A NEW APPROACH TO ENHANCING PESTICIDE RESISTANCE IN THE STABILIZATION OF AGRICULTURAL FILMS

In practice, agricultural films must withstand high solar radiation, high temperature in use, mechanical stresses on the film (e.g., film tension across supports, wind), and most importantly, the antagonistic effects of agro-chemicals (pesticides, insecticides, fumigants, soil disinfectants, etc.) on the performance of the UV light stabilizers protecting the film. With pesticide usage, especially sublimed sulfur, increasing worldwide, the demand for UV stabilizers with even greater resistance to pesticides is growing. Evaluation of the UV performance of a stabilized PE film on an actual greenhouse can take three years or more, so accelerated techniques which simulate field exposure would allow for more rapid identification of UV stabilizers with robust resistance. While accelerated UV exposure protocols are widely accepted in the industry for prediction of the service life of plastics, there is no agreement yet on the best methodology to use to simulate pesticide exposure during accelerated UV testing. In this paper, we report on the results of an investigation into the effects of different agro-chemical treatments on PE film life when the films undergo accelerated UV exposure with an agro-chemical treatment. We also report on the development of a new UV stabilizer for greenhouse film stabilization with superior resistance to agro-chemicals.