Abstract
Over the past four decades, advances in polyolefin stabilization have helped manufacturers expand their material choices to capture economic and performance benefits. In the ’60s and 70s, antioxidants and UV absorbers provided baseline levels of protection against thermal and UV degradation. During the 1980’s hindered amine light stabilizers substantially extended the service life of polyolefins for a multitude of film, fibre and moulded articles. In the last ten years, breakthroughs in hindered amine chemistry have pushed the performance boundaries of polyolefins to even greater heights.
Now, in the ’90s, the elimination of undesirable aspects of hindered amine stabilization, such as amine deactivation in flame retardant systems and reduced colour yield in pigmented plastics, is allowing material substitution in markets traditionally earmarked for engineering polymers, glass and metal. This paper focuses on advances in hindered amine chemistry designed to address these shortcomings. Examples of applications where new hindered amines provide enhanced value are demonstrated. Performance data are presented for polypropylene fibre, thermoplastic olefins for automotive parts and construction applications, polyethylene agricultural film and flame retardant systems. The advantage of using hindered amines as thermal stabilizers is also discussed.