Papers by Keyword: FTIR-ATR

Abstract: Formic acid, commonly used in bioprocesses of cellulosic polymeric materials, has been considered for the treatment of cellulose-based textile. Therefore, different concentrations of formic acid (10, 20, 30, 40, and 50 g L^-1) were used to treat cotton (CO) and viscose (CV) fabrics to improve their properties. Weight variation, tensile strength, stiffness, drape coefficient, crease recovery angle, and vertical wicking of the treated substrates were assessed. Fourier transform infrared spectroscopy attenuated total reflection (FTIR-ATR) analysis confirmed the acid hydrolysis process of the cellulosic substrates treated with formic acid solutions. Formic acid solutions with concentrations equal to 30 g L^-1 and 40 g L^-1 are the most adequate to treat the CV and CO fabrics, respectively. In addition, the fabrics treated under optimal conditions were dyed with the reactive dye Levafix Blue CA. The dyeing properties were assessed through colour absorption coefficient and scattering coefficient (K/S) values. A clear improvement in the fastness and dyeing performance of the treated substrates was observed. Finally, the antibacterial properties of the treated substrates were evaluated, for the bacteria Escherichia coli and Staphylococcus aureus. It was found that only cotton substrates treated with a 40 g L^-1 formic acid solution could be classified as weak decontaminants against S. aureus bacteria.

Abstract: Spectroscopy Fourier Transform Infrared (FTIR) – Attenuated Total Reflectance (ATR) used to study the surface of polymeric materials on polymeric substrates using a sensitive technique for chemical profiling, study of reflection spectroscopy, and a non-invasive. In this study we will investigate of Polytetrafluoroethylene (PTFE) deposition in carbon composite paper without damaging its structure by FTIR-ATR. Carbon composite paper was prepared by mixing the carbon material from coconut fiber and polymer binder in xylen as solvent, casted on glass substrate, and then rolled to make a sheet. Coating process was done by dipped the carbon composite paper in the PTFE suspension with different content of 10 wt%, 20 wt% and 30 wt% for 30 minutes and dried at room temperature for one night and heated at 150°C for 30 minutes, and finally heated at 350°C for 30 minutes to melt the PTFE. All samples were analyzed by using FTIR-ATR and SEM-EDS. Deposition of PTFE with different content in carbon composite papers could be observed by FTIR-ATR. The peaks located at near 1205 cm^-1 and 1154cm^-1 with different intensity for each PTFE contents. FTIR-ATR could be used as a pre-detection method of PTFE deposition in carbon composite paper before using SEM-EDS, because FTIR-ATR would be reflected at the highly reflective surface.

Abstract: In this study the effect of trimethylopropane triacrylate (TMPTA) content as a crosslinking agent on curing properties of UV-cured pressure sensitive adhesives (PSAs) was investigated. The curing properties were studied using gel fraction determination, photo-differential scanning calorimetry (photo-DSC) and Fourier transform infraredattenuated total reflection (FTIR-ATR) spectroscopy. Gel fraction sharply increased after expose to UV irradiation and increased with increasing TMPTA content. Moreover, the addition of TMPTA as crosslinking agent induced an earlier onset of auto acceleration and relative concentration of the C=C was not zero because they were trapped in the PSAs network.

Abstract: Since silicon will ultimately face physical limitations, germanium and III-V materials, such as Ga, GaAs, InGaAs, are being extensively investigated for their high electron and hole mobility advantages. Prior to implementing germanium or III-V materials, it is believed that SiGe with high Ge concentration will be applied for channel materials in pMOS devices with high-k and metal gates in order to simultaneously adjust the work function and to increase the hole mobility. However, introduction of new channel materials leads to new challenges and substantial changes in the FEOL process flow.

Abstract: This work is to examine ways to chemically modify soy proteins flours and analyze the results and determine the adhesive performance. Reaction with acetic anhydride converts amine and hydroxyl groups to amides and esters, respectively that are less polar and can make the adhesive more water resistant.The succinic anhydride reacts with these same groups but the products have terminal carboxylic acid groups that can react with the polyamidoamine-epichlorohydrin (PAE) resin that is used to cross-link the soy adhesives for improving bond strength. The attenuated total reflectance infrared spectroscopy (ATR-IR) is used to examine changes in the soy flour in going from unmodified to acetylated and succinylated state.