The Role of Lubricants in Plastic Processing: In the field of plastic processing, lubricants play a crucial role. They significantly improve processing flowability, reduce energy consumption, prevent melt adhesion to equipment, and enhance the surface finish of the final product. Based on their mechanism of action, lubricants are primarily categorized into two main types: Internal Lubricants: These exhibit a certain degree of compatibility with the polymer resin, allowing them to penetrate between the polymer molecular chains and reduce internal friction between the chains. Functioning similarly to adding oil inside a chain, this enables molecular chains to slide past each other more easily, resulting in: reduced melt viscosity, improved flow, lower processing torque and energy consumption, and promoted plastification (especially critical for PVExternal Lubricants: These have poorer compatibility with the polymer resin and tend to migrate to the melt surface, forming a lubricating film between the melt and processing equipment (screw, barrel, mold). Analogous to oiling a metal contact surface, their main functions are: preventing melt adhesion to equipment surfaces, reducing friction between the melt and metal equipment surfaces, facilitating demolding, and improving the surface gloss of the final product while reducing defects.
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