thermoplastic compression molding

Compression molding is a very effective technique for manufacturing thermoplastic composites. Thermoplastic compression molding techniques include the processing of long fiber reinforced thermoplastics (LFT) and glass mat reinforced thermoplastics (GMT). If you want to know more about compression molding of thermoplastics, please read on.

What are thermoplastics?

Thermoplastics refer to plastics that have the ability to be heated to soften and cooled to harden many times over. Most of the plastics we use in our daily life belong to this category.

Polyethylene, polypropylene, polyvinyl chloride, polystyrene, polyformaldehyde, polycarbonate, polyamide, acrylate plastics, other polyolefins and their copolymers, polysulfone, polyphenylene ether, chlorinated polyether, etc. are all thermoplastics.

In thermoplastics, the resin molecular chains are linear or branched structures, which are gathered by the physical attraction of subvalent bonding forces. After being subjected to heat and pressure, the subvalent bonding force gradually disappears and the resin starts to melt. As the temperature increases, its viscosity gradually decreases and becomes a viscous flow state. When the external force is applied, the melt can be easily deformed or flowed to fill all parts of the mold cavity and can be shaped into products after cooling. The whole process is a physical change. Unlike thermoset molding, this change is reversible and can be repeated.

What is the compression molding process of thermoplastics?

The process of thermoplastic molding can be simplified as follows: heating - filled mold - cooling - forming - demolding.

The preparation process involves laminating raw materials, heating, pressure impregnation, cooling and shaping, and cutting to make sheets, which are then molded into the desired parts. You can also use granular plastic raw materials directly. This molding process requires a mold that is preheated to 60 to 200 degrees Celsius, depending on the plastic being used. Once the mold is heated, it is filled with powdered thermoplastic and compressed between two molds. This compression forces the material into the mold cavity and allows it to cool into its final shape.

Thermoplastics can be used in the automotive manufacturing industry for sub-structural parts, such as door panels, seats, top covers, bumpers, fenders, hoods, dashboards, floorboards, shelves, etc. In the construction industry, it can be used for manufacturing countertop, sanitary ware, door panel, water tank, etc.. It is also used in the chemical anti-corrosion and food industries.

MDC has used compression molded thermoplastic parts in industries such as aerospace, automotive and defense. If you are considering creating thermoplastic parts with complex designs and geometries, you can choose the most professional compression mold manufacturer in China.