The Effect of Electric Charges Formed during Repeated Deformations on the Fatigue Resistance of Vulcanizates

Abstract Electroelastic and triboelastic effects result in the formation of electric charges on articles made from polymers undergoing deformation. It was of interest to determine the effect of the charges formed during deformation on the fatigue resistance of vulcanizates. No convincing experiments clearly demonstrating the role of electric charges arising during friction or deformation had been carried out previously. Vulcanizates containing different amounts of acetylene black were tested in a machine in which cylindrical specimens with thickened ends were subjected to repeated bending at 1300 cycles/minute. The stocks had the following composition (in parts by weight) : SKS-30A 100, sulfur 2, technical stearin 2, Rubrax 5, black oil 4, MBTS 0.6, diphenylguanidine 0.8, zinc oxide 5, oleic acid 1. Increasing amounts of acetylene black were added to this composition: 6, 12, 18, 20, 22, 30, 40 and 75 wt. parts per 100 wt. parts of rubber.