Back in the day, "greenwashing" was a term that was used quite liberally to describe products or technologies that didn't live up to their claimed environmental bona fides. You don't tend to see that term much anymore, but it's what immediately comes to mind when I think of compostable plastics. "Compostable", when examined more deeply, ends up meaning "compostable given some probably unrealistic length of time".
On the subject of municipal compost -- we've had curbside compostables (Green Bin) collection for about 13-14 years now. It's never been clear that this project is beneficial from a life-cycle point of view. Apparently, the resulting compost is not very useful -- it's too salty to actually grow plants with, due to all the food waste in the input stream.
I suspect that you're right about "degrade on command". Instead of enzymes, it might be accomplished with high pH or oxidants, and end up as a form of chemical recycling. Even then, one can't help but think that the real solutions have to come from reduction and reuse, or perhaps even (shudder) incineration.
Back in the day, "greenwashing" was a term that was used quite liberally to describe products or technologies that didn't live up to their claimed environmental bona fides. You don't tend to see that term much anymore, but it's what immediately comes to mind when I think of compostable plastics. "Compostable", when examined more deeply, ends up meaning "compostable given some probably unrealistic length of time".
On the subject of municipal compost -- we've had curbside compostables (Green Bin) collection for about 13-14 years now. It's never been clear that this project is beneficial from a life-cycle point of view. Apparently, the resulting compost is not very useful -- it's too salty to actually grow plants with, due to all the food waste in the input stream.
I suspect that you're right about "degrade on command". Instead of enzymes, it might be accomplished with high pH or oxidants, and end up as a form of chemical recycling. Even then, one can't help but think that the real solutions have to come from reduction and reuse, or perhaps even (shudder) incineration.