Sealants and Adhesives
Definition and Introduction
Basic concept of sealants and adhesives
Sealants and adhesives are essential materials in construction, used to bond and protect surfaces, ensuring structural integrity and impermeability. Adhesives are substances that allow a permanent or semi-permanent bond between two surfaces, creating a chemical or physical adhesion, while sealants are used to fill, seal and protect joints or cracks against external agents such as water, air, dust or contaminants.
In construction practice, both products play a fundamental role in improving the durability, functionality and aesthetics of buildings. Although they are often used together, their properties, composition and specific applications vary considerably, adapting to different technical and environmental requirements.
Types of Sealants and Adhesives
Classification of sealants according to their chemical base
Sealants can be classified based on their chemical composition, with the most common being silicone-based, polyurethane, acrylic, polysulfide, and MS polymer-based sealants. Each type offers particular characteristics in terms of elasticity, weather resistance, adhesion and compatibility with different materials.
For example, silicone sealants stand out for their excellent resistance to ultraviolet radiation and humidity, making them ideal for facades and windows. Polyurethanes offer high elasticity and mechanical resistance, suitable for joints subjected to dynamic movements and stresses. On the other hand, acrylics have good adhesion and are easy to paint, although they have less elasticity and water resistance.
The choice of the appropriate sealant depends on factors such as the type of substrates, environmental conditions, expected movements in the joint and aesthetic requirements, being essential to guarantee the durability and functionality of the sealing.