2025 AIChE Annual Meeting

(554e) Interferometric Measurements of Two Dimensional Polyaramid Thin Films

Authors

Michelle Quien - Presenter, Cornell University
J. Scott Bunch, Boston University
Two-dimensional nanomaterials, such as graphene, transition metal dichalcogenides, and 2D polymers, have intriguing elastic, inelastic, interfacial, resonance, and gas transport and barrier properties. The bulge test platform, wherein a 2D material is suspended over an etched Si/SiO2 well and probed with atomic force microscopy (AFM), has been pivotal in observing these properties as it offers access to these properties at the nanometer-micron scale. Moreover, these tests allow for sensitive measurements, such as the ultra-low impermeability of graphene,16,20,22 which are not possible in the equivalent macroscale experiment. However, this technique has been limited to near-atmospheric temperatures and pressures, as the AFM itself is a highly tuned equipment optimized for ambient conditions. Herein, we develop an algorithm to convert optical light microscopy images of the bulge test platform within a pressurized chamber into height information, thus extending this crucial bulge test platform to a wider range of temperature and pressure conditions. We first create a calibration curve to semi-empirically correlate R, G, and B pixel values with AFM height measurements. Then, we develop a MATLAB algorithm that converts any input optical microscopy image into a bulge height profile. Finally, we showcase the capabilities of our algorithm by analyzing the results of a pressurization experiment at 150 kPa on 2D polyaramid bulge test samples within an environmental chamber and discuss how to extend this to other works.