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Ethylene propylene diene monomer rubber is used as flexible thermal protection for rocket engines, as well as in blends with polychloroprene, which can be applied in the aeronautical sector, and with great potential in the defense sector. However, there is not a considerable number of studies considering both polymers as a blend. In general, elastomer content quantification in blends is done by more complex instrumental methods. When performed by Fourier transform-infrared spectroscopy, the conventional transmission mode is used, usually without including the developed methodology error. Therefore, the Fourier transform infrared spectroscopy (FT-IR) methodology is proposed using the universal attenuated total reflection mode, with sample treatment (pyrolysis) to determine polychloroprene content in the mixture with ethylene propylene diene monomer. In accordance with the infrared spectrometer precision limits and rubber blends studies data found in the literature, the methodology error analysis shows a value close to 2%. In addition, it has the advantage of being a less complex methodology. This actual study uses a simple FT-IR analytical tool, scarce, especially for the rubber research community, to determine the content of rubber minor phase within the major phase. It is valuable in weapons reverse engineering, aiming at the knowledge of new thermal protections.

Nitrocellulose (NC) is a polymer of great interest in the aerospace and paint/coating fields. However, there are gaps regarding quantitative analysis. Fast and accurate methodologies for the quality control of raw materials are limited. In this context, the determination of the nitrogen content in NC and the contents of different acrylic/styrene components in formulations with NC were assessed. The applicability of non-conventional Fourier transform infrared spectroscopy (FT-IR) techniques, using the universal attenuated total reflection (UATR) mode, in the medium infrared (MIR) region and of the transflectance in the near infrared region (NIRA) were evaluated. For nitrogen determination, FT-MIR/UATR analysis proved to be the most accurate methodology. For the analysis of acrylic/styrene components in NC, it was possible to determine, with good precision, the contents of most samples by FT-MIR/UATR and FT-NIRA.

Ethylene propylene diene monomer rubber is used as flexible thermal protection for rocket engines, as well as in blends with polychloroprene, which can be applied in the aeronautical sector, and with great potential in the defense sector. However, there is not a considerable number of studies considering both polymers as a blend. In general, elastomer content quantification in blends is done by more complex instrumental methods. When performed by Fourier transform-infrared spectroscopy, the conventional transmission mode is used, usually without including the developed methodology error. Therefore, the Fourier transform infrared spectroscopy (FT-IR) methodology is proposed using the universal attenuated total reflection mode, with sample treatment (pyrolysis) to determine polychloroprene content in the mixture with ethylene propylene diene monomer. In accordance with the infrared spectrometer precision limits and rubber blends studies data found in the literature, the methodology error analysis shows a value close to 2%. In addition, it has the advantage of being a less complex methodology. This actual study uses a simple FT-IR analytical tool, scarce, especially for the rubber research community, to determine the content of rubber minor phase within the major phase. It is valuable in weapons reverse engineering, aiming at the knowledge of new thermal protections. [ABSTRACT FROM AUTHOR]

Instrumental techniques such as Fourier Transform Infrared Spectroscopy (FT-IR) constitute well-studied methodologies for polymer characterization, including polymeric fibers. However, a relatively short number of scientific publications involve the characterization of commercial Poly [(4-hydroxybenzoic)-ran-(2-hydroxy-6-naphthoic acid)] (Vectran™) fiber and its surface species. The majority of the published infrared studies uses the medium infrared region (MIR) associated to the Attenuated total reflection (ATR) method. In this scenario, this short review addresses the characteristics of Vectran™ fiber, sample depth data of each FT-IR spectrum mode, reflection and photo-acoustic spectroscopy (PAS), including near infrared (NIR) analysis. This paper addresses also researches on the characterization of Vectran™ by several FT-IR analysis conditions aiming to contribute to future studies. This brief review deals with methodologies developed in the last decade and published by several scientific research groups, emphasizing studies conducted in the last five years. A critical assessment and trends are also included. • The characterization of Vectran fiber has been little explored, which offer opportunities for further research. • ATR (Ge), UATR, FT-IR microscopy and PAS are best suited for fibers and its surface species analysis. • Few studies have been found that use them to analyze Vectran behavior and its characteristics. • The existing gap in this scientific field related to FT-IR techniques applied to the analysis of the Vectran fiber surface. [ABSTRACT FROM AUTHOR]

Nitrocellulose (NC) is a polymer of great interest in the aerospace and paint/coating fields. However, there are gaps regarding quantitative analysis. Fast and accurate methodologies for the quality control of raw materials are limited. In this context, the determination of the nitrogen content in NC and the contents of different acrylic/styrene components in formulations with NC were assessed. The applicability of non-conventional Fourier transform infrared spectroscopy (FT-IR) techniques, using the universal attenuated total reflection (UATR) mode, in the medium infrared (MIR) region and of the transflectance in the near infrared region (NIRA) were evaluated. For nitrogen determination, FT-MIR/UATR analysis proved to be the most accurate methodology. For the analysis of acrylic/styrene components in NC, it was possible to determine, with good precision, the contents of most samples by FT-MIR/UATR and FT-NIRA. • There are gaps regarding quantitative analysis of Nitrocellulose (NC) in the aerospace and paint / coating fields. • Non-conventional reflection and reflectance infrared techniques are recommended for the quantification of nitrogen and acrylic/styrene contents in NC systems. • For nitrogen determination, FT-MIR/UATR analysis proved to be the most accurate methodology. • For the analysis of acrylic / styrene components in NC, it was possible to determine, with good precision, the contents of most samples by FT-MIR / UATR and FT-NIRA. • Non-conventional FT-IR/UATR in the MIR region and the transflectance in the NIR region was evaluated. [ABSTRACT FROM AUTHOR]