Synthesis and Characterization\nof Poly(ethylene furanoate)/Poly(ε-caprolactone)\nBlock Copolymers

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