Experimental and computational studies of ring-opening polymerization of ethylene brassylate macrolactone and copolymerization with ε-caprolactone and TBD-guanidine organic catalyst

The ring-opening polymerization (ROP) of ethylene brassylate, catalyzed by the cyclic guanidine 1,5,7-triazabicyclo[4.4.0]dec-5-ene (TBD) is reported. Several experimental parameters were evaluated for bulk ROP process and polyesters, resulting in molecular weights between 3 and 15 kg mol−1. End-group analysis by 1H nuclear magnetic resonnance (NMR) and matrix assisted laser desorption ionization time of flight computational studies supports the dual behavior of TBD, which can act as both a catalyst and initiator of the polymerization process. Under optimum conditions, semicrystalline poly(ethylene brassylate-co-ε-caprolactone) random copolymers were synthesized. Depending on the comonomer content, our results showed a range of melting temperatures between 39 and 69 °C.