Chemistry Reference
In-Depth Information
FIGURE 5.4
AFM topographic images of PHB films (170 kDa) with a scan size of
18×18 μm: (a) the rough surface of fresh-prepared sample (exposed to air); (b) the smooth
surface of fresh-prepared sample (exposed to glass); (c) the sample exposed to phosphate
buffer at 37 °C for 83 days; (d) the sample exposed to phosphate buffer at 70 °C for 83
days. General magnificence is 300.
Inequality of morphology between two surfaces gets clearly evident
when quantitative parameters of roughness (r
n
) were compared. A rough-
ness analysis has shown that averaged value of this characteristic and a
root mean square roughness for surfaces exposed to glass or air differ
about ten times.
1
N
∑
R
r
a
=
n
N
n
=
1
1
N
=√
∑
2
R
r
q
n
N
n
=
1
