Characteristic changes in the structures and properties of polyimides induced by very high pressures up to 8 GPa

Various in situ measurement techniques have been applied to investigate changes in the three-dimensional structures and the physical properties of polyimides (PIs) generated at high pressures using a custom-built optical cell (up to 4,000 atm) or a diamond anvil cell (up to 80,000 atm). Moreover, the structural changes in the PI chain repeating units and interchain distances induced by the ultrahigh pressures were observed with WAXD, and they were compared with optical absorption, fluorescent and phosphorescent emission spectra, infrared absorption spectra, and refractive indexes observed under the same conditions.

Automated summary

Various in situ measurement techniques were used to investigate changes in the three-dimensional structures and physical properties of polyimides (PIs) generated at high pressures. The changes in the PI chain repeating units and interchain distances were observed with WAXD and compared with optical absorption, fluorescent and phosphorescent emission spectra, infrared absorption spectra, and refractive indexes observed under the same conditions.