Variable Direct Electromechanical Properties of As-Electrospun Polystyrene Microfiber Mats with Different...

As-electrospun microfiber mats comprising atactic polystyrene (aPS), a low-cost commodity polymer, have demonstrated beneficial electromechanical properties. However, the variability of the electromechanical properties of fiber mats produced using different electrospinning conditions has not been investigated. Therefore, herein, the direct electromechanical properties of aPS fiber mats produced using different deposition times (t_dep) and electrospinning voltages (V_ES) are investigated. The resulting apparent piezoelectric d constant (d_app) of the fiber mats demonstrates a specific peak value for t_dep as high as ~1600 pC N^-1 under 1-kPa pressure application after ~0.2-kPa pre-pressure application, although the d_app of the fiber mats produced with some conditions is nearly zero pC·N^-1. Furthermore, the peak position of d_app with t_dep is fundamentally determined with σ_Eff0/Y_D(h-h_pre) [σ_Eff0: effective surface charge density, Y_D(h-h_pre): secant modulus of elasticity]. Charge distribution models for fiber mats with different t_dep are established. The models explain the characteristics of the significant changes in Y_D(h-h_pre) and σ_Eff0 with t_dep. These findings provide significant directions for the production of fiber mats with improved direct electromechanical properties.