Poly(GBL) has another property that makes it even more useful as an environmentally-friendly source of plastic. The researchers developed a reverse thermal reaction that caused the polymer to revert to its original monomer form. Unlike current bioplastics such as PLA that are only partially biodegradable, this reverse reaction makes poly(GBL) completely recyclable. Bioplastic objects made from the poly(GBL) material can be recovered from the waste stream and recycled using a thermal reaction that converts the plastic polymer back to its monomer form. Once recovered, the GBL monomer (recyclable biopolymer) is ready again for use in future plastic products.
This recyclable biopolymer breakthrough could open the door for the production of a bioplastic material that is not only petroleum-free, but that can also be recycled easily under heat. Knowing its market-changing potential, Chen has filed a provisional patent for the discovery. “In my 15 years at CSU, I would probably call this my group’s most exciting piece of work,” Chen said in a statement. “This work creates a class of truly sustainable biopolymers, as they are both biorenewable and recyclable, based on a bioderived monomer previously declared non-polymerizable.” Chen and postdoctoral fellow Miao Hong described this discovery in a recent issue of Nature Chemistry journal.