Aluminum Stearate V.S Calcium Stearate
The chemical is insoluble in water and remain stable under various extreme as well as ordinary conditions. It is and inorganic chemical with a molecular formula (C17H35COO)3Al and is appreciated for the features such as high efficiency, purity and chemical compositions.
Aluminium Stearate is a white coloured powder. It is the aluminium salt of stearic acid. It is insoluble in water, alcohol and ether. However, it is soluble in glycol, alkali, BTX, chlorinated hyrdocarbons. It dissolves well in vegetable oils on heating and if high concentration is used, on cooling gelling is seen.
Aluminium Stearate is used as an emulsifier in cosmetics. It is also used as lubricant in polyamides and in thermosetting of plastics. Its use as a water repellent agent and hydrophobic agent makes it useful to be used as a waterproofing agent in paint industry.
Aluminium stearate is used as thickening agent in production of varnishes and lacquers. It also finds use as an anticaking agent in petroleum products.
Due to high reactivity, calcium oxide is handled, stored and packaged ensuring minimal atmospheric contact at our premises.
Calcium Stearate is an insoluble salt of calcium, stearic acid and palmatic acid. In hard water, when soap of calcium ions is mixed, the scum that is formed is calcium stearate. Calcium stearate is non-toxic and has many applications as stabilizer and lubricant.
Besides water, it is insoluble in water, ether, chloroform, acetone, cold alcohol as well.
However, it is slightly soluble when dissolved in hot alcohol, hot vegetable and mineral oil. It shows good solublity in hot pyridine.
The use of calcium stearate is seen widely as a stabilizer for PVC resins and lubricant for plastic moulding powders or tablets.
Its use is recommended also in emulsions, cements, pencils, construction chemicals, paint flattening agent, resin coated sands and foundry chemicals, decaking agent in food items like onions and cosmetics. Use of calcium stearate is seen as a lubricating agent in paper and paperboard coating compositions, iron wire drawing and leather cloth manufacturing as well.
Its use has been extended as a neutralizer, colour stabilizer, reducer of fiber breakage and de-agglomerator in PP and HDPE applications.
Calcium stearate is also known as octadecanoic acid calcium salt, stearic acid calcium salt.
GREASES, LUBRICATING OILS: ALUMINIUM STEARATE gives excellent properties of transparency, stringiness and water repellency. It acts as a high temperature resistant when added in lubricants. ALUMINIUM STEARATE is used by ONGC for defoaming properties.
DRY LUBRICATION : Useful as a lubricant in metals processing, such as wire drawing, producing brighter products.
PAINTS, VARNISHES AND LACQUERS : Adequate for improving pigments suspension, control of viscosity and gloss, water resistance and improving brushing and penetration.
It finds very wide application in paint industries for preparation of enamels and lacquers where it acts as thickening agent or suspending agent. It reduces sagging and setting of pigment and works as varnish drier. It is used as an important ingredient for water proofing in tarpaulin & textile industrie.
PRINTING INKS : The high gelling properties of ALUMINIUM STEARATE are useful for thickening and suspension improving
PLASTICS : It is used in as a lubricant in the production of Polyamides and Thermosetting plastics.
RUBBER : Used as dusting powders to prevent sticking of unvulcanised rubber sheet.
CONSTRUCTIONS : Recommended jointly with CALCIUM STEARATE for improving the water resistance of concrete and cements.
source: fanavaran chimi