Influence of the Processes Parameters on the Properties of The ...

Chapter 4.
Experimental Procedures and Protocols for Analyses
A graphs obtained from <strong>the</strong> SCION ® data is depicted in Figure 4.25-A. The average pore
diameter, area and volume have been calculated by assuming that <strong>the</strong> pores are perfect circles. Average cell
densities are investigated by <strong>the</strong> following equation:
6 1 foamed
Nc
(1 )
2
(4.1)
de unfoamed
where foamed is <strong>the</strong> density <strong>of</strong> foams, unfoamed is <strong>the</strong> density <strong>of</strong> pellets, d e is <strong>the</strong> pore equivalent
circular diameter, obtained by SCION ® image analysis. (cf. Figure 4.25-B).The types <strong>of</strong> pores in <strong>the</strong>
foams are calculated by <strong>the</strong> following formula that gives <strong>the</strong> circularity.
c = 4 A/P 2 (4.2)
where A is <strong>the</strong> area <strong>of</strong> <strong>the</strong> pores and P is <strong>the</strong> perimeter.
Solving equation 4.2 if <strong>the</strong> results are in <strong>the</strong> range <strong>of</strong> [0.0−0.2], [0.2−0.5] and [0.5−1.0] <strong>the</strong> pores
are elongated, irregular and regular in shape respectively.
Table 4.4: Example <strong>of</strong> pore distribution data, pore morphology and final SCION ® image.
Pore Frequency
100
10
1
0.1
2D Graph 2
d 50
0 20 40 60 80 100 120 140 160
Pore Diameter (m)
100
(A)-Pore frequency and cummulative pore area as
function <strong>of</strong> pore diameter.
80
60
40
20
0
Cumulative Pore Area (%)
Pore Density-( Pores.cm -3 )
1x10 9
100x10 6
10x10 6
1x10 6
100x10 3
0
30
Pore Density : Taguchi Plan-I
60
Cogrinding Time (mins)
180
360
480
1800
3630
4570
(B)-pore density as a function <strong>of</strong> polymer filler cogrinding
time.
Figure 4.25: Graphs obtained from <strong>the</strong> initial data <strong>of</strong> SCION ® image analysis.
The pore numbers does not represent a realist image <strong>of</strong> <strong>the</strong> heterogenous pores in foam, so we
calculate percentage <strong>of</strong> pore numbers, area and volume % <strong>of</strong> micro, meso and macro pores. Different types
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