Influence Of Filler On The High-Temperature Fatigue Of Natural Rubber

This paper studies the influence of size and structure of carbon black, size of silica, carbon black/silica, tea polyphenol and cure system on basic properties and fatigue performance of vulcanized natural rubber, most focuses on the influence of the factors mentioned above on fatigue performance in high temperature(100oC), and finds out the difference with the fatigue performance in normal temperature(25oC).The results show that there will be a longer fatigue life under high temperature; after the fatigue damage under normal temperature, the crosslinking density of rubber will decreased; after the fatigue damage under high temperature, the crosslinking density of rubber will increased. At first, the crack growth under high temperature is fast, but, when they arrive in a certain degree, it becomes slowly.When the size of carbon black becomes smaller and structure becomes higher, fatigue life of vulcanized rubber will be longer, the influence of temperature on crack growth rate is more obvious. With the increase of size, the initial damage starts earlier under normal temperature and the initial damage starts later under high temperature. The influence of structure on initial damage is not obvious.When adding in tea polyphenols, fatigue life of vulcanized nature rubber filled with two kinds of silica increased obviously under normal temperature and high temperature; it is opposite to high temperature, the crack growth under normal temperature is fast, but, when they arrive in a certain degree, it becomes slowly; the initial damage starts later under high temperature, the phenomenon is more obvious when the rubber filled with 1165 MP.In the system of carbon black/silica, with the increase of silica, fatigue life of vulcanized rubber becomes longer under normal temperature and high temperature. When adding in 40/10, fatigue life improve significantly under high temperature, and crack growth changes obviously.When vulcanizes with t90, vulcanized rubber with CV system has a longest fatigue life under normal temperature, vulcanized rubber with SEV system has a longest fatigue life under high temperature; when vulcanizes with t100, vulcanized rubber with CV system has a longest fatigue life under normal temperature and high temperature. Rubber vulcanizes with t100 has a longer fatigue life under normal temperature, rubber vulcanizes with t90 has a longer fatigue life under high temperature. After aging, fatigue life under normal temperature and high temperature becomes shorter, and from CV to SEV, in turn, increase the fatigue life.