Organocatalytic depolymerization of poly(trimethylene carbonate)

Aliphatic polycarbonates have attracted attention as degradable and sustainable materials contributing to the circular plastic economy. Their chemical recycling has not been sufficiently studied. In this study, efficacy of organocatalysts for depolymerization poly(trimethylene carbonate) (PTMC), a representative aliphatic polycarbonate, is investigated using several organic acids bases. The hydrolysis PTMC produces water-soluble degradates propane-1,3-diol (PD) CO2. A phosphazene base P2-t-Bu shows high activity hydrolysis, yielding up 31% 89% PD in homogeneous reaction at around 27°C inhomogeneous under reflux condition, respectively. By contrast, 1,5,7-triazabicyclo[4.4.0]dec-5-ene (TBD) exhibits exceptionally catalytic methanolysis PTMC, producing dimethyl carbonate. This because dual hydrogen-bonding activation, which completes few hours while more than 90% PD. rate TBD-catalyzed depends on concentration nucleophile catalyst, ratio substrate affects yield. These results provide highly promising standard functionalized that could potentially be applied future.