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Oxidized polyethylene wax serves as a highly important and efficient external lubricant and processing aid in PVC manufacturing. It plays an irreplaceable role by enhancing processing fluidity and improving the surface quality of finished products.
1. Superior External Lubrication Effect
Mechanism: The molecular chains of oxidized polyethylene wax carry polar groups such as carboxyl and hydroxyl groups. These groups enable one end to weakly anchor onto PVC molecular chains, while the long-chain alkane groups at the other end extend outward.
Effect: This creates an effective lubricating film between the PVC melt and the metal surfaces of processing equipment (e.g., barrels, screws, molds). This film significantly reduces friction between the melt and metal surfaces, preventing melt adhesion to equipment. Consequently, material is easier to convey, plasticize, and demold.
2. Promoting Plasticization and Improving Flowability
Although primarily functioning as an external lubricant, its moderate polarity provides slight compatibility with PVC, preventing complete “slippage” unlike paraffin wax. It reduces friction-induced heat while ensuring effective shear force transfer, aiding uniform plasticization of PVC resin. This lowers melt viscosity and enhances flowability.
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