The use of adhesive materials as a bonding and sealing system is experiencing a great boom and huge growth in the areas of construction, manufacturing, and maintenance due to the several advantages that this kind of material provided. Without their use, it would be impossible to manufacture materials or products necessary in our daily life. For example, sandwich or honeycomb panels used in multiple sectors, which provide an extraordinary resistance combined with a very reduced weight; medical material such as bandages or band-aids; office material such as post-it, decorative materials such as vinyl and stickers, and so on.
For this reason, a wide range of sectors and industries use bonding materials as part of their processes, including the building sector. Companies like Harwal offer a different kind of adhesives designed to be used in the construction of complex structures such as skyscrapers, airplanes, locomotives or buses. The aeronautical industry was the first sector that promoted their use in construction processes to build airplanes, rockets or helicopters, due to its extraordinary advantages over traditional methods such as welding or screwing. Later on, other industrial sectors began to use adhesives as a bonding material to improve their products.
Choosing the best adhesive for a specific application can be complex. There are many variables to consider and numerous types of chemicals with different capacities. Understanding the following parameters will help reduce the options, and selecting the right adhesive will reduce the number of products to be coated. Here’s the essential information you need before you know which one to use.
How to choose the best adhesive
Adhesives work by attaching to the top surface of the bonded parts, so it is important to know the material and the exact conditions of those surfaces. For metals, will the adhesive be applied to the bare metal, or will there be paint or coating on the surface? For plastics, what base resin to use? Could there be residual release agents on the surfaces used? The different chemical compositions, on the other hand, provide unique advantages. Depending on the requirements in terms of mechanical strength, durability or flexibility some chemicals may be more suitable than others.
The binding chosen must have to last enough time open to allow proper mixing, application, and assembly of the bonded parts. Smaller assemblies or shorter cycle production processes may use a faster curing adhesive with a useful life of only five minutes or less, while larger assemblies which require alignment and fastening will probably need an adhesive wich EOL is longer than 20 minutes or more.
Types of adhesives used in construction
Resins
Resins provide a unique combination of elasticity and resistance. This versatility is ideal for numerous lightweight applications since they are perfect to fill gaps, they offer greater design freedom, high resistance to impact and they prevent crack propagation. Resins also withstand high dynamic loads and have excellent chemical and aging resistance.
Acrylic
Acrylics are usually monomers based on methacrylate ester or acrylic base. They are organic, synthetic, polymerization reagents. Acrylics can be single-component or two-component. They are capable of bonding a wide variety of materials. They have good thermal resistance and provide high tenacity joints.
Epoxy
Epoxy show excellent adhesion properties on almost all industrial materials, which allows for extensive freedom in design and cost optimization in manufacturing processes. They provide greater resistance to impact and fatigue and are therefore better adapted to dynamic efforts. They have long term durability, higher resistance to friction and much greater resistance to shocks, vibrations, and impact.
Hot melt adhesives
Hot melt adhesives allow the user to harden and soften them whenever they want, using cold or heat. They feature an excellent bonding quality and once heated can bond really fast to materials.
Tape and contact sprays
Adhesive tape is perfect to work with glass, while contact sprays –which are waterproof and don’t leave stains can be used on uneven and porous surfaces.
How to apply adhesives in construction?
The use of adhesives in building processes generally requires clean, dry surfaces to increase bond strength. This typically means light abrasion and solvent, chemical cleaning of the Surface prior to the application. It is also advisable also to run adhesion tests to determine the appropriate surface preparation for a specific application. Once the surface is clean and ready, follow the manufacturer’s instruction, since every kind of adhesive has to be applied differently. They are available in many forms, including low-viscosity liquids and thixotropic pastes; one- and two-component formulations, with short and long working times; and various container sizes and shapes. Most of them are available in both container and cartridge systems, to make them more convenient and easy to use.