The role of Mold Release Agent Plastics will produce two kinds of friction during injection molding. One is the internal friction between polymer molecules when the polymer is heated and melted, and the other is the external friction between the polymer melt and the surface of the processing mold. force.
Due to friction, the fluidity of the melt is easily reduced, resulting in unfavorable results, such as poor processing performance, slow processing speed, products not easily filled with molds with complex shapes, the rough surface of products, lack of gloss, and wrinkles in severe cases. One of the effective ways to overcome the above two kinds of friction is to add lubricant. What we call a release agent is actually an external lubricant. It can be added to the mixture during use, or it can be painted on the surface of the mold. When the release agent is applied externally, the release agent forms a smooth and dense film on the surface of the mold to isolate the mold from the processed material. This release agent film must be able to bond well with the mold surface, not easily detached and damaged, but not have any reaction or adhesion with the product, and can well peel off the molded product.
In the demolding process, the mold release agent can be precipitated from the inside and evenly distributed on the surface of the plastic product, forming a layer of lubricant film or vapor between the mold and the plastic product. Typical materials that can be used as internal release agents are metal soaps and stearates, oleic acid, organic phosphites, silicone oils, and waxes. Comparing the external mold release agent and the internally added mold release agent, you will find that the internally added mold release agent has a better effect, which can eliminate the steps required for external mold release agent coating, and at the same time, it can also eliminate the Any possibility of damage to the mold caused by improper use.