Med Thermomechanical Analysis (TMA) examines the properties of the material at different temperatures and times when applying a pressure. Viscoelastic materials may have changes in volume that are related to shrinkage, expansion, swelling and softening. The instrument performs the measurement by applying a force (F) to the material while the temperature changes with the instrument recording the change in length (Δl) that occurs. Below are some examples of information that you get by using thermomechanical analysis of materials.

Glass transition

Glass transition of materials can be studied by thermomechanical analysis as it is the point where the material changes from soft to hard or vice versa. With TMA you can determine the glass transition of materials with a high proportion of fillers, which otherwise can be difficult with other techniques such as DSC.

Coefficient of thermal expansion

The coefficient of thermal expansion may be important to know depending on what a material is intended to be used for.

Differences in softening temperatures

Differences in the temperature at which a material is softened can be studied after the influence of a process or aging.

Creep behaviour for elastomeric materials

The behavior of elastomeric materials is often a property that needs to be investigated. This property is important when it comes to elastomers intended to be used for different types of seals. A good seal should exhibit as low viscous flow as possible.

Thermal stability

Thermal stability can be evaluated for different materials using TMA. One can investigate, for example printed circuit boards that need to have good thermal stability. Another example is insulating coatings for electronic components that should be thermally stable.

Gelation times

Components that are cured by a reaction to their final shape reach after a certain period the so-called gelation. After this, the material can no longer be formed and it is therefore important to keep an eye on this time before you can process your material. This can be measured using TMA.

Shrinkage

TMA is a good instrument for measuring shrinkage of various materials, such as plastic films. Here you can also assess the anisotropic behavior of the materials.