UV Absorber 329 CAS 3147-75-9

UV Absorber 329 is a benzotriazole-based ultraviolet light stabilizer, chemically known as 2-(2H-benzotriazol-2-yl)-4-(1,1,3,3-tetramethylbutyl)phenol. It appears as a white to pale yellow crystalline powder, with a faint characteristic odor. Practically insoluble in water, but soluble in organic solvents such as acetone, chloroform, ethyl acetate, toluene, and methylene chloride. Commonly used as a light stabilizer in plastic and polymer industries to protect materials such as polyvinyl chloride, polyolefins, polystyrenics, polycarbonate, polyesters, acrylic resins, and engineering plastics from UV-induced degradation, yellowing, and surface cracking. Also functions as a UV absorber in coatings, paints, adhesives, sealants, and packaging films to improve outdoor weatherability and extend service life. Exhibits good thermal stability and low volatility. Stable under normal storage conditions and should be kept in tightly sealed containers away from light, moisture, and strong oxidizing agents.