a) b - École Polytechnique de Montréal

less etched than HDPE which is less etched than PS(Virgilio, Favis, Pepin, Desjardins, &
L'Esperance, 2005a). The positive spreading coefficient of PS over PMMA (λPS/PMMA) with a
value of 2.6 mN/m predicts the development of a thermodynamically stable PS layer between the
PE and PMMA phases and is a direct result of the very high interfacial tension of PMMA and
HDPE(γHDPE/PMMA = 8.4 mN/m).
a)
PS
HDPE
PE
PS
PMMA
PMMA
PMMA
Distance (µm)
PS
PE
b)
Figure 4-3. a) FIB-AFM image of the composite-droplet morphology of 30/10/60
HDPE/PS/PMMA showing PS as a layer separating HDPE and PMMA. Scan size is 5μm×5μm.
The bar to the right of the FIB/AFM micrograph indicates the colours associated with the
topographical height in nm. The white line in the image indicates the section analyzed below,
and b) SEM micrograph of a 45/10/45 HDPE/PVDF/PANI blend after extraction of the PVDF
phase by DMF. The voids show that PVDF was present as a layer separating HDPE and PANI.
Table 4-2 represents the surface tension and polarity of the various polymers being used in the
harmonic mean equation(Wu, 1982) for interfacial tension. Table 4-3 shows a range of
interfacial tension values of polymer pairs, including PANI with other polymers, estimated using
the harmonic mean equation. A number of these interfacial tensions were also measured
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