When you need to adhere two or more surfaces together, it is not always easy as grabbing whatever type of glue you have close by. Different materials require vastly different adhesives, and using the wrong one could cause serious problems. Rubber is one material that is notably difficult to bond. It comes in many different types and is used in a wide range of applications requiring diverse electrical, thermal, chemical and physical properties. The adhesives you use, of course, must also satisfy these requirements. There are several things you need to know and do when bonding rubber. Let’s take a closer look.
Types of Rubber
There are numerous types of rubber on the market, and some are more common than others. Some of the ones that you are most likely to encounter include nitrile rubber, butyl rubber, polyurethane rubber, silicone rubber, EPDM rubber, and natural rubber. There are countless others, too, but these are the ones we see most often in our daily lives in the form of things like hoses, gaskets, inner tubes, seals, etc.
Preparing Rubber for Bonding
No matter what type of rubber you are working with, properly preparing it is the first step to a successful bond. Start by performing a thorough solvent degrease to remove things like slip additives, mold release, and other processing lubricants. A quick wipe with isopropanol is usually your best bet, as acetone may be too strong for certain types of rubber.
What Type of Adhesive to Use
In general, cyanoacrylate instant adhesive is the best choice for bonding rubbers. More commonly known as super glue, this product cures in just seconds and lets you know quickly whether or not the bond will hold. When applying cyanoacrylate, apply only a tiny drop and make sure both surfaces are squeezed together tightly. If the bond fails quickly, you may be dealing with one of the more challenging types of rubber, such as silicone rubber or natural rubber.
For natural rubber or EPDM, try using a specialist cyanoacrylate adhesive, such as ASI RP Series Cyanoacrylate Super Glue. This product provides strong adhesion for most substrates, but it is especially effective for rubber and plastic. If you are working with silicone rubber, you will need to use a primer, such as Permabond POP, before applying the adhesive. If flexibility is desired, Permabond 2050 cyanoacrylate works well.
Bonding Rubber to Other Substrates
Bonding two rubber surfaces together can be challenging enough, but, when you need to bond rubber to another substrate, the challenge can become even greater. When you need to glue rubber to plastic, metal, glass, or any other substrate, you need to consider the properties of each and your ultimate goal. While cyanoacrylate is the ultimate choice for many applications, it cannot be used on many plastics, as it can eat through the material.
When working with multiple substrates, an epoxy adhesive is often the best solution. While epoxies are not the best choice for bonding rubber to rubber, they do effectively allow you to bond rubber to other materials, including metal and glass. Fast-curing silicone compounds are also an option, especially for small projects.
Conclusion
When bonding rubber, it is important to use the right type of adhesive. Using the wrong type could result in damage to your substrates or prevent them from adhering together. Cyanoacrylate is one of the products of choice for bonding rubber to rubber, but it is not always effective.
Properly cleaning the surfaces to remove things like mold releasers and lubricants increases your chance of a successful bond, but sometimes a different product is needed. At Glue Gun, we stock numerous adhesives for a wide range of projects. Whether you are in need of a high-quality cyanoacrylate super glue, an epoxy, or a silicone adhesive, we have you covered. Contact us today or browse our website for the adhesive products you need for bonding rubber.