Does natural rubber have antidegradants?

Natural rubber already contains naturally occurring antioxidants that protect the polymer from oxidation. One of the key properties of antidegradants (antioxidants and /or antiozonants) is their solubility in the rubber matrix. The faster the rate of bloom, the less soluble the antidegradant is in the polymer system.

Which polymers have antioxidants added to their latex phase?

Nitrile, SBR, polychloroprene and synthetic polyisoprene are examples of polymers that have antioxidants added to their latex phase of processing to protect them from oxidation. Natural rubber polymers normally do not need the addition of “polymer stabilizers” to be protected against oxidation.

When were antioxidants discovered?

These chemicals became known as “Antioxidants”. The discovery of “Antiozonants” occurred early in the 20th century, but it wasn’t until mid-way through the century before they became widely used. It was discovered that rubber articles (mainly tires) stored for several years quickly failed when put into use.

What happened to natural rubber elastomeric polymer?

Natural rubber was the only elastomeric polymer available for commercial use at that time. Articles made from natural rubber would soon become soft and tacky. They would no longer be serviceable. Chemists determined the cause of degradation and pre-mature failure of rubber articles was due to reaction with oxygen in the atmosphere.

Why do antioxidants react with hydrocarbon radicals?

Antioxidants (and antiozonants) react with these radicals to terminate the chain reaction causing oxidation of polar polymer systems; thereby prolonging the serviceability of a rubber article. Antioxidants also react with hydrocarbon radicals when they are formed.

What happened to rubber in the 19th century?

In the late 19th and early 20th centuries, articles made from rubber had very poor weathering characteristics. Natural rubber was the only elastomeric polymer available for commercial use at that time. Articles made from natural rubber would soon become soft and tacky. They would no longer be serviceable.