Fourier Transform Infrared Analysis

 

SEM Lab, Inc. supports routine FTIR Analysis of plastic parts to compare lot-to-lot variation in the molecular structure of the polymer. FTIR spectra are affected by mix-ratio, degree-of-cure, contamination, and a range of other factors that are important for quality control.

FTIR (Fourier Transform Infrared) analysis provides spectral information that is essentially a molecular fingerprint for organic, polymeric, and in some case inorganic materials. This technique is extremely useful for identifying base polymer compositions and organic contaminants. The FTIR spectrum of the unknown material can be compared for “best matches” with libraries of spectra that have been cataloged for known materials.

An example of an FTIR spectrum for Poly(oxymethylene) or POM or DelrinTM (DuPont trademark) is shown as Fig. A. The x-axis is wave number (cm-1), which is the inverse of wavelength (cm). The y-axis is absorbance normalized on a scale of 0 – 1 where 1 = no absorption and 1 = maximum absorption.FTIR spectrum for Poly(oxymethylene) or POM or DelrinTM

 

Fig. A – FTIR spectrum for Poly(oxymethylene) or POM or Delrin TM.