Functionalization and optimization of PLA with coumarin via click chemistry in supercritical CO2

•Click chemistry was carried out at atmospheric and supercritical conditions obtaining a yield higher than 95% in both cases.•Biodegradable polymer was functionalized without the necessity of a ligand at supercritical conditions.•Optimization of operational conditions allowed to stablish the minimum catalyst amount and preferred temperature and pressures.

For the first time the functionalization via click chemistry of polylactic acid (PLA) with coumarin in supercritical conditions CO2 has been achieved. Click reaction was performed at atmospheric pressure and supercritical carbon dioxide (scCO2) for comparison being observed that is possible to obtain similar yields, higher than 95% in both cases. Once click functionalization of PLA in scCO2 was achieved the influence of operational conditions on the polymer characteristics and in the yield was studied to get an optimized functionalization process.