Bx53 polarizing microscope

The SP and POM photos of pitches were determined and observed by a CFT−100EX capillary rheometer (Shimadzu, Kyoto, Japan) and a BX53 polarizing microscope (Olympus, Tokyo, Japan).

Transmission electron microscopy (TEM) analysis was performed with a FEI Tecnai TF20 TEM instrument at an accelerating voltage of 200 kV. Samples were prepared by evaporating a drop of dilute GNR solutions in chloroform onto carbon-coated copper TEM grids (400 mesh, TED PELLA, Inc.), which were allowed to dry for 24 h prior to imaging. Freeze-fracture TEM (FF-TEM) images were obtained either on a FEI Tecnai TF30 ST TEM instrument at an accelerating voltage of 300 kV or a JEOL JEM-100S at 100 kV. The FF-TEM samples, replicas of fractured surfaces of the LC-GNR composites, were prepared following a procedure described elsewhere^{51 (link)}. UV-Vis absorption and solution circular dichroism (CD) spectropolarimetry measurements were done using an OLIS spectrophotometer (1 cm path length quartz cuvettes). ¹H NMR spectra were recorded in CDCl₃ on a Bruker DMX 400 MHz spectrometer and referenced internally to residual solvent peaks at 7.26 ppm. Polarized optical microscopy (POM) observations of the induced chiral nematic liquid crystals (N*-LCs) were recorded and photographed using an Olympus BX-53 polarizing microscope equipped with a Linkam LTS420E heating/cooling stage. Differential scanning calorimetry (DSC) was performed using a Pyris 1 DSC instrument (Perkin Elmer). Thermogravimetric analysis (TGA) was performed using a TGA Q500 (TA Instruments).