Plastics recyclers are usually quite particular about the kinds of plastic (i.e., which plastic resins) they will accept for processing. Reasons include: which plastics are called for in “recipes” for the products they make, how the recycling plant is set-up to handle emissions, and capabilities of the equipment at hand, as well as cost factors. It’s a plus for farmers and those involved with recycling programs to be able to differentiate among the common plastic resins used in agriculture so that sorting and separating can happen at the point of collection. The paper describes and interprets sink-float and burn tests used to identify common plastic resins and describes characteristics of the resins such as density, feel, color, strength and stretchability. These tests and observations can be carried out—even in the field—with minimal supplies.
USDA National Institute for Food and Agriculture Specialty Crops Research Initiative (USDA NIFA SCRI), for the project Optimizing Protected Culture Environments for Berry Crops