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Technology

This fabrication process consists of three steps; sol-gel extrusion, structure freezing and drying, and a mechanical drawing process. The first step involves subjecting the polymer-solvent solution to a high shear, high temperature, Couette flow extrusion into a thin film, resulting in initial disentanglement. Next, the extruded film is frozen using a liquid nitrogen cooled substrate. During this step, the solvent is removed from the polymer gel through ambient evaporation. Finally the dried film is mechanically drawn in a heated enclosure using a constant-force adaptive-thickness drawing system. The performance of this system has been confirmed by creating highly aligned polyethylene films meters long with draw ratios exceeding 100x and high crystallinity and orientation.