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Adhesion Promoter Needed!

The hydrophobic methyl side groups of Liquid Silicone Rubber (LSR) account for its low surface energy and water repellence. An average value for silicones is 24 dynes/cm or 0.024 N/m. The surface hydrophobicity of a solid surface is determined by its free surface energy. ASTMD2578 (or ISO 8296) is the most employed technique to study loss and recovery of hydrophobicity of silicones, which is calculated by measuring the contact angle. The method is very time efficient, and inexpensive instruments can be utilized. It is often defined on the basis of the static contact angle between the surface and a water droplet, in which a surface can be considered hydrophilic if the contact angle is 90˚.