Theoretical and Experimental Investigation of Physical Mechanisms Responsible for Polymer Nanofiber Formation in Solution Blowing

This work describes a comprehensive numerical model of solution blowing process of multiple threedimensional polymer jets issued from a die nosepiece into a high-speed air flow and deposited onto a moving screen. The model solves the quasi-one-dimensional equations of the mechanics of free liquid jets with the jet axis configuration being three-dimensional. It accounts for the polymer solution viscoelasticity, jet interaction with the surrounding high-speed air flow, and solvent evaporation and jet solidification. The results include the polymer jet configurations in flight as well the detailed information on the pattern in which the oncoming polymer jets are deposited on the moving screen (the so-called lay-down), and its characteristics, in particular, the fiber-size distributions obtained under different conditions. The work also describes experiments on solution blowing and comparison of the numerical and experimental data.