Lead stearate is a metal-organic compound, a salt of lead and stearic acid with the chemical formula C36H70PbO4. The compound is classified as a metallic soap, i.e. a metal derivative of a fatty acid. The compound is toxic.

Synthesis

The compound can be prepared by reacting stearic acid, lead(II) oxide, and a catalyst acetic acid.

2 C 17 H 35 C O O H + P b O ⟶ ( C 17 H 35 C O O ) 2 P b + H 2 O {\displaystyle \mathrm {2\ C_{17}H_{35}COOH+PbO\longrightarrow (C_{17}H_{35}COO)_{2}Pb+\ H_{2}O} }

Also, an exchange reaction between lead(II) acetate and sodium stearate:

P b ( C H 3 C O O ) 2 + 2 N a C 18 H 35 O 2 → P b ( C 18 H 35 O 2 ) 2 ↓ + 2 C H 3 C O O N a {\displaystyle {\mathsf {Pb(CH_{3}COO)_{2}+2NaC_{18}H_{35}O_{2}\ {\xrightarrow {}}\ Pb(C_{18}H_{35}O_{2})_{2}\downarrow +2CH_{3}COONa}}}

Physical properties

White powder with a slight fatty odor. Sinks in water. Hygroscopic in air.

Slightly soluble in water. Soluble in hot ethanol.

Uses

The compound is used as a drier in oil paints and varnishes to speed the polymerization and oxidation processes. Also used as a lubricant and stabilizer in vinyl polymers and as a corrosion inhibitor in petroleum products.