Recently the journal ACS Sustainable chemistry & Engineering has published a paper depicting degradation of polypropylene in glucose solution at Department of Chemistry, IIT-Madras. It all started three years ago when researchers at IIT-M observed silver slowly dissolving in a glucose solution when heated to 70 degree C. Now, the team demonstrated an eco-friendly way to degrade chemically inert and physically stable plastic fluoropolymer-polytetrafluoroethylene (PTFE), by which Teflon is made.

To degrade fluoropolymer into molecules, it is required to stir it
continuously in water containing 1000 ppm glucose and metal ions for about 15
days at 70 degree C. Researchers used a magnetic stirrer coated with Teflon to
stir continuously for several days in a glass beaker containing glucose mixed
water and gold foil. The team tested Teflon in different forms like pellets,
tapes and plates. They also repeated the experiment using a Teflon beaker and
tried different metals too and still got the same result each time. The only
difference was the particles did not show bright red luminescence when copper,
silver and iron were used instead of gold. Glucose added to the water first
leaches out ions from the metal surface. When the PTFE-coated magnetic pellet
is ceaselessly revolved within the beaker, triboelectric charges get generated
on the pellet and the PTFE gets negatively charged. Negatively charged PTFE
surface now attracts the metal ions that have been leached out. The interaction
between the metal ions and PTFE ends up in metal-polymer bonding, causing the
carbon-carbon bonds to destabilise. This eventually results in PTFEs degrading
into molecules. No such degradation of PTFE was detected within the absence of
stirring, glucose or metal ions. The rate of degradation gets reduced at room
temperature. The amount of triboelectric degradation depends on the number of glucose
dissolved in water. As the quantity of glucose in water will increase additional
metal ions get leached resulting in additional interaction between PTFE and
also the metal ions. As additional metal ions bind to PTFE, there’s increased
PTFE degradation.