Polymer materials testing and analysis

Utilizing the most modern analytical techniques, Perlast can provide detailed independant analysis of polymer materials.

This work takes a number of different forms:-

Chemical compatibility
Seal materials are often used in unique combinations of fluids over a wide variety of temperatures. Test facilities at Perlast allow chemical compatibility trials to be performed to address specific customer needs. Changes in physical properties for various materials can be examined and the most cost effective solution found.

Failure Analysis
A seal that has failed in an application is analyzed using various techniques to identify the cause and mode of failure. This often includes differentiating between thermal and chemical degradation and investigating other possible causes - such as mechanical failure, environmental stress, premature ageing, contaminants/inclusions and poor design. Perlast provides assistance in recommending alternative designs or materials.

Thermo-mechanical Evaluation
Using environmental chambers to test the physical properties of materials at actual or elevated operating temperature provides accurate results which are much more representative of actual applications.  The data is then used in FEA computer modeling to create accurate simulations of appropriate seal designs.

Thermal Analysis:

Differential Scanning Calorimetry (DSC)
DSC analysis depends upon comparing the exothermic and endothermic reactions of samples and a reference, as the sample and reference are heated through a defined heating regime. The technique enables the accurate determination of glass transition temperatures, crystallization and melting points and in the case of elastomers, cure characteristics.

This technique is valuable for failure analysis and compound development.

Thermogravimetric Analysis (TGA)
TGA analysis depends upon the accurate weighing of a sample as it is, heated, from – typically -25°C to 800°C. As the heating progresses, different components of the elastomer formulation ‘burn off’ thereby reducing the weight. A step-like pattern emerges which correlates quantitatively with the components of the formulation.

This technique is valuable for compound development, reverse-engineering, process control and failure analysis.

Infra-red Spectroscopy (FTIR)
FTIR involves passing an infra-red light through or impinging on a sample of material. The light gives up some of its energy, causing various molecular structures in the sample to vibrate, twist or stretch. The resultant light is then compared with a reference light stream and the result is represented as a characteristic plot of peaks.

This technique is helpful in ‘fingerprinting’ materials, failure analysis and compound development.

Explosive Decompression Testing
Explosive decompression damage of elastomer seals occurs when seals are under high pressure for some time and then rapidly de-pressurised. Gases absorbed into the elastomer rapidly expand causing the seal to rupture.

PPE’s advanced ED test equipment can pressurise seals of various geometries up to 10,000 psi and can decompress over any desired cycle or time, whilst at a temperature of up to 250°C. Using this equipment, compounds can be developed and tested to overcome this condition, with pressure, temperature and pressure release cycles simulating actual field operation, confirming the performance of seal types and grades before installation.