Strain and anisotropic effects on migration behaviors of antiozonants in carbon black-filled natural rubber vulcanizates

The influence of strain and anisotropy on the migration behavior of antiozonants in carbon black-filled natural rubber vulcanizates was studied at constant temperatures of 50-90 degreesC and outdoors. N-Phenyl-N'-isopropyl-p-phenylenediamine (EPPD) and N-phenyl-N'-(1,3-dimethylbutyl)-p-phenylenediamine (HPPD) were employed as antiozonants. Migration rates of the antiozonants in the strained vulcanizates are faster than in the non-strained ones. The migration rates in the vulcanizate strained parallel to the milling direction are slightly slower than those in the vulcanizate strained perpendicularly to the milling direction at high temperatures. (C) 2002 Elsevier Science Ltd. All rights reserved.