a) b - École Polytechnique de Montréal

PMMA is selectively extracted while in Figure 6-13b, only the PS is extracted. The micrographs
clearly show a bicontinuous morphology of HDPE and PS with L-PMMA dispersed as droplets
in the PS phase. PS separates the HDPE and L-PMMA. In this case, PS interpenetrates into the
L-PMMA phase rather than the HDPE phase due to lower interfacial tension of PS/PMMA and
the low viscosity of the L-PMMA.
a)
c) d) e)
Figure 6-13. SEM micrograph of morphology of (a) 35/40/25 HDPE/PS/L-PMMA after
extraction of L-PMMA by acetic acid, (b) 35/40/25 HDPE/PS/L-PMMA after extraction of PS
by cyclohexane, (c) 35/40/25 HDPE/PS/H-PMMA(cryofracture), (d) 35/40/25 HDPE/PS/H-
PMMA after extraction of PMMA by acetic acid, and (e) 35/40/25 HDPE/PS/H-PMMA after
extraction of PS by cyclohexane,
In Figures 6-13c) and d), H-PMMA is used instead of L-PMMA and the PS is selectively
extracted to indicate its position. In that case, H-PMMA is present as a few large droplets
encapsulated in thin PS shells(see Figure 6-13c). Figure 6-13d) shows that the PS forms a
b)
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