"New" Compounds from Old Plastics: Recycling PET Plastics via Depolymerization

Author Contact: kaufmand@unk.edu

Summary

As landfills begin reaching their capacity and waste generation skyrockets, the world is being forced to take a harder look at recycling. Because it is currently estimated that plastics make up a quarter of landfill space, the recycling of plastics is a hot, current topic.

In this lab, a common plastic, polyethyleneterephthalate (PET), will be depolymerized by a simple hydrolysis reaction. Students can easy perform the hydrolysis and characterize the terephthalic acid in one lab period. If the instructor chooses, an additional lab can be added in which the students convert their terephthalic acid to the dimethyl or diethyl esters (however, these conversions were performed using the less than pleasant methyl iodide and ethyl iodide).

This experiment provides instructors with a framework to discuss waste issues, recycling, polymer chemistry, hydrolysis, carbonyl chemistry, esterifications, SN2 reactions, IR spectroscopy, and proton and carbon NMR spectroscopy.

The supplemental information includes additional background, instructor notes, student procedures, chemical warnings and characterization data.

Summary prepared November 2008 by Douglas M. Young at the University of Oregon.

Category Descriptors

Chemistry Concepts

• Aqueous Solution Chemistry
• Carbonyl Chemistry
• Esters (Reactivity)

Laboratory Techniques

• IR Spectroscopy
• Vacuum Filtration

Green Chemistry Principles

• Prevent Waste

Chemistry Subdiscipline

• Organic Chemistry
• Polymer Chemistry

Target Audience

• Colleges/Universities

Source

• Journal Articles