29 research outputs found
Preparation of Chitosan-Coated Polyethylene Packaging Films by DBD Plasma Treatment
Polyethylene (PE) packaging films were coated with chitosan
in
order to introduce the antibacterial activity to the films. To augment
the interaction between the two polymers, we modified the surfaces
of the PE films by dielectric barrier discharge (DBD) plasma before
chitosan coating. After that the plasma-treated PE films were immersed
in chitosan acetate solutions with different concentrations of chitosan.
The optimum plasma treatment time was 10 s as determined from contact
angle measurement. Effect of the plasma treatment on the surface roughness
of the PE films was investigated by atomic force microscope (AFM)
while the occurrence of polar functional groups was observed by X-ray
photoelectron spectroscope (XPS) and Fourier transformed infrared
spectroscope (FTIR). It was found that the surface roughness as well
as the occurrence of oxygen-containing functional groups (i.e., CO,
C–O, and −OH) of the plasma-treated PE films increased
from those of the untreated one, indicating that the DBD plasma enhanced
hydrophilicity of the PE films. The amounts of chitosan coated on
the PE films were determined after washing the coated films in water
for several number of washing cycles prior to detection of the chitosan
content by the Kjaldahl method. The amounts of chitosan coated on
the PE films were constant after washing for three times and the chitosan-coated
PE films exhibited appreciable antibacterial activity against <i>Escherichia coli</i> and <i>Staphylococcus aureus</i>. Hence, the obtained chitosan-coated PE films could be a promising
candidate for antibacterial food packaging