Indole, also known as indigotin, is a naturally occurring aromatic hydrocarbon found in many plants, including those used for dyeing and flavoring food. It is also used in the production of pharmaceuticals, insecticides, and industrial chemicals.
When rubber is exposed to indole, common types of failure include discoloration, swelling, and softening. Discoloration occurs as a result of the indole's ability to break down the rubber's molecules, resulting in a change in color. Swelling occurs due to the indole's solubility in water, which causes the rubber to absorb the water and expand. Lastly, softening occurs due to the indole's ability to reduce the rubber's surface tension, causing it to become soft and pliable.
Viton ® o-rings from Marco Rubber offer excellent compatibility with a range of chemicals, oils and resist high temperatures up to 400F. Viton ® is also known as FKM made of fluoroelastomer one of the most versatile and widely used sealing materials.
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