2-(2H-Benzotriazol-2-yl)-4,6-di-tert-pentylphenol (UV-328) is a high-efficiency benzotriazole-based ultraviolet absorber, widely used in polymer materials to resist UV-induced aging. It strongly absorbs UV light at 300–380 nm with high light stability and thermal stability, effectively preventing polymer degradation, discoloration, and brittleness caused by UV radiation. In plastics, it is applied to polyethylene, polypropylene, PVC, ABS, PC, and nylon, extending the service life of plastic products. In rubber, it protects rubber products from UV aging and cracking. In coatings and adhesives, it improves the weather resistance of coatings, preventing fading and peeling. It is also used in synthetic fibers, wax products, and cosmetics (limited concentration), providing UV protection. With good compatibility with most polymers and additives, it is a mainstream UV absorber in the plastic and coating industries.

UV-328 is a low-toxicity chemical with mild irritant properties. Inhalation of its dust may cause slight irritation to the respiratory tract, so wear a dust-proof mask and ensure ventilation during operation. Direct skin contact may lead to local redness, itching, or dryness; operators must wear nitrile gloves and wash skin thoroughly with soap and water after contact. Eye contact causes stinging and discomfort; immediately flush eyes with plenty of running water for over 15 minutes and seek medical attention if irritation persists. Accidental ingestion in small doses may cause mild gastrointestinal discomfort (nausea, vomiting); do not induce vomiting and seek medical treatment promptly. It is chemically stable under normal conditions but incompatible with strong oxidants and strong bases; avoid high temperature (over 200 °C) to prevent decomposition. Store sealed in a cool, dry, dark place. Dispose of waste in accordance with local hazardous waste regulations; do not discharge arbitrarily to avoid environmental pollution.