Rubber aging in tires. Part 1: Field results

Oxidative aging of skim and wedge rubber inside the tire results in a loss of peel strength and tensile properties of these rubber materials, which has been found to increase the likelihood of tread separations in certain tires. In order to develop an accelerated laboratory tire aging test, we have carried out extensive field and laboratory studies of rubber property change in tires. This paper describes the analysis of rubber oxidation in a specific set of tires collected from the field. In particular, we determine the rate of property loss under worst-case environmental conditions and analyze the implications of variability in aging results. The analysis is used in a companion paper to develop acceleration factors for different laboratory tests.