Chemically speaking, rubber-based adhesives are classified as elastomers.
A general principle of adhesion is that the best adhesives often contain a component of the materials it must bond.
Three excellent adhesives for rubber to rubber applications are:
- Rubber-based adhesives, like nitrile elastomers, work extremely well when bonding rubber to itself.
- Thermoplastic glues, especially cellulosics, bond well to rubber and have other desirable applications and properties suitable for the manufacturing and construction industries.
- Polyamide epoxies have excellent bonding properties and durability when used for joining rubber parts.
If your application requires rubber to rubber bonding, call and talk to a member of our team. It’ll save you time and you won’t have to guess about the most suitable of the three adhesives listed above.
Especially if you have a rubber-ish to rubber-ish product, which might require a custom formulation to get your business the best performance and value.
The Advantages of Adhesive Bonding versus Mechanical Fasteners
Whether rubber materials are to be attached to other rubber materials or dissimilar materials, adhesives usually trump mechanical fasteners for a number of reasons:
- Often, mechanical fasteners are insufficient on their own so adhesives are required anyway.
- Product design is complicated mechanical fasteners, as holes and bosses must be included.
- Product appearance is usually compromised by fasteners, whereas adhesives are invisible.
- Fasteners cause localized stress on the adhesive, undermining its capability.
- Mechanical fasteners are more expensive because of the material requirements.
Rubber-based adhesives come in many flavours. Natural rubber latex and natural rubber solutions have been in use for several decades in the B2B industry.
Nitrile synthetic rubber adhesive is widely used on natural and synthetic rubber materials.
Several types of phenolic-based rubber adhesives work well with most types of rubber, as do resin-rubber blended glues and some polyurethanes.
There is no one-size-fits-all when it comes to bonding rubbers, as cyanoacrylates demonstrate.
Cyanoacrylates are a type of cellulosic adhesive that is used for many applications, including rubber.
They require no mixing and cure rapidly at room temperature. They come in an astounding array of special formulations to match almost any rubber bonding application.
When toughened with rubber additives they boast high impact resistance and peel, shear and tensile strength.
They can also be formulated to withstand high temperatures over extended time periods.
Epoxies are a type of thermoset polymer adhesive that form bonds between two components: the epoxy resin and its hardener.
The addition of an optional third component, a chemical catalyst, is used to accelerate cure times.
Though these adhesives require mixing and generally have long cure times, they bond well to rubbers and provide a tough and environmentally insensitive adhesion.
Epoxies derive their exceptional strength from interchain hydrogen bonding, which is a special type of polymer crosslinking.
The Importance of Surface Preparation
Compared to other substrates, elastomeric materials such as rubber are more fluid, which can permit contaminants and other low molecular weight materials to migrate to the surface.
These may create a boundary layer that weakens any subsequent adhesive bond.
Furthermore, rubber-based materials typically exhibit low energy surfaces that prevent high adhesion.
Thus, preparation of the rubber surface by abrasion, solvents or primers is essential to obtain strong bonds.
Primer solutions are applied to one or both parts to be joined and then air or heat dried before applying adhesive.
They are particularly useful when bonding unvulcanized rubber to itself or when bonding rubber to metal equipment & supplies.
Rubber Bonding Solutions to Fit Your Application
Despite the wide array of application processes, and service and environment requirements for end products, there is bound to be at least one adhesive, probably several, for any industrial or commercial rubber-to-rubber bonding need.
Choosing one is a matter of weighing material and production costs along with durability, stress resistance and safety requirements.
We can help you find the right adhesive for the job, no matter what industry you’re in. Give us a call today.