What kind of adhesive will stick to …?
For just about every possible surface man can find or create there is an adhesive that will stick to it. However, the reasons to use industrial engineering adhesives are for the consistency in the properties of strength and temperature resistance that they bring to the production of finished goods.
The tricky part to choosing the most effective adhesive is matching the conditions that your design requires with the properties of the adhesive.
If a design has failure built as a safeguard to another component the wrong adhesive would be the one that was stronger than the failure point. Conversely, the design that keeps the bench bonded to the wall requires an adhesive that is strong enough for the anticipated passenger load.
Industrial advances in manufacturing have paralleled the changes in the development of engineering adhesives, and widened the range of structural applications. It is therefore important to understand joint design as well as the stresses the bond area will undergo in all stages of production.
Fabric adhesives are used in the fashion industry, auto and home furnishings. Items such as handbags, lamp shades, blinds and the sequins on dress shoes are all bonded with adhesives. Cyanoacrylates, water based adhesives and rubber cement have little long term resistance to water exposure, but can offer fast and flexible bonds to a wide variety of surfaces.
At least four adhesive types will bond metals very well – Anaerobics, Cyanoacrylates, Epoxies and Acrylics – and each has its own set of special features. Metals can be bonded to other metals or to other substrates like plastic or glass. Does your design need fast bonding? Cyanoacrylates might be the answer. Are there mated surfaces requiring a strong flexible seal? Liquid gasket materials are a type of anaerobic adhesive. Toughened acrylics and epoxies each offer high strength solutions for joint integrity and shear resistance.
Some metals will need some surface preparation to remove oxidation, zinc galvanizing, oils or other treatments.
Plastics and Rubbers
The versatile forms of plastic and rubber yield an astonishing number of different adhesive applications with a wide range of requirements. Plastic changes shape over time. Some designs are improved with a flexible grade of a cyanoacrylate. Nothing is better than cyanoacrylate for bonding rubber. For many plastics an epoxy or toughened acrylic will be the answer. Start with a review of the adhesive’s temperature resistance, chemical and environmental resistance from the technical data sheets.
There are many wood adhesives and each is designed to handle a particular requirement. Water resistance is often a first factor in choosing the right adhesive. Joint design and stresses, chemical exposure, existing finishes are all necessary to consider when choosing and applying any adhesive. The type, thickness and age of the wood being bonded may also have an effect on the adhesive selection.
UV curable adhesives provide invisible structural strength bonds that absorb the stresses between the bonded pieces. Within the working range of temperature and environmental conditions, UV is an excellent choice. Epoxy and acrylic adhesives bond glass in conditions of extreme conditions in temperature or environment.
Choosing the Right Glue
The manufacturer is your best source of more information and will likely have Technical Support staff to assist with recommendations and samples. Have your notes ready about the substrates to be bonded, the joint design and the stresses or temperature considerations. Without that information, it is inadvisable to suggest a product. There are some materials or conditions for which other methods of bonding are recommended.