Basic information about calcium stearate

Calcium stearate is a white powder, insoluble in water, cold ethanol and ether, soluble in organic solvents such as hot benzene, benzene and turpentine, and slightly soluble in hot ethanol and ether. When heated to 400, it decomposes slowly, is flammable, decomposes into stearic acid and corresponding calcium salts in case of strong acid, and is hygroscopic.

　Second, the production method of calcium stearate

　2.1. Direct Law

　In the reaction pot equipped with agitator and thermometer, a quantitative stearic acid and cao are added, heated up to melting, and the catalyst h2o2 is slowly added under continuous stirring, and vacuum is pumped to control the reaction temperature at 140 ~ 150, the reaction 1.5 ~ 2.0h. After the reaction is completed, the product is discharged, cooled and crushed.

　2.2. Complex decomposition

　The stearic acid is dissolved in hot water of 20 times the mass, and the saturated caustic soda solution is added, and the saponification reaction is carried out at about 75 to form a dilute sodium stearate solution. Then the calcium chloride solution with a content of 1074kg/m3 was added to the sodium stearate solution, and the re-decomposition reaction was carried out at about 65, and the product calcium stearate was precipitated. Then filtered, washed, dried at about 90, that is, the finished product.

　Third, the lubrication effect in pvc formula

　Calcium stearate acts as a heat stabilizer for PVC and a lubricant and mold release agent for a variety of plastic processing. When used as a PVC lubricant, it is generally considered an internal lubricant. Calcium stearate is a stearate of medium strong alkali calcium, with strong polarity, the chemical activity point of PVC resin particles can form a relatively stable complex system with calcium stearate. The two long-chain alkyl groups of calcium stearate have less compatibility with polar resins such as PVC, and constitute a local microscopic two-phase interface inside the PVC resin, that is, a lubrication film. The microscopic nature of its lubrication is that the local lubrication interface formed by the non-polar long chain alkyl group and the force between the polar resin chain segments is less than the force between the resin chain segments, and because there are many small pores between the resin segments, when the resin chain segments are displaced, the alkyl groups that can be arbitrarily deformed are squeezed into other pores adjacent to them, thereby reducing the resistance during the displacement of the resin chain segments and playing an internal lubrication role.

　In practical application, calcium stearate as pvc lubricant not only plays an internal lubrication role, its lubrication effect is more complex, in other cases where the proportion of internal lubrication is relatively high, it will reflect the role of external lubrication. Moreover, it has a synergistic effect with many lubricants.

Calcium stearate (Xeno)

　In hard products, the combination with salt-based lead salts and lead soaps can improve the gelatinization speed. It is also used in food packaging, medical equipment and other soft films and appliances that require non-toxicity. It can be used as a halogen absorber for PE and pp to eliminate the adverse effects of residual catalysts on color and stability. Used as a plasticizer in rubber processing, it can soften natural rubber and synthetic rubber without almost no effect on vulcanization. It is also used as a lubricant for polyolefin fibers and molding compounds, a thickener for greases, a water repellent for textiles, a plainening agent for paints, a plasticizer for the manufacture of plastic records, a lubricant and release agent for thermosetting plastics such as phenolic and amino, a lubricant for pencil refills, and a food-grade calcium stearate as an anti-caking agent.

　The use of calcium stearate alone in the formula can accelerate plasticization, improve melt viscosity, increase torque, and have a certain release effect, while the use of paraffin wax alone shows delayed plasticization, reduced torque, and no release effect. When calcium stearate and paraffin (polyethylene wax) are mixed in a certain proportion, it shows a good effect, and the torque value of the material can be reduced a lot, which is due to the infiltration of paraffin into the calcium stearate molecules, strengthening the lubrication effect, showing a strong synergistic effect, changing the dispersion of the lubricant. Other applications

　　Sainuo New Material, 15 years of accumulation, polyethylene wax brand manufacturer, Blue Ocean equity institution listed enterprises. Focus on the research and development and production of lubrication and dispersion systems, including polyethylene wax, oxidized polyethylene wax, polypropylene wax, ebs, zinc stearate and other additives research and development, production and application work. Hotline: [phone].