Fourier Transform Infrared Spectroscopy FTIR is a powerful analytical technique used to identify different functional groups present in a polymer sample. It works by measuring the absorption of infrared radiation by the sample, which causes molecular vibrations in the functional groups. Each functional group has a unique vibrational frequency, which corresponds to a specific absorption peak in the FTIR spectrum. By analyzing the positions and intensities of these peaks, chemists can identify the functional groups present in the polymer and obtain valuable information about its structure and composition.Here's how FTIR can be used to identify different functional groups in a polymer sample and assist in its characterization:1. Sample preparation: The polymer sample is prepared for analysis, either by creating a thin film or by mixing it with an appropriate matrix such as potassium bromide to form a pellet.2. Infrared radiation: The prepared sample is exposed to a broad range of infrared radiation wavelengths. The sample absorbs specific wavelengths corresponding to the vibrational frequencies of its functional groups.3. Interference pattern: The transmitted or reflected radiation from the sample creates an interference pattern, which is recorded by a detector.4. Fourier transformation: The interference pattern is converted into an absorbance spectrum using a mathematical process called Fourier transformation. This results in a plot of absorbance or transmittance versus wavenumber or wavelength .5. Peak identification: The peaks in the FTIR spectrum are analyzed to identify the functional groups present in the polymer. Each functional group has characteristic absorption peaks at specific wavenumbers, which can be compared to reference spectra for identification.6. Polymer characterization: The information obtained from the FTIR spectra can be used to characterize the polymer in several ways, including: a. Chemical composition: Identifying the functional groups present in the polymer provides insight into its chemical composition and structure. b. Molecular weight: The intensity of certain peaks can be related to the molecular weight of the polymer, providing information about its size and distribution. c. Degree of crystallinity: The relative intensities of peaks corresponding to crystalline and amorphous regions in the polymer can be used to estimate its degree of crystallinity. d. Copolymer composition: In the case of copolymers, the relative intensities of peaks corresponding to different monomer units can be used to determine the copolymer composition. e. Chemical modifications: FTIR can also be used to monitor chemical modifications, such as crosslinking or degradation, by observing changes in the spectra over time or under different conditions.In summary, Fourier Transform Infrared Spectroscopy FTIR is a valuable tool for identifying functional groups in polymer samples and obtaining information that can assist in their characterization. By analyzing the FTIR spectra, chemists can gain insights into the chemical composition, molecular weight, degree of crystallinity, copolymer composition, and chemical modifications of the polymer.