Electrification of a single polymer particle by successive impacting onto metal targets

Electrification of a single polymer particle by successive impacting onto separated metal targets was measured separately about each impact, and, from these experiments, the process of the electrification of the polymer particle due to successive impacts was traced. The experiments were conducted using Teflon particles 3.2 mm in diameter and brass plates (50*50 mm, 5 mm thick) for both the first and second target. These experiments were conducted under a normal-pressure air atmosphere with temperature and humidity maintained at 25+or-5 degrees C and 25+or-5%, respectively. 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 in which the electrostatic field around the particle is considered is proposed. A good explanation of the experimental results was thus obtained.<>