Lead stearate

Lead stearate

Names
Other names Lead(2+) octadecanoate, lead(II) stearate, lead distearate
Identifiers
CAS Number	1072-35-1 Y
3D model (JSmol)	Interactive image
ChemSpider	55198
ECHA InfoCard	100.012.733
EC Number	214-005-2
PubChem CID	61258
UNII	HQ5TZ3NAEI
CompTox Dashboard (EPA)	0029630
InChI InChI=1S/2C18H36O2.Pb/c2*1-2-3-4-5-6-7-8-9-10-11-12-13-14-15-16-17-18(19)20;/h2*2-17H2,1H3,(H,19,20);/q;;+2/p-2 Key: UQLDLKMNUJERMK-UHFFFAOYSA-L
SMILES CCCCCCCCCCCCCCCCCC(=O)[O-].CCCCCCCCCCCCCCCCCC(=O)[O-].[Pb+2]
Properties
Chemical formula	C 36H 70PbO 4
Molar mass	774.14
Appearance	White powder
Density	1.4 g/cm3
Melting point	115.7 °C (240.3 °F; 388.8 K)
Boiling point	359.4 °C (678.9 °F; 632.5 K)
Solubility in water	Slightly soluble
Hazards
GHS labelling:
Pictograms
Signal word	Danger
Hazard statements	H302, H332, H360, H373
Precautionary statements	P260, P261, P281, P304, P340, P405, P501
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa). Infobox references

Lead stearate is a metal-organic compound, a salt of lead and stearic acid with the chemical formula C
₃₆H
₇₀PbO
₄.^[1] The compound is classified as a metallic soap, i.e. a metal derivative of a fatty acid.^[2] The compound is toxic.

Synthesis

The compound can be prepared by reacting stearic acid, lead(II) oxide, and a catalyst acetic acid.^[3]

${\displaystyle \mathrm {2\ C_{17}H_{35}COOH+PbO\longrightarrow (C_{17}H_{35}COO)_{2}Pb+\ H_{2}O} }$

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

${\displaystyle {\mathsf {Pb(CH_{3}COO)_{2}+2NaC_{18}H_{35}O_{2}\ {\xrightarrow {}}\ Pb(C_{18}H_{35}O_{2})_{2}\downarrow +2CH_{3}COONa}}}$

Physical properties

White powder with a slight fatty odor. Sinks in water.^[4] Hygroscopic in air.

Slightly soluble in water.^[1] 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.^[5][6][7]

References