Zinc Stearate-Release Agent and Stabilizer for Plastics and Coatings

Zinc Stearate (CAS 557-05-1): Properties

Zinc stearate is a widely used zinc salt of a fatty acid. A light powder or white granules without a pungent odor. It serves as a universal release agent in manufacturing, and also as a stabilizer and water-repellent additive in paints, varnishes, and cosmetic products.

1. Chemical Structure

Zinc stearate is formed by the neutralization of stearic acid (C₁₇H₃₅COOH) with zinc ions (Zn²⁺). The result is an organometallic salt with a long hydrocarbon chain that imparts hydrophobic properties to the substance.

2. Properties

Formula: Zn(C₁₇H₃₅COO)₂

Appearance: Fine white powder

Density: ~1.10 g/cm³

Decomposition: Occurs upon strong heating with the release of smoke and ZnO

Solubility: Insoluble in water; moderately soluble in hot organic solvents

3. Main Areas of Use

Plastics: In the production of PVC and polyolefins to improve processing and thermal stability.

Coatings and paints: Dispersing agent, water resistance, and coating protection.

Cosmetics: Dry deodorants, powders, skin care products, creating a barrier effect.

4. Safety and Limitations

Hygienic aspects: Avoid inhalation of dust; use filtering masks.

Flammability: Not combustible in pure form, but the organic part may ignite at very high temperatures.

Environmental aspects: Zn²⁺ compounds require control within permissible limits.

5. Conclusion

Zinc stearate (CAS 557-05-1) is a multifunctional ingredient that improves the technological characteristics of polymers, paint compositions, and cosmetic products. The optimal combination of hydrophobicity and thermal stability makes it one of the key organometallic agents in modern chemical production.