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a) b - École Polytechnique de Montréal

a) b - École Polytechnique de Montréal

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Resistance(ohm)<br />

1.0E+12<br />

1.0E+11<br />

1.0E+10<br />

1.0E+09<br />

1.0E+08<br />

1.0E+07<br />

1.0E+06<br />

1.0E+05<br />

1.0E+04<br />

1.0E+03<br />

1.0E+02<br />

0 5 10 15 20 25 30 35 40 45<br />

Volume fraction of PANI (%)<br />

HDPE/PANI<br />

PEMA/PANI<br />

255<br />

PANI/(HDPE8/PEMA1)<br />

PANI/(HDPE6/PEMA3)<br />

PANI/(HDPE5/PEMA5)<br />

PANI/(HDPE3/PEMA6)<br />

PANI/(HDPE1/PEMA8)<br />

Figure A-4.2. Resistance values for ternary blends of HDPE/PEMA/PANI with various<br />

compositions as a function of volume fraction of PANI<br />

Figure A-4.3 represents the same results as Figure A-4.2 from another point of view, since the<br />

resistance has been plotted against volume fraction of one of the components (PEMA). As<br />

expected, Figure A-4.3 shows higher values of resistance for samples comprising 10% of PANI<br />

compared with samples containing 20% or 30% of PANI. Resistance values of samples<br />

containing 10% PANI are represented in the first curve in Figure A-4.3, revealing that increasing<br />

the concentration of PEMA <strong>de</strong>creases the resistance value of the blend, up to 45% of PEMA.<br />

Further increase of PEMA leads to an increase in the resistance value. This experiment clearly<br />

illustrates the <strong>de</strong>pen<strong>de</strong>nce of the conductivity percolation threshold to sample morphology. The<br />

conductivity value <strong>de</strong>creases when morphology of matrix-droplet for 90/10 HDPE/PANI<br />

changes to matrix/core-shell morphology for the 80/10/10 HDPE/PEMA/PANI ternary blend. At<br />

a composition of 60/30/10 HDPE/PEMA/PANI, shells of PEMA coalesce with each other and<br />

make several connected pathways. The relatively high interfacial tension between HDPE and<br />

PEMA (γPEMA/HDPE = 8.3 mN/m) results in a lower interfacial area value, <strong>de</strong>monstrating the

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