Despite sufficient spatial resolution and routine operation, traditional electron microscopy (SEM and TEM) of polymer blend morphologies is limited to two dimensions (2D) and often requires tedious sample preparation. We have used a powerful X-ray imaging technique to visualize the morphology of polymer blends in three dimensions (3D). Images of polystyrene/high-density polyethylene (PS/HDPE) blend samples were constructed with microtomography using coherent synchrotron X-rays. Good contrast for blends with and without the PS phase removed (no other sample preparation was needed) was accomplished, and image quality is compared in the paper. High resolution (1 µm) images of relatively thick (∼1 mm) blend samples were possible by adapting a sample stage equipped with high precision motor controls, by enhancing phase contrast through optimization of sample-scintillator distance, and by taking a large number of projection images (up to 1000) along different angles. Reconstructed slices were used to create 3D volume-rendered images of the blends. Coarsening of the cocontinuous morphology during annealing was monitored using extraction-free microtomography. Measurements of interfacial area per volume at varying annealing times agree with experimental results obtained using mercury porosimetry. It was also shown that SEM quantitative annealing results are limited at long annealing times due to the limitations of two-dimensional images of a three-dimensional morphology.

We have developed a novel strategy for localized electrochemical deposition (LECD) to improve both the lateral resolution of the process and the porosity of the fabricated high‐aspect‐ratio microstructures. The strategy is based on accurately controlling the motion of the anode. Its implementation is made possible by the use of coherent, synchrotron X‐ray microradiography with high time and lateral resolution, enabling the observation of the copper LECD process in real time. Microradiography reveals a deposition mechanism that differs as a function of the distance between the electrode (anode) and the growing structure (cathode). Specifically, the interplay of migration and diffusion of the metal ions in the baths affects the deposition rate and the characteristics of the fabricated structure. This enables us to optimize the anode motion control and greatly improve the quality of the structure grown.

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