Films made of agar and potato starch were elaborated and tested for a potential use as food packaging.
Fourier-transform infrared spectroscopy (FT-IR) confirmed that starch and agar were compatible and
inter-molecular hydrogen bonds existed between them. Scanning electron microscopy (SEM) of composite
film with 15% content of agar showed a compact and homogeneous structure. X-ray diffraction (XRD)
indicated the composite films were amorphous. At 50% relative humidity (RH), the addition of agar could
enhance the tensile strength (TS) from 5.33 to 11.76 MPa. At high moisture environment (75% RH), the
addition of agar could also enhance TS value from 0.84 to 3.36 MPa. Fortunately, the addition of 5% agar
increased the elongation (E) from 32.5% to 58.33%. Water vapor permeability (WVP) decreased from 6.29
to 4.60 1010 g Pa1 s1 m1. In conclusion, the addition of agar improved microstructure of starch film,
and then meliorated mechanical properties and WVP at high moisture environment. It widened the application
of potato starch film in food packaging films as expected.