Electrification of Polymer Particles by Impact on a Metal Plate

Impact charge and impact area of particles of nylon 66 and PMMA (3.18 mm and 2.19 mm in diameter, respectively) by a single impact on a metal plate (Cr plated brass plate) were measured under various impact speeds v (3.7 m/s ∼ 20.3 m/s) and impact angles θ(0^°∼80^°). It was found that both the impact charge and the impact area are junctions of the vertical component of the impact speed, v cos θ, while the horizontal component, v sin θ, was found to have no effect on them. The impact area is calculated using the theory of plastic-elastic deformation, and the measured values are found to agree well with the calculations. The impact charge density is constant within the range of the experimental conditions examined and is determined only by the combination of materials colliding with each other.