They improved upon the enzyme isolated from a Japanese bacteria that was found to degrade PET.
It was interesting to me that plastic bottle “recycling” is just shredding and using for things like carpet :-/
if you read the bumped Wired piece from B.Joy yesterday, he touches on (his vision of) nanotech's future, and the sorts of molecular recycling options that will come online in the next 12 years.
until then, depolymerization is a hard problem ... so plastic shredding is what we get.
That said, what happens if you grind up + compress + heat those plastics? (it sounds like you understand this better than I do)