What is sodium stearate?

📌 Product Overview

Sodium stearate (CAS: 822-16-2) is a sodium salt of a long-chain fatty acid (molecular formula C₁₈H₅₃NaO₂), appearing as a white powder with a fatty odour and a slippery texture. As a core component of soap bases, its aqueous solution is weakly alkaline, easily soluble in hot water or hot ethanol, and decomposes upon contact with acids. It is widely used in the cosmetics, plastics, and metal processing industries.

⚖️Key Specifications and Parameters 

Industrial Grade Standards: 

Purity: ≥99.5% (non-aqueous titration method) 

Loss on drying: ≤5.0% (105°C constant weight method) 

Free acid (stearic acid): ≤3.0% (acid-base titration) 

Particle size: 200 mesh pass rate ≥99% (sieve analysis method)

Melting Point: 245–255°C (DSC analysis)

🧪 Core Application Scenarios

Personal care products:

✅ Soap/detergent: Main ingredient (accounting for 30-70% of the formula), providing foam control and cleaning power;

✅ Cosmetics: Emulsifier in shaving gel/lotion (usage 1-5%);

✅ Toothpaste: Thickening and curing agents (addition rate ≤3%). 

Plastics and Rubber: 

✅ Heat stabilisers: Used in polyethylene/polypropylene (addition rate 0.5-2%); 

✅ Lubricating release agents: Enhance the release efficiency of phenolic resins. 

Industrial Additives: 

✅ Metal processing: Corrosion inhibitors for cutting fluids;

✅ Waterproofing materials: Hydrophobic components for cement/textiles.

📦 Packaging and Storage

Packaging Specifications:

Industrial Grade: 25kg/bag (woven bag + polyethylene lining);

Storage Requirements:

✅ Cool, dry environment (humidity <60%), away from acidic substances;

✅ Reagent grade requires refrigeration (2-8°C), industrial grade can be stored at room temperature for up to 2 years.