2.6. Polarized light microscopy (PLM)
The samples were viewed between crossed polarizers in a Leitz
Diaplan light microscope mounted with
a Linkam hot stage . A droplet of liquid oil was applied on a preheated carrier glass and covered with a preheated
cover glass. The sample was then held at 80 °C for a sufficient
time to ensure complete melting and an erased crystal
memory. Next, the sample was cooled at 10 °C/min to 20 °C and
images were taken using an Olympus color view camera ).