Synthesis and Characterization of Poly(ethylene furanoate)/Poly(ε-caprolactone) Block Copolymers.

Biobased poly(ethylene furanoate) (PEF)/poly(ε-caprolactone) (PCL) block copolymers have been synthesized using ring opening polymerization (ROP) of ε-caprolactone (ε-CL) in the presence of PEF in different mass ratios. An increase in intrinsic viscosity is observed for the block copolymers with higher ε-CL content due to the extension of their macromolecular chain. Matrix-assisted laser desorption ionization time-of-flight mass spectrometry (MS) was employed to understand the composition and structure of the produced block copolymers. The MS analysis helped to confirm the formation of PEF-PCL copolymers in all cases. Furthermore, tandem mass spectrometry experiments were performed to analyze the intrinsic fragmentation mechanism of neat PEF and PCL (both linear and cyclic) and confirm the block structure and end-groups. Finally, nuclear magnetic resonance results confirmed the composition and microstructure of the block copolymers. The synthesized PEF-PCL block copolymers can be used as a replacement for petroleum derived plastics, especially in the field of food packaging.