Application of polyethylene wax emulsion in metal molding

Polyethylene wax emulsion metal die casting release agent is an interfacial coating used on the surface of two objects that are easily adhered to each other, it can make the surface of the object easy to detach, smooth and clean. Metal die-casting release agent is mainly used in various die-casting operations of aluminum alloy, magnesium alloy, zinc alloy and other metal materials.

The degassing agent (degassing agent) is when the powder coating is melted and leveled to form a film, the air, moisture contained in the powder coating and the volatile substances such as small molecule compounds produced during the crosslinking and curing reaction of the powder coating escape. And make it The pinholes that escaped the small molecule compounds can be closed in time to prevent the coating film from producing small pinholes or pig pores and other additives for drunkenness. This additive is one of the most commonly used additives in powder coatings. All powder coating formula towels must be painted.

The degassing agent commonly used in powder coatings is benzoin, also known as diphenylethanol (commonly known as benzoin). Benzoin is a white or light yellow odorless body with a melting point of 133~137°C and a point of 344°C. It is slightly soluble in water and Ethyl ether, soluble in hot lactone and ethanol; its disadvantage is that it causes yellowing of the coating film at high temperature, in order to take the shortcomings of benzoin, modified benzoin and wax type that are not easy to change color under baking conditions have been developed. The degassing agent.

In the powder coating towel with benzoin, the bubble shrinkage is very fast when the powder coating is melted and leveled, the coating degree has not changed, and almost all the bubbles disappear: the bubble shrinkage is very slow when the surface is not added with benzoin. The degassing mechanism of benzoin is that benzoin consumes the oxygen in the bubbles and reduces the bubble diameter. From the south, the internal sheet force of the bubble increases, which speeds up the solubility and selection of nitrogen in the polymer, and reduces the bubble diameter from the surface. Benzoin begins to vaporize at 120°C, which is another important aspect of benzoin’s degassing effect. The results of experiments and production practices show that in the cross-linking and curing process of powder coatings, coatings that produce small molecular compounds must be added with degassing agents. . Generally, it is better to add a degassing agent in epoxy, epoxy-polyester, polyester and polyurethane powder coatings. This is because the powder coatings still have problems such as easy moisture absorption during the production and use process. Oxygen matt and semi-gloss powder coating towels are not easy to produce pig pores without deaerators such as benzoin. The reason cannot be explained clearly. It may also be that the surface of the coating film is not as high-gloss and smooth, and some coating films are lacking. Obviously generated feeling.