Functionalization of aliphatic polyesters by nitroxide radical coupling
- Authors: Cicogna, F.; Coiai, S.; Rizzarelli, P.; Carroccio, S.; Gambarotti, C.; Domenichelli, I.; Yang, C.; Dintcheva, N.T.; Filippone, G.; Pinzino, C.; Passaglia, E.
- Publication year: 2014
- Type: Articolo in rivista (Articolo in rivista)
- OA Link: http://hdl.handle.net/10447/96361
Abstract
Functionalized poly(butylene succinate) (PBS) samples were prepared by a post-polymerization method based on the coupling reaction between TEMPO derivatives bearing different functionalities and PBS macroradicals generated by H-abstraction using a peroxide. 4-Benzoyloxy-2,2,6,6-tetramethylpiperidine-1- oxyl (BzO-TEMPO) and 4-(1-naphthoate)-2,2,6,6-tetramethylpiperidine-1-oxyl (NfO-TEMPO), a pro-fluorescent nitroxide, were successfully grafted on PBS, as revealed by MALDI TOF MS and UV-Vis spectroscopy. The functionalization degrees were accurately determined by UV-Vis analysis and confirmed by 1H-NMR spectroscopy. The grafting site was identified by combining theoretical calculations with experimental evidence. This evidence was collected by both EPR analysis of a functionalized sample subjected to controlled heating in the EPR cavity, and by 1H-NMR spectroscopy. Our functionalization method, which was also tested for poly(lactic acid) (PLA), preserves the original polymer structure. T...