After the rubber with a long, sticky soften some will, some will harden brittle. In everyday life, we often see some old tires with the side to produce various obstacles crack, crack is called professional. In this case, the original rubber elasticity, strength is remarkably decreased, which phenomenon is called aging.
Aging is a variety of external factors influence the outcome of a rubber structure changes, the most common is the heat generation of heat and oxygen effects of old age.
Rubber will be heated to a certain temperature degradation. Such as natural rubber over 200 degrees Celsius began to break out of low molecular weight substances. The quality of rubber thermal stability depends on its chemical composition and structure, and thermal stability of the silicone rubber fluorine rubber is better than the other general rubber. In general rubber, butadiene rubber thermal stability is best, followed by styrene-butadiene rubber.
Although the aging of the rubber can not be completely avoided, but can delay the most convenient and effective measure is the addition of antioxidant. Rubber antioxidant can capture thermal aging process produces active substance, and thus play a role in protecting the rubber. |
