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Why the tyres are always black?
Published on 02 December, 2015
Student Volunteer at
VEERRACERSS
Carbon black is filler for rubber which are used in tyre. Carbon black imparts strength, wear resistance, fatigue resistance etc.
In addition to the imparted properties , carbon black is an excellent UV block to resist photochemical degradation of the rubber matrix. It is one of the cheapest and most effective UV stabilizers with an excellent track record.
You could make white tyres if you wanted to add Titanium dioxide or zinc oxide but in environments with a moderate to high sulphur (pollution) content in the air, these may darken over time, so black is an excellent default colour.
Any other photochemical stabilizer besides carbon black or titanium dioxide would be orders of magnitude more expensive and not a thermally robust.
Also carbon black is a very efficient opacifier, thus limiting the UV photo degradation to an extremely thin outer surface. White tires have already been successfully obtained, using silica particles instead of carbon black as reinforcement fillers. However, though very nice indeed, their lifespan was very limited, due to the extreme sensitivity of elastomer to UV
In addition to the imparted properties , carbon black is an excellent UV block to resist photochemical degradation of the rubber matrix. It is one of the cheapest and most effective UV stabilizers with an excellent track record.
You could make white tyres if you wanted to add Titanium dioxide or zinc oxide but in environments with a moderate to high sulphur (pollution) content in the air, these may darken over time, so black is an excellent default colour.
Any other photochemical stabilizer besides carbon black or titanium dioxide would be orders of magnitude more expensive and not a thermally robust.
Also carbon black is a very efficient opacifier, thus limiting the UV photo degradation to an extremely thin outer surface. White tires have already been successfully obtained, using silica particles instead of carbon black as reinforcement fillers. However, though very nice indeed, their lifespan was very limited, due to the extreme sensitivity of elastomer to UV