Zinc Stearate
Zinc Distearate, ZnSt, Zinc Octadecanoate.
- CAS
- 557-05-1
- EC
- 209-151-9
- Sectors
- Plastics & Polymers, Rubber & Elastomers, Coatings, Adhesives, Sealants & Elastomers
Zinc Stearate (CAS 557-05-1) is a neutral zinc soap supplied as a white powder with a fatty acid odour, free of electrolytes, that ranks as the most powerful mold release agent among metallic stearates and serves as a PVC heat stabilizer and a vulcanization activator in rubber. This Technical Grade powder is characterized by its high clarity and lack of electrolytes, ensuring minimal impact on polymer transparency.
The product functions as an essential Heat Stabilizer in PVC processing, often used in synergistic blends to prevent degradation during extrusion. Its hydrophobic nature makes it an excellent sanding aid in wood coatings, preventing the clogging of abrasive surfaces.
With a low melting point compared to other stearates, it disperses rapidly in rubber and plastic melts, providing surface lubrication. It also acts as an activator for sulfur vulcanization in the rubber manufacturing industry.
Typical Properties
| Molecular formula | C18H36O2.1/2Zn |
|---|---|
| Molecular weight | 632.33 g/mol |
| Appearance | white powder with fatty acid odour |
| Form | Powder |
| Color | White |
| Odor | wh. powd., faint char. odor |
| Melting point | 130 °C |
| Boiling point | 240°C[at 101 325 Pa] |
| Density | 1.095 g/cm³ |
| Water solubility | Insoluble |
| Flash point | 180°C |
| GHS signal word | Warning · Irritant / harmful, Environmental hazard |
| HS code | 29157020 |
| Grades available | Technical Grade |
Typical literature values for identification; lot-specific results are stated on the certificate of analysis (COA) and the safety data sheet (SDS) that accompany every delivery.
Zinc Stearate
Applications
• Plastic Processing: Utilized as a Release Agent and lubricant in polystyrene, polyurethanes, and polyesters to ensure clean de-molding.
• Coatings & Lacquers: Employed as a Sanding Aid and flatting agent in wood finishes, allowing for smoother surfaces and easier processing.
• Rubber Compounding: Functions as an Internal Lubricant and vulcanization activator, improving the flow and curing speed of rubber batches.
Safety & Risks
Handle with care to avoid dust clouds; zinc oxide fumes can be released during high-heat decomposition. Wear Respiratory Protection and Chemical Resistant Gloves. Hazard Classifications: Aquatic Chronic 1 (H410).
Packaging
Available in 20 kg or 25 kg PE Bags and 500 kg FIBC Big Bags.