Zinc Oxide
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Zinc Oxide is a chemical compound commonly used as a heat stabilizer, UV absorber, acid scavenger, and lubricant in producing PVC, polyolefins, and other polymers. It is a white, powdery substance made by heating zinc metal to a high temperature and oxidizing it with air.
As a heat stabilizer, Zinc Oxide helps to prevent the breakdown of polymers due to heat. This is important because polymers can break down when exposed to high temperatures, leading to discoloration, embrittlement, or even melting. By adding Zinc Oxide to the polymer formulation, the stability and durability of the polymer can be improved, ensuring that it can withstand these high temperatures without breaking down or degrading.
As a UV absorber, Zinc Oxide helps to protect polymers from the damaging effects of UV radiation from sunlight. This is important because UV radiation can cause polymers to degrade and become brittle, reducing their lifespan and performance. Adding zinc oxide to the polymer formulation can absorb UV radiation and prevent it from reaching the polymer.
As an acid scavenger, Zinc Oxide helps to neutralize any acidic compounds that may be present in the polymer formulation, or that may be produced during processing or storage. This is important because acidic compounds can react with the polymer and cause it to break down or degrade. Adding Zinc Oxide to the polymer formulation can neutralize any acidic compounds, preventing them from damaging the polymer.
As a lubricant, Zinc Oxide helps to improve the processing and handling of polymers during production. It acts as a mold release agent, preventing the polymer from sticking to the mold during shaping and forming. It also reduces friction between the polymer and the processing equipment, making it easier to extrude, inject, or blow mold the polymer into the desired shape.
In addition to PVC and polyolefins, Zinc Oxide is also used as a stabilizer and lubricant in the production of other polymers, such as polyurethanes, thermoplastic elastomers, and engineering plastics. It is often added to the polymer formulation in small amounts, typically between 0.1 and 5% by weight, to achieve the desired stabilizing and lubricating effects.