Hydrophobic modification of starch via enzymatic grafting polymerization of fluorinated vinyl monomer

The synthesis of starch grafted with poly (hexafluorobutyl methacrylate) (PHFBMA) was achieved using the horseradish peroxidase (HRP)/acetophenone (ACAC) green initiating system. The modified starch was characterized through FT-IR, 19 F NMR, XPS and EDS to confirm the successful grafting of PHFBMA onto starch backbone. The SEM analysis revealed that the introduction of PHFBMA led to a partial disruption of the crystalline structure of starch, suggesting that PHFBMA did not undergo physical adsorption onto starch. Compared to natural starch film, the modified starch film displays a significantly enhanced hydrophobicity, which can lead to substantial improvements in both the hydrophobicity and tensile properties when applied to hydrophilic paper substrates.