RMS Foundation
Bischmattstrasse 12
2544 Bettlach
Switzerland
Phone +41 32 644 2000
METHODS
Fourier Transform Infrared Spectroscopy
(FTIR)
FTIR spectroscopy (Fourier transform infrared spectroscopy) is an analytical method used to identify chemical (usually organic) compounds and to investigate their molecular structure. Infrared light is sent through a sample and the absorption of the light is measured based on the excitation of molecular vibrations. Each chemical bond in a molecule absorbs infrared light at specific wavelengths, creating a unique "spectrum" that serves as a fingerprint of the substance.
FTIR microscopy combines FTIR spectroscopy with a microscope to obtain chemical information at the microscopic level. This technique also allows small samples (in the um range) to be analyzed (such as particles or defects in polymers).
Another possibility is chemical imaging. The surface of a sample is sequentially irradiated with infrared light and the absorbed wavelengths are measured. This allows detailed chemical maps to be created that visualize the distribution of different compounds on a sample surface. This is particularly useful in materials science or biology.
According to which standards do we test?
Whenever possible, we carry out our testing services in accordance with or based on these international standards:
- ASTM E1252
- ASTM F1581
- ASTM F2102
- ISO 13779-6
Which devices do we use?
- Bruker FTIR Microscope LUMOS
For which material tests do we use this method?
We use Fourier Transform Infrared Spectroscopy (FTIR) for the following material tests, among others:
- Identification of organic compounds or their composition
- Identification of organic particle contamination
- Determining the functional groups of calcium phosphate phases
- Determination of the oxidation index of polyethylene
- Chemical characterization of surfaces
- Determination of the dichroic ratio (verification of securitiy features)
- Surface cleanliness (clock works, electronic boards, etc.)
- Ageing of polymers
What you should know about this method?
For which materials is the method suitable?
- Solid, liquid and gaseous samples
- Organic (especially polymers) as well as partly inorganic compounds
- Particles with a diameter of approx. 5 um and more.
Which materials can be analyzed quantitatively?
The intensity or rather the integral of an IR signal is proportional to the concentration of the corresponding functional group (e.g. an ester group). Although FTIR spectroscopy is mostly used to identify a specific compound, any IR active functional group can also be quantified.
How much sample material is required?
For macroscopic samples:
- approx. 1 - 5 g for solids
- approx. 10 mL for liquids
For microscopic samples
- Surface area of > 5 um for solids + liquids
Are the methods accredited?
- Yes, most services are accredited.
- Quantitative measurements of individual samples can be validated with some additional effort.
