Abstract
In this study, baked starch foam was prepared from corn starch, using water as a non-toxic
blowing agent. Some additives e.g., guar gum, magnesium stearate, kaolin, and glycerol, were
added to improve the properties of the foam. Chemical structure of the foam was confirmed
by Fourier-transform infrared spectroscopy (FT-IR). Scanning electron micrographs (SEM)
revealed that the foam showed smooth surface with the addition of the additives.
When beeswax was added, the foam surface roughness increased with increasing beeswax
concentration. Hardness test (Shore C) showed a slight increase in the foam hardness when
beeswax concentration increased. Moreover, it was found that the moisture absorption
capacity of the foam at 50 %RH decreased with increasing beeswax concentration. Water
resistance test confirmed that beeswax played an important role in the dimensional stability
of the foam while soaking in water for 12 hrs at room temperature (29 ℃). Convincingly,
the baked foam prepared from corn starch mixed with the additives and 20 parts per
hundred (phr) of beeswax showed the best properties among the developed foams. Besides,
such the foam can be totally degraded in soil mainly via hydrolysis.
