Polyesters have been used in many applications, but there have been relatively few reports of depolymerization. Rapid and efficient degradation processes using catalysts have also been reported mostly in PET.^[1] We have carried out the depolymerization of various polyester such as Polylactic acid (PLA), Polypropylene carbonate (PCC), Polycarbonate (PC), Polyethylene terephthalate (PET) and Tritan^®. We tried to show the efficiency of each catalyst using organic and metal complex catalyst used for transesterification. As a result, 1,8-Diazabicyclo[5.4.0]undec-7-ene (DBU) and 1,5,7-Triazabicyclo[4.4.0]dec-5-ene (TBD), which are organic base catalysts, showed excellent results with high efficiency as known from PET.^[2] Although ZnTAC24^®, a Zn metal catalyst, was inferior to an organic base, it was more reactive than Titanium isopropoxide and Tosylic acid. Both PLA, PCC and PC could decompose under the easier conditions than PET. However, a commercial polymer Tirtan® is more difficult to decompose due to its poorly soluble properties.

Reference
^[1] N. George, T. Kurian, Ind. Eng, Chem. Res., 2014, 53, 14185-14198.
^[2] H. W. Horm, G. O. Jones, D. S. Wei, K. Fukushima, J. M. Lecuyer, D. J. Coady, J. L. Hedrick, J. E. Rice, J. Phys. Chem. A, 2012, 116, 12389-12398.