Gluing isn’t always the same
Each one of use comes into contact with adhesives on a daily basis, because: Whether in your home, car or at work – adhesives can be found everywhere. That’s because these days, many materials are bonded together by gluing. But gluing isn’t always the same. There are countless types of adhesives and different types of adhesives have to be used depending on the material composition and area of application. What is gluing and what are the advantages? We explain that in this article.
What kind of glues are there?
Generally speaking, glues are differentiated as those made from natural-based ingredients, e.g. tree resin and/or rubber, tar, caseins or starches, and those made from synthetic ingredients, like epoxy resin, cyanoacrylates, MS polymers or methyl methacrylate.
Why use glues?
Gluing has a long history of joining technology. While rivets were primarily used in the 19th century, and welding was the first choice in the 20th century, the 21st century is designated as the gluing century. There have been a lot of research advancements and today glues can create bonds that are just as strong as welding or rivets. Gluing is getting more and more popular in industry because machine parts can be processed easily, quickly and affordably.
What is the definition of gluing?
Gluing means bonding two or more surfaces together with an adhesive. The glue is anchored by physical interaction, mechanical interlocking and chemical reactions. The strength of the bond depends on the adhesion and cohesion of the glue.
Adhesion
Adhesion is the sum of all the forces that the glue uses to bond with a surface. Good moistening is important for this bond, which means that the glue must cling well to the surface. It should also be as viscous as possible to match the surface. Substances have good moistening properties if they have high surface tension. The lower the surface tension, the more difficult it is for the material to bond.
Cohesion
Cohesion is the sum of all the forces that hold the glue together. Cohesion is caused by three essential factors: physical interaction, chemical bonding strength and mechanical entanglements.
The advantages of gluing
- Bonding various materials (e.g. aluminium, steel, plastic)
- Reduces weight by using lighter materials.
- No surface change (e.g. deformation)
- Even transfer of force, no point loads (unlike screws or rivets)
- Save costs and time
- Additional properties like damping and sealing
- Various design options
Personal protective equipment
Depending on the type, WEICON adhesives and sealants are chemical products that contain various irritants and harmful substances. For this reason, ensure personal protection when using the products, such as using suitable disposable gloves or skin protection. Please also observe the notes in the EC safety data sheet. These safety data sheets can be downloaded free of charge from our website.
Gluing should be well prepared
First, consider what material the objects are made of that you would like to bond together. Not every glue is well suited for any material pair.
Those who have already read some of our blogs know: It’s all about cleaning and degreasing the surfaces. The surfaces must be impeccably clean, which means: free from rust, dirt, dust, oil or grease.
Some materials, such as plastics, might have to be pre-treated by sanding, flame treatment or blasting. The advantage of these pre-treatments is better adhesion.
Which adhesives and sealants does WEICON have in its assortment?
- WEICONLOCK = Anaerobic adhesives and sealants
- Contact = Cyanoacrylate adhesives (superglue)
- Plastic Metal = 2-component epoxy resin systems
- Elastic adhesives and sealants = 1 component polyurethane, MS polymers and silicone
- RK = Construction and assembly adhesives, MMA (methyl methacrylate)
- GMK (rubber metal adhesives), Spray Adhesive = Solvent adhesive
Selection of the right adhesive depends on
- the size of the bonding gap and the surface being bonded
- subsequent stress to the adhesive bond (e.g. environmental influences, temperatures, forces)
- the requirements of individual applications (e.g. hardening time, positioning time, series production)
- the materials being used
The three most important questions
- Which materials are being bonded?
- How big is the bonding gap?
- What kind of stress will the bond be subject to after gluing?
Our Adhesive Finder can answer these questions or help you make a pre-selection.
