Case Histories

Rapid Analysis of Flame Retardant (FR) Systems

Complete Raman Spectrum
Partial Raman Spectrum

We have developed a method using rapid non-destructive Raman spectroscopy for analysis of plastic enclosure materials containing FRs and other additives. The system is portable and therefore suitable for use in the field. This system has a wide range of applications including polymer recyclate analysis, polymer identification and qualification, and analysis and qualification of FRs and other additives either as separate samples or existing within the polymer matrix.

The spectra provide us with reliable identification of the FR molecular composition, a clear advantage over more commonly used techniques which only provide elemental data. Measurement time is typically fast, and in some cases in which a strong Raman signal is present, only a fraction of a second is required.

The system is also under development for analysis of plastics containing dark pigments such as carbon black. Some recent tests with a new experimental set-up have yielded promising results for plastics such as ABS and HIPS containing carbon black, a material which has up until now prove presented difficulties in spectroscopic measurement due to the high absorption of the carbon component and other factors.

This method relies on spectral absorption to characterise materials. However, in contrast to conventional analysis, which relies on discrete absorptions, TranSpec™ uses all spectral information over a wide wavelength range to analyse organic molecules, such as natural and synthetic polymers and additives, to provide a “materials fingerprint” sensitive to the local molecular environment.

Transformer Insulation Assessment

Inspection of Transformer

PCA and PLS analysis, implemented in the TransChem™ software, extracts correlation between spectral features and sample properties, in this case degree of polymerisation (DP), and indicator of paper degradation. Prediction of DP can be achieved to an accuracy of 50 units using this method.

Key Steps

  1. Obtain calibration data from samples in laboratory
  2. Construct calibration models
  3. Take measurements on site
  4. Validate models and predict sample properties

More detailed information is available to download.

Enclosure Plastics Assessment

Cluster analysis – implemented in the TransChem™ software – groups similar materials together, allowing grade information to be extracted. The figure shows the variation observed in PET bottles from many different suppliers - this includes colour information, an important parameter.

The information in these data is rich, and provides more than just identity. It can be used, through the inherent correlations between molecular structure and physical properties, to qualify the materials without doing tedious and imprecise “first principles” calculations.

The method is “trained” on characterised library samples for the materials of interest, then validated.

Key Steps

  1. Obtain polymer spectral database
  2. Polymer type discrimination
  3. Polymer property/quality determination

More detailed information is available to download.