FT-IR Analysis Results of Flexible Substrates According to Various Stress

This study focuses on characterizing flexible substrate materials, especially polyimide (PI) films. We investigated the complexity of molecular structure analysis applied to the film through heat treatment of the substrate before and after rolling to analyze the mechanical properties of the flexible substrate in actual operation. Our experiments were conducted by intentionally adjusting the number of rolling cycles and temperature parameters applied to the flexible substrate. Afterwards, a comprehensive sample analysis was performed using Fourier transform infrared (FT-IR) spectroscopy, which allowed us to thoroughly investigate the molecular composition and structural integrity of the substrate. We also observed changes in the molecular structure due to physical stress through scratch tests on the heat-treated film after the rolling process. Our experimental results confirmed that molecules with weak bonds tend to dissociate under physical stresses such as rolling.