, and triethanolamine. Monovalent salts of carboxylic acids are generally used to produce oil-in-water emulsions. 

Ciasatication Sat. aliphatic carboxylic acid salt Definition Magnesium salt of stearic acid Empirical CjsHaMgO,... 

Metallic stearates, or soaps, are metal salts of organic acids like stearic acid. Calcium and zinc stearates are commonly used, although aluminum, iron, lead, lithium, magnesium, sodium, nickel, and potassium stearates are sometimes found in plastics. Stearates are most commonly used in thermoset polyester molding compounds, but calcium stearate has been used as a lubricant and release agent in polypropylene and ABS. Zinc and sodium stearates are used in polystyrene, SAN, and nylon. Stearates are not recommended for polycarbonate because of discoloration. Recommended loadings are usually 1 percent or less, but up to 5 percent has been used at times. 

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