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The second in a two‐part series, describes various applications of calcium stearate in resins and resinous polymers. Focuses in particular on its use in polypropylenes and stynenes (e.g. as a slip agent, a dispersing agent, a light stabilizer, or a nucleating agent) and in polyvinyl chlorides (e.g. as a pure‐proofing agent, to enhance ageing and heat resistance or as a non‐toxic stabilizer against acid, heat and light). Also considers the different applications of various stearate blends.

Calcium stearate has been incorporated into carbon paper (7683), e.g. as a filler (7684), and in paper coatings (7685). It can act as a lubricant, leveller, and plasticizer in paper coatings (7686), and gives improved anti‐dust and gloss properties in calendering (7687), and enhanced flow and levelling (7688). Along with ammonium stearate the calcium soap has been used as a lubricant in paper coatings to improve tear strength and gloss (7689), and wet strength. Paper and paperboard have been coated with equal parts of calcium stearate and acrylic/styrene copolymers to increase water resistance (7690). Particles of aluminium hydroxide have been coated with calcium stearate and with stearic acid to give the material hydrophobic properties, resistant to exposure to boiling water and solvents, and useable as a filler in paper (and plastics) (7691). Ketene dimers along with calcium stearate have been used in paper sizing (7692), and the stearate alone has been used to make water resistant abrasive papers (7693), and also, at a concentration of 2/3%, has been employed to render cardboard resistant to water steeping and swelling (7694). Stable dispersions of the stearate soap have been utilized in the surface treatment of computer cards (7695). Titanium dioxide coated with calcium stearate has been included in polyethylene coating compositions for photographic paper supports (7696). Release paper for adhesive lables have contained calcium stearate, to give improved workability on automatic labelling machines (7697).

This paper aims to investigate the influence of stearate types on the thickening ability, dropping point and fiber structure of greases.

Several greases were prepared from polyolefins and various stearates. The melting point of the stearates and the dropping point of the resultant greases were measured, and the intermolecular binding energies of the thickener and the radial distribution function of the metal–oxygen in the thickener were determined with the aid of molecular simulation. The microstructures of the greases were also analyzed via scanning electron microscopy.

A higher stearate binding energy was found to correlate to a higher dropping point of the resultant greases. The thickening ability of the stearate is related to the group and period of the constituent metal ion. Within a group, greater atomic numbers of the metal were correlated to lower thickening ability. In a period, as the atomic number of the metal increased, the thickening ability was enhanced. The radial distribution functions of metal and oxygen can explain the aggregation of the stearate thickeners in the grease.

This work compared the thickening capacity of several stearates. Guidelines for preparing stearates to tailor the resultant grease are presented.

Zinc stearate (Zinc distearate) is a fine white soft and muctuous odourless bulky powder, molecular weight 632. Its outstanding characteristic is the extremely small particle size of the top quality material, which can be less than one micron in diameter, giving it a high specific surface e.g. the order of 25,000 sq.cm. per gram.

Aluminium stearate is a fine, bulky, odourless and colourless powder forming a plastic mass when heated, having the properties both of organic and inorganic matter. It embraces most of the characteristics of other metallic stearates and is regarded as the most important of these. Several studies of the material have already appeared in past years.

Calcium stearate has many uses, including that of a flatting agent in paint, a lubricant, plasticizer and leveller for paper coatings, suspending agent in plastic and other mouldings, a tableting agent, a water repellant, and a cosmetic component, etc. Gives a complete breakdown and analysis of calcium stearate with a useful Appendix of journal and patent specification.

Calcium stearate has been applied to the production of gels with paraffin oil for use in cosmetic formulations (7554), and it can be employed to improve the processing and performance of loose powders and compacted powders. It is useable in body powders, and can function as a coating material for titanium dioxide that is to be used in cosmetics (7555).

Magnesium stearate (Mg (C12H33O2)2) is a fine white odourless bulky powder, probably the finest of the metallic stearates, with a very high covering capacity. It has rounder particle shape than does, say, zinc stearate and is a muctuous soapy powder adherent to the skin, and is rated as dermatologically innocuous being neither a sensitizer nor a primary irritant. It can be decomposed by acids, and can exist as the hydrate. Its physical characteristics have been examined closely.

A general review of the manufacture, properties, and uses of calcium stearate appeared in 1984. Its uses include that of a flating agent in paint, a lubricant, plasticizer and leveler for paper coatings, suspending agent in paints, a release agent in plastic and other mouldings, a tabletting agent, a water repellant, and a cosmetic component, etc. Methods for the production of the stearate have been published, e.g. from calcium hydroxide, in the presence of zeolites, as dust free granules, in spherical particles (for use as a stabilizer in poly (vinyl chloride), and as an aqueous surfactant, viscosity stabilized dispersion. The drying of the soap has also been described. Calcium/zinc stearate binary mixtures have been prepared, and calcium stearate dihydrate.

A number of oleochemicals have found application in the formulation of metal processing lubricants. Calcium palmitate can act as a gelling inhibitor for lubricants for non‐chip metal forming, and diglyceryl oleate and sodium oleyl sulphate have been employed in chipless forming and machining lubricants. Glyceryl monooleate has been used together with paraffin wax and xylene for forming aluminium sheets, and isopropyl oleate has been blended into lubricants for cold forming of metal. Lubrication in cold forming of steel and aluminium alloys has been promoted by the use of sodium stearate and phosphating processes. Stearic acid has also been utlized in metal forming. Butyl butanamine stearamide is applicable in lubricants for non‐ferrous metal working, and coatings that can prevent galling when titanium is cold worked can be formed on the metal by the use of 0.5 grams of hydrofluoric acid, with 10 grams stearic acid in 100 ml. of a solvent, the process being accelerated by the inclusion of phosphoric acid at 0.85 grams. Calcium stearate has also been used in solvent‐based metalworking Iubricants, in acrylic electrophoretic lubricant coatings on metal, and in bentonite‐containing metalworking oils. Mixtures of cetyl alcohol and tricresyl phosphate have been cast into slabs and used on metalworking tools.