Stearic acid, or octadecanoic acid, molecular formula C18H36O2, is produced by hydrolysis of fats and oils and is mainly used in the production of stearates. Each gram is dissolved in 21ml ethanol, 5ml benzene, 2ml chloroform or 6ml carbon tetrachloride. It is white waxy transparent solid or slightly yellow waxy solid, can be dispersed into powder, slightly with butter odour. At present, the vast majority of domestic production of stearic acid enterprises are imported from abroad palm oil, hydrogenation into hardened oil, and then hydrolysis distillation to make stearic acid.
Stearic acid is widely used in cosmetics, plastic plasticizers, mold release agents, stabilizers, surfactants, rubber vulcanisation accelerators, water repellents, polishing agents, metal soaps, metal mineral flotation agents, softeners, pharmaceuticals and other organic chemicals. Stearic acid can also be used as a solvent for oil-soluble pigments, a crayon sliding agent, a wax paper polishing agent, and an emulsifier for glycerol stearate. Stearic acid is also widely used in the manufacture of PVC plastic pipes, plates, profiles and films, and is a heat stabiliser for PVC with good lubricity and good light and heat stabilisation.
Mono- or polyol esters of stearic acid can be used as cosmetics, non-ionic surfactants, plasticisers and so on. Its alkali metal salt is soluble in water and is one of the main components of soap, while other metal salts can be used as water repellents, lubricants, fungicides, paint additives and PVC stabilisers.
The role of stearic acid in polymeric materials is demonstrated by its ability to enhance thermal stability. Polymer materials are prone to degradation and oxidation during high temperature processing, leading to a decline in performance. The addition of stearic acid can effectively slow down this degradation process and reduce the breakage of molecular chains, thus extending the service life of the material. This is particularly important in the manufacture of high-temperature resistant products such as wire insulation and automotive components.
Stearic acid has excellent lubricating properties as a lubricant. In polymer materials, stearic acid reduces friction between molecular chains, allowing the material to flow more easily, thus improving the efficiency of the process. This is very beneficial for production processes such as injection moulding, extrusion and calendering.
Stearic acid exhibits a plasticiser effect in polymeric materials, increasing the softness and malleability of the material. This makes the material easier to mould into a variety of shapes, including films, tubes and profiles. The plasticising effect of stearic acid is often applied in the production of plastic packaging, plastic bags and plastic containers.
Polymeric materials are often prone to water absorption, which can degrade their properties and cause corrosion. The addition of stearic acid improves the water repellency of the material, allowing it to remain stable in wet environments. This is of key importance in areas such as outdoor products, construction materials and electronic device housings.
Stearic acid helps to reduce the colour change of polymeric materials in UV and thermal environments. This is important in the manufacture of colour stable products such as outdoor billboards, automotive interior parts and outdoor furniture.
Stearic acid acts as an anti-adhesive and flow aid in polymeric materials. It reduces adhesion between molecules and makes the material flow more easily, especially during the injection moulding process. This improves productivity and reduces defects in the product.
Stearic acid is used as an anti-caking agent in compound fertiliser manufacturing to ensure uniform dispersion of fertiliser particles. This helps to improve the quality and uniformity of the fertiliser and ensures that plants receive the proper nutrients.
Stearic acid is used in a wide variety of industrial and consumer applications.
Post time: Jun-05-2024
