Aluminium stearates

Aluminium stearates are produced by the precipitation process only. There are three possible combinations of aluminium with fatty acids: The ratio of aluminium to fatty acid does not necessarily correspond to the stoichiometric values. Any ratio is possible between the extremes 1:1 and 1:3. Therefore there are many varieties of aluminium stearates, generically referred to as aluminium mono-, di- or tri-stearate, whose properties differ from one another in respect to physical properties such as melting point, free fatty acid and particularly the gelling properties. Oils with a low viscosity are best thickened by aluminium tri- and di-stearates, whilst very viscous oils form stiffer gel when combined with aluminium di- or mono-stearates. The dropping point of aluminium greases usually range from 110 °C to 120 °C, but we are in a position to offer special stearates whose dropping point exceed 200 °C. All aluminium greases are highly hydrophobic and are characterised by outstanding transparency and good adhesion to metallic surfaces. Due to their excellent water repellency, aluminium stearates are used in coatings and building industry materials as water repellent ingredients. Aluminium mono-, di- and tri-stearates are insoluble in water, lower alcohols, esters and ketones. In benzenes, aromatic compounds and halogenated hydrocarbons as well as in natural and mineral oils, they dissolve to a gel when heated.