When does ozone damage start to affect rubber?

• A. At 1% elongation
• B. At 2% elongation
• C. At 3% elongation
• D. At 4% elongation

Answer: (B)

Ozone damage to rubber begins to manifest when the material is subjected to a strain. Specifically, research shows that rubber starts to exhibit signs of deterioration at 2% elongation. This limit is critical because it reflects the point at which ozone molecules can penetrate the rubber matrix, leading to oxidative degradation. As the rubber is elongated, it becomes more susceptible to the effects of ozone, which can cause cracking and loss of elasticity over time. Understanding this threshold is vital for industries that utilize rubber products, as it helps in the development of ozone-resistant materials and better maintenance practices to prolong the lifespan of rubber in various applications.