Facile microfluidic fabrication and characterization of ethyl cellulose/PVP films with neatly arranged fibers

Much attention and endeavor have been paid to developing biocompatible food packaging films. Here, ethyl cellulose (EC) and polyvinylpyrrolidone (PVP) were fabricated into films through a facile method, microfluidic spinning. Morphology observations showed that the fibers were neatly arranged with an average diameter of 1-4 μm. FTIR and X-ray diffraction analysis suggested the existence of good compatibility and interaction between EC and PVP. Thermogravimetric analysis demonstrated that PVP ameliorates the thermal properties; moreover, the tensile properties were improved, with tensile strength (TS) and Young's modulus up to 11.10 ± 1.04 MPa and 350.16 ± 45.46 MPa, respectively. The optimal formula was EC/PVP (2:3), of which the film displayed an enhanced TS of 4.61 ± 1.15 MPa and a modified water contact angle of 61.8 ± 4.4°, showing fine tensile and hydrophilic performance. This study provides a facile and green film fabrication method promising to be used for food wrapping.

Microfluidic spinning of poly (methyl methacrylate)/konjac glucomannan active food packaging films based on hydrophilic/hydrophobic strategy

Here, inspired by the hydrophilic/hydrophobic theory, a novel konjac glucomannan/poly (methyl methacrylate)/chlorogenic acid (KGM/PMMA/CGA) food packaging film was successfully fabricated via microfluidic spinning technology (MST). The results of fourier transform infrared spectroscopy and x-ray diffraction confirmed the formation of hydrogen bonds in the films, which lead to the enhanced mechanical properties. Thermogravimetric analysis and differential scanning calorimetry showed excellent thermal stability of the films. Water vapor permeability (1.47 × 10^-5 ± 0.11 g/(m⋅h⋅kPa)) and water contact angle (89.2°) measurement proved that the films were hydrophobic. The good swelling degree (85.18 ± 15.65%) indicated film's potentials in releasing CGA. More importantly, KGM played a key role in the antibacterial activities against Staphylococcus aureus (8.5 ± 3.5 mm) and Escherichia coli (6.5 ± 2.1 mm) by utilizing its hydrophilicity. Thus, our present work may provide a new idea for constructing active food packaging films with significant performances based on hydrophilic/hydrophobic strategy.