Electrification of single polymer particles by successive impacts with metal targets

Electrification of single polymer particles by successive impacts with separated metal targets was measured separately for each impact. From these experiments, the process of the electrification of the polymer particle due to successive impacts was traced. At the second impact, the initial charge of the particle becomes nonuniform because of the presence of the impact charge generated by the first impact. In order to account for the contribution of this nonuniform initial charge on the impact charging, a new model was proposed in which the electrostatic field around the particle was considered. Our experimental results were discussed based on the new model.