Poly (Lactic Acid)/Starch Blend for a Degradable Agricultural Mulch Film

Agricultural mulch films are used for the production of vegetables and fruits. Thin plastic films (typically polyethylene) are spread along the rows of plants at the beginning of the growing season. Holes are made in the films to plant the seeds or seedlings. The use of mulch films speeds the ripening of crops, conserves moisture and fertilizer, and inhibits weed growth, fungus infection and insect infestation. At the end of the growing season (generally 3-5 months) the film, contaminated with dirt and vegetation, must be collected, transported and disposed. As the use of mulching films becomes more common, the disposal of the polyethylene film becomes a significant waste problem. This Phase I R&D project will determine the feasibility of producing a degradable agricultural mulch film from a poly(lactic acid)/starch blend. The project will optimize the film formulation and use of crosslinking agents and plasticizers. The film samples will be tested for mechanical properties and usage stability.