Polyurethane Sealant 3M™ 540 3M™ The 3M™ polyurethane sealant is a single-component product used for bonding, sealing, and waterproofing in various industrial sectors, including automotive, construction, and marine. This sealant is known for its strong adhesion to numerous surfaces such as metal, wood, glass, concrete, and plastics. Once applied, it cures by reacting with moisture in the air to form a flexible, durable joint that is resistant to vibrations, weathering, and UV rays. This sealant is particularly valued for its ability to create durable joints that remain flexible even under harsh conditions. It is commonly used for tasks such as joint sealing, panel bonding, and part assembly. Its single-component formula makes it easy to use, with no need for prior mixing. Learn more