Influence of hot air aging on basic properties and fatigue failure characteristics of tread rubber
The influence of hot air aging on the basic properties and fatigue failure characteristics of the tread compound of heavy-duty tires was investigated through instruments and equipments such as Fourier transform infrared spectroscopy,dynamic thermomechanical analyzer,hot air aging chamber and dynamic fatigue testing machine.The results show that as the hot air aging time prolongs,the crosslinking density and Payne effect of the rubber first increase and then decrease,while the tensile strength and tear strength decrease;the modulus and hardness increase,and the carbonyl content produced by the oxidation of double bonds in the molecular chain increases.In the early stage of fatigue,the weak bonds inside the rubber material are broken,the carbon black network is damaged,and the degree of early damage caused by the detachment of carbon black aggregates from the rubber matrix is intensified.The larger the amplitude of the change in modulus,the more obvious double peaks the fatigue history curve appears.The fatigue history curve decreases significantly in the later stage,and the fatigue failure rate of the rubber material accelerates,resulting in a decrease in fatigue life.During the process of tensile fatigue,some NR macromolecules undergo isomerization,forming a small amount of trans configuration.
tread rubberhot air agingstructurefatigue characteristicsfatigue history curve
万方数据
维普
