Best Glue for Rubber

How to Select the Best Glue for Rubber

Today, rubber accounts for a large percentage of household wares and other appliances we use in everyday life. Due to how popular and common rubber is today, people rarely care about the differences. Many people wrongly assume that all rubbers are the same with the same properties and quality. However, there are different types of rubber available today with unique properties and characteristics.

Rubber is one of the materials that are notably difficult to glue together. This is the reason most people choose to discard and replace instead of trying to repair rubber items. 

Rubber glue comes in many different types with unique properties and requires physical, thermal, electrical, and chemical properties. The glue you use for each type of rubber must also satisfy the properties of the rubber you want to glue. Therefore, there are different things you need to put into consideration when selecting glue for rubber. 

Consider the type of rubber 

There are different types of rubber available in the market today. Some of these rubbers are very common while others are scarce to find. The most common types of rubber in the market today are nitrile, butyl, natural rubber, silicone, and EPDM rubber. There are numerous others you can come across. However, these are more common and make up a vast majority of what we see around today. They can be found in inner tubes, gloves, gaskets, hoses, boots, etc. 

Understanding the type of rubber you are working with is the best step to selecting the right glue for it. While some glue will work best for the natural robber, others are best for other kinds of rubber. 

One of the ways you can identify the type of rubber is by using the product’s recycle logo. The recycle logo is something that a lot of us already know. Whenever you see three arrows in form of a triangle, that is what we refer to as the recycle logo. When you look closely, this logo always contains a number or a code that tells one type of plastic apart from the other. The primary aim of this is to ensure the proper recycling of plastic. Generally, there are a total of eight recycling codes for rubber, which gives you a clue to the exact type of rubber. 

 However, these codes are essential to telling you about the kind of rubber you are dealing with and provides a clue to the best type of glue to use. Once you figure out the kind of plastic you have, picking the right glue is easier. Rubber is usually labelled in categories 1,2,3,4 and 5. Items in category one are often the most difficult if not impossible to glue. Other plastics carry the numbers 6 and 7 respectively, which are rare to come by. 

Consider the curing time and method

When choosing the best glue for rubber, it is essential to also consider the curing time of the glue. Many people make the mistake of failing to read the direction of use before using glue. While some may take a shorter time to cure, others will take up to two days to properly cure. 

To enjoy the maximum benefit:  Ensure you understand the direction of use before using the glue. If the direction states that you need to cure for 48 hours, it is vital to follow the direction. 

Consider where you will be using the rubber 

While many people overlook this point, it is very essential if you want your glue to bond well using glue under the wrong weather conditions can affect the performance of the glue, same as the wrong use. 

Some glue is water-resistant and can work well under wet conditions. However, there are also a good number of glue that is not water-resistant, and using them in wet conditions can affect their performance. 

Preparing Rubber before Gluing

No matter the rubber type you are working with, taking the time to prepare the plastic is essential for good bonding.

Begin by using a solvent to remove all forms of additives like grease, mould, and other types of lubricants. The use of isopropanol can help get rid of all kinds of slip additives from the plastic. 

You can also use acetone for the same purpose. However, it is not advisable to do so since acetone may be too powerful for certain types of rubber.  

What Type of Glue is best?

Are you still wondering what kind of glue is best for your rubber? We generally recommend that you select glue following the type of plastic that you want to glue. 

In general, we often recommend the use of a cyanoacrylate instant adhesive for your rubber. Cyanoacrylate glues are k own by the generic name super glue and cure very fast. The importance of this is that you will know instantly is your glue works fine for the plastic or not. 

Apply a thin strip of glue on the surfaces that you want to glue together and squeeze both surfaces together. If after six seconds bonding does not occur, know that you may be dealing with the more difficult types of rubber which are the natural rubber or the silicone rubber. 

 When you are working with natural rubber or silicone, it is essential to use the appropriate glue to avoid running into problems. 

For natural rubber or EPDM, you should consider using special cyanoacrylate glue like the Loctite AA324 Speebonder Acrylic Glue or the ASI series that are both specially formulated for bonding natural rubber. If you are working with silicone, we already stressed the use of a primer before now. Using a primer on the bonding surface will help prepare the surface for bonding.

Bonding Rubber to Other Surfaces

Bonding Rubber to other rubber can be tough. However, the main problem arises when you need to bond rubber to other substrates. When trying to bond plastic to other materials like wood, glass, bricks, metal, etc. You have to consider the properties of both materials and also the goal you wish to achieve at the end of the day. 

When working with multiple surfaces, it is best to work with epoxy glues. Naturally, epoxy glue may not work well for bonding rubber to rubber, but it does an effective job for bonding rubber to another surface.