Chemical Properties
Lithium stearate is a white powder. slightly soluble in water and ethanol, with a solubility of 0.09 g/100ml in water and 0.04 g/100ml in ethanol. insoluble in ethyl acetate and mineral oil. It forms colloids in mineral oil. It is decomposed into stearic acid and the corresponding lithium salt when encountering strong acid.
Uses
Lithium stearate is used as a thickener and gelling agent to prepare oils into lubricating greases. It is the active component of lithium grease. Further, it is used as lubricants, lubricant additives, plastic and rubber products. In addition to this, it is used as a stabilizing agent in the plastics industry.
Application
Lithium stearate is a lithium salt of stearic acid (LiC18H35O2) and is used as a processing aid or lubricant during filled elastomer part production. it is used as general purpose lubricating greases providing high resistance to water and the useful at both high and low temperature, which have found extensive applications in the automotive, aircraft and heavy machinery industry. Lithium stearate is the preferred lubricant because of its cleansing and scavenging action during sintering.
Preparation
Lithium Stearate is prepared by the reaction of lithium hydroxide with stearic acid (cooking tallow or other animal fat).
Synthesis Step: Dissolve 10 g of stearic acid in 100 mL of 95% ethanol, titrate with 0.5 mol/L lithium hydroxide ethanol solution, and use phenolphthalein as an indicator. After the reaction reaches the equivalence point, the precipitated lithium stearate soap is filtered out. The crude product can be recrystallized with 95% ethanol to obtain pure product.
Safety Profile
Low toxicity by
ingestion. Warning: This substance is
spontaneously combustible. When heated to
decomposition it emits toxic vapors of
lithum.
