29.06.2013 Views

a) b - École Polytechnique de Montréal

a) b - École Polytechnique de Montréal

a) b - École Polytechnique de Montréal

SHOW MORE
SHOW LESS

Create successful ePaper yourself

Turn your PDF publications into a flip-book with our unique Google optimized e-Paper software.

the specific percolation threshold of each of the individual phases (middle, inner, and outer)<br />

significantly <strong>de</strong>creases.<br />

The most critical phases in HDPE/PS/PMMA/PVDF are the first(HDPE) and last(PVDF) phases.<br />

Changing the ratio of these two phases, while maintaining the concentration of the middle phases<br />

controls the evolution of the morphology from an onion structure to a multi-percolated one. It<br />

has been shown in previous work from this laboratory(Reignier, et al., 2003) that composite<br />

droplets with a core/shell morphology can experience coalescence and still maintain the<br />

hierarchical or<strong>de</strong>r after coalescence. Figure 4-7a-e, which shows quaternary<br />

HDPE/PS/PMMA/PVDF blends of concentrations of 60/13/13/13(onion morphology),<br />

50/17/17/17, and 30/15/15/40(multi-percolated morphology), illustrates that the hierarchical<br />

or<strong>de</strong>r is maintained as the morphology transits from an onion structure to more elongated<br />

structures through to a multi-percolated one. Figure 4-7e shows unambiguously, after the<br />

selective extraction of the PMMA phase, that highly or<strong>de</strong>red multipercolated morphology is<br />

obtained for 30HDPE/15PS/15PMMA/40PVDF with a hierarchical or<strong>de</strong>ring of<br />

HDPE/PS/PMMA/PVDF.<br />

116

Hooray! Your file is uploaded and ready to be published.

Saved successfully!

Ooh no, something went wrong!