Stearic acid is white flakes, beads or blocks at room temperature. solid. It is composed of saturated fatty acids mainly C16 and C18. It is insoluble in water, slightly soluble in benzene and carbon disulfide, easily soluble in hot ethanol, non-toxic and tasteless, and has the general chemical properties of organic carboxylic acids.
Stearic acid is a fatty acid widely found in nature. Almost all oils contain stearic acid in varying amounts. The content in animal fats is relatively high. For example, the content in butter can reach 24%. %, the content in vegetable oil is less, tea oil is 0.8%, palm oil is 6%, but the content in cocoa butter is as high as 34%. There are two main production methods for industrial stearic acid: fractionation method and pressing method. A decomposing agent is added to the hardened oil, and then it is hydrolyzed to obtain crude fatty acids, which are then washed, distilled, and decolorized to obtain the finished product, while glycerol is produced as a by-product.
The role and precautions of stearic acid in filled modified masterbatch:
Stearic acid has become the lubricant, Plasticizing and stabilizing functional additive.
Stearic acid can effectively improve the activation effect of inorganic powder coating and increase the fluidity of materials. For materials where inorganic powder accounts for an absolute proportion, when the melt flow rate is required to be large, stearic acid should be appropriately increased. The acid content can significantly increase the melt flow of plastic materials.
However, the amount of stearic acid used in filled modified masterbatch has a limit, and is generally controlled at about 1% of the total mass. Excessive addition will cause the quality and performance of plastic products to decline, and will also cause sticky lakes to appear on mechanical devices such as the mold lip position of plastic product production equipment, affecting production efficiency and product quality.