Adhesives & Sealants Testing and Analysis

An adhesive testing lab can evaluate both how an adhesive performs and why it performs that way.

Depending on the project, testing may include bond strength, peel or shear behavior, viscosity and rheology, curing behavior, thermal stability, chemical composition, surface contamination, and failure mode analysis.

For formulation or troubleshooting projects, performance testing can also be combined with chemical analysis to determine whether differences in resin chemistry, additives, curing agents, fillers, contamination, or processing may be contributing to the observed result.

The appropriate test depends on the adhesive, substrate, joint geometry, and application.

Common approaches include:

• Lap shear testing for structural adhesive joints and rigid substrates
• Peel testing for flexible materials, films, tapes, and laminates
• Tensile or pull-off testing for selected bonded systems and coatings
• Tack testing for pressure-sensitive adhesives
• Comparative bond testing before and after heat, humidity, water, or other environmental exposure

There is no single bond-strength test that is suitable for every adhesive system. The test method should match how the bonded product is actually used.

Yes. Tell us the material, the samples available and the decision you need to make. We will recommend a suitable starting plan.

We can still identify and characterize the submitted material. A specification, SDS, previous report or supplier document can provide useful context. If no reference is available, the report will focus on what can be established from the sample itself.

We provide chemical evidence and sample comparisons to support your internal decision. Final release criteria should be based on your validated specification, process and quality requirements.

Yes. Multiple samples can be compared within one project. Clearly label each sample and tell us which one is the approved or preferred reference.

No analytical method can guarantee detection of every possible component. Results depend on the material matrix, component level, available reference information and selected methods. We will explain the scope and limits before testing.

It depends on the material and analytical plan. Send us the sample information first, and we will confirm the recommended quantity before shipment.

Peel testing evaluates the force required to progressively separate a bonded interface, making it particularly useful for flexible adherends such as films, tapes, labels, and laminates.

Lap shear testing evaluates the load required to shear a bonded overlap joint and is commonly used for structural adhesives bonded to relatively rigid substrates.

The two tests measure different aspects of adhesive performance, so results should not be treated as interchangeable.

The first step is to determine where the failure occurred.

Three common failure modes are:

• Adhesive failure: separation occurs at the adhesive–substrate interface
• Cohesive failure: fracture occurs within the adhesive layer
• Substrate failure: the substrate fails before the adhesive bond

However, identifying the failure mode does not automatically identify the root cause.

Poor bonding may be associated with surface contamination, insufficient cleaning, low surface energy, incorrect surface treatment, incomplete curing, formulation changes, moisture exposure, aging, or adhesive–substrate incompatibility.

For this reason, adhesive failure analysis may combine mechanical testing with microscopy, surface analysis, chemical characterization, and comparison between good and failed samples.

Yes. Comparative testing before and after environmental exposure can help determine how temperature, humidity, water, or other service conditions affect bond performance.

If bond strength decreases significantly after exposure, further analysis can be used to investigate whether the change is related to:

• adhesive degradation
• moisture uptake
• plasticization
• incomplete cure
• loss of interfacial adhesion
• substrate corrosion or surface change
• formulation differences

For failure investigations, comparing the aged sample with an unaged reference often provides more useful information than testing the failed sample alone.

Initial bond strength represents only one part of adhesive performance.

Two adhesives may show similar strength under laboratory conditions but differ in:

• heat resistance
• humidity resistance
• flexibility
• creep resistance
• curing behavior
• viscosity and application behavior
• chemical resistance
• long-term aging
• interfacial compatibility

This is why adhesive evaluation often requires a combination of performance testing, material characterization, and formulation analysis rather than relying on one strength value.

Yes. Supplier and batch comparison is a common application of adhesive testing.

A comparison may evaluate:

• bond strength
• peel or shear behavior
• viscosity and rheology
• curing behavior
• thermal properties
• chemical composition
• filler or additive differences
• contamination or unexpected components

Testing a known-good reference alongside a new or abnormal sample can help identify whether the difference is mainly related to formulation, raw materials, processing, or application conditions.