Cycle II Materials Science

John Dewey High School

Mr. Klimetz

Recycling Codes and the Classification and Identification of Common Synthetic Polymers

Introduction. Objects designed as product containers and comprised of synthetic polymer resins currently possess a single digit recycling code.  This code identifies the type of polymer from which the container was constructed and therefore distinguishes one type of polymer resin from another in terms of its chemical and physical properties. There are currently six individual polymer resin classes. The polymer code can be recognized on an appropriate container as a number from one to six surrounded by three curved arrows which collectively capture the number at the center of an upward-pointing triangle. A list of code numbers and the polymer compounds they represent is as follows:

1 = Polyethylene Terephthalate (PET/PETE)

2 = High Density Polyethylene (HDPE)

3 = Polyvinyl Chloride (PVC)

4 = Low Density Polyethylene (LDPE)

5 = Polypropylene (PP)

6 = Polystyrene (PS)

Assignment. You are to find three examples of each polymer resin type from among items in your home such as in your kitchen and bathroom. You may also identify coded objects on the shelves of  your neighborhood store, or perhaps in school. Make a simple chart listing each polymer code, name and abbreviation, and then three items which are composed of this resin type. Most polymers with such codes are usually found in product containers but you may find these codes elsewhere as well. Good hunting. Extra credit will be given to those who bring in their coded objects to share with the class.