A systematic study using design of experiments was applied in order to map out the thermal stabilization of electrospun polyacrylonitrile mats and to investigate how oxidation and cyclization reactions are affected by rate, temperature, and time in an oxidative environment. Cyclization indexes were estimated by a simple methodology based on differential scanning calorimetry (DSC) and Fourier transform infrared spectroscopy data. Values of enthalpy and relative intensities of bands assigned to CN and CN bonds were used on calculation. The statistical planning applied in this study was important to show that not always longest treatment is effective to stabilize polyacrylonitrile, but also samples obtained in less than 3 h presented low values of exothermic peak on DSC, values of cyclization indexes near to 90%, both from DSC and Fourier transform infrared spectroscopy techniques, reduced weight loss in thermogravimetric analysis and O/C ratio higher than 10% by X‐ray photoelectron spectroscopy, that are appreciated characteristics to a precursor of high‐performance carbon materials. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017, 134, 45458.

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The surface of vulcanized ethylene propylene diene terpolymers (EPDM) was modified by Ar and N2, microwave generated plasma in order to improve adhesion properties. Surface modification was characterized by universal attenuated total reflectance Fourier Transform Infrared (UATR/FT-IR), because it presented lower interference of ingredients of EPDM formulation when compared with other techniques used for the attenuated total reflectance (ATR) to different crystals (ATR/KRS-5 and ATR/Ge). Oxygenated groups were introduced on the surface after treatments which were formed when the activated surface was exposed to the plasma gas. In treatments with nitrogen, oxygen groups and probable nitrogen groups were formed on the surface and could be identified by FT-IR. Reduction in the measurement of the contact angle and an increase in the work of adhesion and in the peel strength (EPDM X Polyurethane (PU)) were observed after the treatment resulted in the improvement of the adhesion properties of the modified surface.

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Fourier transform infrared spectroscopy techniques, associated or not to others, are a well-studied subject used for characterizing polymers/energetic materials that have been employed mainly in aerospace industries. However, the infrared analyses are usually qualitative and performed using the mid-infrared. This paper discusses the Fourier transform infrared spectroscopy qualitative and quantitative methodologies, coupled or not with thin layer chromatography and thermogravimetric analysis, for characterization of aerospace polymer systems, in some cases, using mid-infrared, near-infrared and far-infrared regions, by traditional accessories and the latest generation spectra mode, universal attenuated total reflection. This short review was made based on methodologies developed during the last two decades and published by many scientific and industrial research groups, emphasizing studies usually carried out in the last five years. A critical assessment and future trends were included.