What are cataplasmic tests?

Cataplasm test - i.e. glue bond strength test

In the industrial sector and in repair and assembly works, the assessment of the durability of the adhesive joint is crucial to ensuring the longevity and safety of the structure. One of the precise tests that allow to assess the quality and resistance of the joint is the cataplasm test (climatic test) . Checking the durability of the joint using the cataplasm method provides information not only on the strength of the joint, but also on the behavior of the material in various environmental conditions. We present when and why it is worth conducting cataplasm tests, especially analyzing their application in relation to different materials and types of adhesives, including methacrylic adhesives.

What is the cataplasm test?

The cataplasm test involves exposing a bonded sample to a humid environment at an elevated temperature for a specified period of time. Typically, the sample is placed in a chamber at a temperature of 70 to 100 degrees Celsius, where there is high humidity. After the exposure, the material is subjected to strength tests to check whether the bond has retained its integrity and resistance. Such tests allow you to assess whether a given adhesive and material will be resistant to external factors that may weaken the bond.

Other commonly used names:  Adhesive strength tests, Adhesive ageing tests, Adhesive cataplasmic tests, Adhesive climatic test.

Why is it worth performing cataplasm tests?

Cataplasm tests are invaluable in assessing welds, especially in cases where the product or structure will be exposed to harsh weather conditions, such as high humidity, changing temperatures or chemical exposure. This solution is therefore particularly useful in the construction, automotive and furniture industries.

Adhesives that pass the cataplasm test guarantee that the joint will not be destroyed by the effects of temperature and moisture. This is extremely important in situations where the durability and safety of the entire structure depend on the joint.

 

 

 

Cataplasm tests on different materials

The durability of the bond depends on the type of material that is bonded with the adhesive. Here is an overview of how the cataplasm tests work on different substrates:

1. Wood

In the case of wood, cataplasm tests are extremely useful, especially in the production of furniture and structures exposed to changing environmental conditions. An adhesive bond that passes the cataplasm test on wood ensures that the final product will survive both heavy use and exposure to moisture. Polyurethane and epoxy adhesives show better results, while water-based adhesives often lose cohesion when exposed to a humid environment.

2. Metal

The cataplasm test for metal is particularly important when the bonded components will be used in environments with variable temperatures or high humidity, such as in outdoor structures. Epoxies, methacrylate and cyanoacrylate adhesives are often chosen for joining metal. After the cataplasm test, cyanoacrylate adhesives may show a weakening of the bond, while epoxies and methacrylate adhesives usually remain stable. Methacrylate adhesives are valued for their excellent adhesion to metals and resistance to harsh environmental conditions, as evidenced by positive results in cataplasm tests.

3. Plastics

Plastics, due to their chemical diversity, can react differently to the cataplasm test. Polyurethane, methacrylate and cyanoacrylate adhesives often exhibit high strength on plastics, although cyanoacrylate may weaken in some cases. Methacrylate adhesives are particularly good at joining plastics, offering both high mechanical strength and resistance to environmental conditions. The cataplasm test provides clarity as to whether the bond will withstand high temperatures and moisture.

4. Glass and ceramics

Glass and ceramics are materials with low tolerance to deformation, so the adhesives used to join them must be flexible and at the same time resistant to external factors. Silicone and hybrid adhesives work well in the cataplasm test, remaining durable despite exposure to extreme conditions. Epoxy adhesives, however, can crack, especially when the sample is heated intensively.

 

 

Different types of glues and their results after the cataplasm test

1. Epoxy adhesives

They are resistant to water and high temperatures, which means they pass cataplasm tests with high marks, especially when joining metal and wood. The disadvantage is their limited flexibility, which can be problematic in applications requiring high tolerance to deformation.

2. Polyurethane adhesives

They are characterized by very good resistance to moisture, which allows them to survive the cataplasm test even on water-sensitive materials such as wood. However, some types of polyurethanes may yellow or lose their properties when exposed to UV radiation.

3. Cyanoacrylate adhesives

They are ideal for quick bonding of metal and plastic, but their strength after the cataplasm test may be insufficient, especially after long-term exposure to moisture and heat. Cyanoacrylates can lose strength in high humidity conditions, so they are better used for interior applications.

4. Silicone adhesives

Silicones are an excellent choice where high flexibility and moisture resistance are required, which is why they pass cataplasm tests on glass and ceramics very well. The disadvantage is their longer drying time, which limits their use in some situations.

5. Methacrylic adhesives

Methacrylic adhesives combine high mechanical strength with a fast curing time, making them ideal for applications requiring a durable and resistant bond. They are particularly effective in joining metals and plastics, offering excellent adhesion even to difficult surfaces. After the cataplasm test, methacrylic adhesives demonstrate high resistance to moisture and temperature, maintaining the integrity of the bond. Their flexibility and ability to absorb stress additionally increase the durability of the bond in changing environmental conditions.

 

 

Advantages and disadvantages of cataplasm tests

Conducting cataplasm tests brings tangible benefits, but their limitations must also be kept in mind.

Advantages:

• Cataplasm tests allow the prediction of the durability and resistance of a weld under various conditions.
• They are universal and can be used to evaluate bonding on a variety of materials.
• They help you choose the right adhesive depending on the target operating conditions.

Defects:

• The tests are time-consuming and require specialized equipment.
• They may not take into account all environmental factors, such as the effects of UV radiation.
• The cost of performing tests can be high, which limits their use in smaller businesses.

Where to perform a cataplasmosis test?

We can perform these tests for you.

Here are the abbreviated conditions for the cataplasm test:

• Free tests: Samples measuring 100 x 25 mm (for metals, plastics, composites); for other materials consultation required.
• Overlap: 12.5 mm.
• Procedure: Plates are torn apart with a professional actuator, then subjected to cataplasmic tests.
• Support: Adhesive selection from scratch, comparison with other products.
• Minimum quantity of samples: 18-24 pieces to start with.

Check out our video and learn more: https://www.youtube.com/watch?v=4qhuFRev4uQ

 

Summary

Cataplasm tests are an extremely valuable tool that allows for a comprehensive assessment of the strength of a joint in difficult environmental conditions. Carrying out such tests is particularly justified when we expect the adhesives to be highly resistant to moisture and heat. Regardless of whether we are gluing wood, metal, plastics or glass, the cataplasm test will help us choose the right adhesive solution, thanks to which the joint will remain durable for many years.

Would you like us to perform such a test for free? - write to: sklep@ataszek.pl