Aluminum Stearate is a chemical compound that is known as a key additive in many industries. It is the result of the reaction between stearic acid (a natural fatty acid) and aluminum salts, and its chemical formula is Al(C18H35O2)3. This compound is produced as a white, soft, and light powder and is insoluble in water. Despite these characteristics, it has many applications in various industries, including the polymer, paint, cosmetic, pharmaceutical, and even electronics industries.
Physical and chemical properties:
Aluminum stearate is a heat-stable material and has high resistance to many solvents. However, it reacts with hot mineral acids such as sulfuric acid or nitric acid and decomposes into stearic acid and aluminum salts. Its chemical stability, good dispersibility, high hydrophobicity and lubricating properties make it very suitable for various applications.
Application in the plastic and polymer industries:
In the polymer industry, aluminum stearate is used as an internal and external lubricant for polyethylene, polypropylene, PVC and other thermoplastics. This material reduces friction between the polymer and the mold walls during extrusion or injection. It also plays a role as a thermal stabilizer, especially in processes where the polymer is exposed to high temperatures. On the other hand, its halogen-absorbing property removes catalyst residues from the resin and increases the final product quality.
Role in the rubber industry:
In the production of rubber parts and the molding process, aluminum stearate is used as a mold release agent. This property helps prevent the product from sticking to the mold and facilitates the removal of parts from the mold. It also acts as a lubricant and dispersant for fillers in rubber compounds.
Use in paints, inks and coatings:
Another important application of this material is in the coating industries such as industrial and construction paints. Aluminum stearate, with its hydrophobic properties, is used in the formulation of paints that require resistance to moisture. This material increases the durability of the paint and prevents the absorption of moisture on painted surfaces. Also, due to its stability against light and heat, it ensures better durability of the paint on metal, wood and plastic surfaces.
Role in the cosmetics and health industries:
In the formulation of cosmetic products, aluminum stearate has several roles. This material is used as an emulsifier, thickener, lubricant and stabilizer in creams, lotions, pancakes, eye shadows, blushes and various cream-powders. It also prevents the clumping of materials, increases the uniformity of pigment distribution and increases the final quality of the products. Another of its benefits in cosmetic products is that it creates a soft and silky feel on the skin.
Application in the pharmaceutical industry:
In the pharmaceutical industry, aluminum stearate is usually used as a lubricant in the tablet production process. This substance prevents the tablet from sticking to molds and equipment by creating a thin layer on the surface. It is also used in some cases as a coating material to prevent the tablets from getting wet. Since this substance is safe in low doses, its use in edible products is approved by pharmaceutical standard organizations.
Role in the formulation of lubricants and greases:
In the production of industrial lubricants and greases, aluminum stearate is used as a thickener and structural stabilizer. This substance provides physical stability to the grease against temperature, mechanical shear and oxidation. Its low moisture absorption also prevents the lubricant from becoming unstable or changing viscosity under different environmental conditions.
Safety and Environmental Considerations:
Aluminum stearate is considered non-toxic when used in controlled amounts and has been approved by safety agencies such as the FDA for some pharmaceutical and cosmetic applications. However, continuous inhalation of its powder in industrial environments can cause respiratory irritation, so the use of a mask and proper ventilation in work environments is recommended.
Aluminum stearate is one of the most widely used additives in various industries due to its unique properties such as lubricity, hydrophobicity, thermal stability, emulsification and anti-sticking. From polymer and paint production to pharmaceutical and cosmetic industries, this material plays a vital role in improving the quality and production process. The future use of this compound will grow due to the increasing demand for high-performance and safer products.
For more technical information, to receive a safety data sheet (SDS), or to purchase aluminum stearate in bulk, contact our experts.
Read more: