Stabilization of agricultural films: Past, present, and future

Agricultural films must resist weathering due to sunlight, but have the additional requirement of chemical resistance. An evolution of stabilizers is ongoing for all polyolefins and is especially evident in the agricultural film market: ''The Past''-Historically, nickel quenchers and benzophenone UV absorbers were used to protect films from UV degradation. As nickel quenchers are being phased out of the market for environmental reasons, new stabilizers need to be developed. ''The Present''-Hindered amine light stabilizers (HALS) systems based on tertiary HALS offer an efficient approach to UV stabilization and have replaced nickel quenchers and UV absorbers in many applications. Highly efficient chemical-resistant light stabilizer systems have been developed with high molecular weight tertiary HALS and coadditives. ''The Future''-Market needs for longer lived greenhouses and thinner mulch films will require even more powerful stabilizers. New non-interacting chemistries based on alkoxyamine HALS offer the next generation of stabilizers for agricultural films.