a) b - École Polytechnique de Montréal

composition of PS was controlled to generate a PS shell down to a few hundred nm between two
continuous PS and PMMA structures (Figure 5-2b). Subsequently, the PS and PMMA phases
can be extracted, yielding a fully interconnected porous HDPE substrate of about 60% void
volume. This method can be employed to prepare substrates with higher void volume. For
instance, in the 40/10/50 HDPE/PS/PMMA ternary blends if one could obtain a selective solvent
for HDPE, the combined removal of HDPE and PMMA would yield a highly porous PS
substrate of about 90% void volume.
a)
b)
HDPE
PMMA
PS
PMMA PMMA
HDPE
Figure 5-2. (a) FIB-AFM topographic surface image of 40/20/40 HDPE/PS/PMMA. The
topographical height vs distance is shown to the right. The white line in the image indicates the
trace line used in the height vs distance analysis. and (b) Scanning electron micrograph of
40/10/50 HDPE/PS/PMMA after extraction of the PS phase by cyclohexane
HDPE
PS
PMMA
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