Applications of Lanthanum Stearate

Applications of Lanthanum Stearate

1.Polymer Materials Field

Lanthanum stearate is a core component of high-performance rare earth heat stabilizers and is widely used in polymer materials such as polyvinyl chloride (PVC), polypropylene (PP), and polyethylene (PE).

• PVC Heat Stabilizer: During PVC processing, lanthanum stearate inhibits degradation by capturing hydrogen chloride (HCl) and replacing allyl chloride, significantly improving the heat resistance and weather resistance of the material. Compared with traditional lead salt and cadmium salt stabilizers, it is non-toxic, free of heavy metal pollution, meets environmental protection standards, and is suitable for fields such as food packaging and medical pipes. For example, in the production of medical infusion tubes, lanthanum stearate can ensure that PVC does not decompose during high-temperature sterilization and avoid the risk of heavy metal migration.

• Polymer Processing Aid: Its long-chain fatty acid structure endows the material with good lubricity, which can reduce the melt viscosity of the polymer, improve processing fluidity, and reduce mold wear during extrusion. In the production of PP/PE films, adding lanthanum stearate can improve the surface finish and anti-adhesion of the film, while enhancing mechanical properties (such as tensile strength and elongation at break).

2.Lubricating Oils, Greases and Metal Processing

As a lubricating additive, lanthanum stearate can improve the load-carrying capacity and anti-wear performance of lubricating oils.

• Lubricating Oil Additive: The rare earth metal ions in its molecular structure cooperate with fatty acid chains to form adsorption films and reaction films on the metal surface, reducing direct contact between friction pairs. When used in automobile engine oils and industrial gear oils, it can reduce the wear rate and extend the oil change cycle. For example, in the gear lubrication of heavy-duty machinery, lanthanum stearate can reduce the friction coefficient by more than 30%, significantly improving the operating efficiency of the equipment.

• Metal Cutting Fluid: As a component of water-based or oil-based cutting fluids, lanthanum stearate can enhance wettability and extreme pressure performance, reduce frictional heat between tools and workpieces, improve processing accuracy and tool life, and is suitable for cutting and grinding processes of difficult-to-process materials such as aluminum alloys and stainless steels.

3.Ceramics and Composite Materials

Lanthanum stearate plays a key role in ceramic preparation and composite material modification.

• Ceramic Dispersant: In the hydrothermal synthesis or sol-gel method of nano-ceramic powders (such as Al₂O₃, ZrO₂), lanthanum stearate acts as a surfactant to prevent particle agglomeration through electrostatic repulsion and steric hindrance effects, improving powder dispersibility and uniformity. For example, in the preparation of high-performance electronic ceramics (such as PTC thermistors), uniformly dispersed powders can ensure the stability of ceramic density and dielectric properties.

• Composite Material Reinforcer: When compounded with reinforcing bodies such as carbon fibers and glass fibers, lanthanum stearate can improve the interface compatibility between the polymer matrix and the reinforcing body. In epoxy resin-based composites, its rare earth metal ions form coordination bonds with polar groups in the matrix, improving the interface bonding strength, so that the flexural strength and impact toughness of the composite material are increased by 20%-30%.

4.Environmental Protection and Flame Retardant Field

Lanthanum stearate has both flame retardant and smoke suppression functions, and has significant application potential in environmentally friendly materials.

• Halogen-Free Flame Retardant: In materials such as polyurethane (PU) and unsaturated polyester (UP), lanthanum stearate delays combustion by catalyzing char formation and inhibiting the release of flammable gases. When it is used in synergistic flame retardancy with magnesium hydroxide, aluminum hydroxide, etc., it can reduce the amount of flame retardant added, avoid the deterioration of the mechanical properties of the material, and is suitable for scenarios such as building insulation materials and electronic and electrical enclosures.

• Wastewater Treatment: As a precursor of rare earth flocculants, the lanthanide hydroxide colloid generated by the hydrolysis of lanthanum stearate can adsorb heavy metal ions (such as Pb²⁺, Cd²⁺) and organic pollutants in water. Its flocculation efficiency is better than that of traditional aluminum salts and iron salts, and the amount of sludge produced is small, which is convenient for subsequent treatment.

5.Other Applications

• Agricultural Chemicals: Lanthanum stearate can be used as a micro-fertilizer additive. By utilizing the regulating effect of rare earth elements on plant growth, it can enhance the stress resistance of crops (such as drought resistance, disease and insect pest resistance) and improve fruit quality. Adding a small amount of lanthanum stearate to foliar fertilizers or slow-release fertilizers can improve nutrient absorption efficiency and promote crop yield increase.