Papers by Keyword: FTIR

Abstract: This study dealt with the synthesis and characterization of thin transparent conducting films (TCF) from cellulose acetate (CA) blend and polyaniline (PANI). CA was produced from the pulp of abaca hybrid 7. CA-PANI films with different PANI loadings (0, 0.125, 0.25, 0.50, 1.0 and 2.0%) were produced using solvent casting method. Chemical transformations were analyzed using Fourier Transform Infrared (FTIR) spectroscopy. The conductivity was measured using the Four-Point Probe Test. Morphological characterization was done using Scanning Electron Microscopy (SEM). The transparency of the films was determined using UV-Vis Spectroscopy. FTIR spectra proved the embedment of PANI in the CA matrix. It was found that increasing the PANI loading increases the conductivity of the films but up to a certain limit. The highest average conductivity at 2.0264 x 10^-5 S/m was observed in CA-PANI films with 0.50% PANI loading. SEM images revealed that conductivity is a function of PANI loading by forming networks. Further addition of PANI (1.0 and 2.0%) resulted to decreased conductivity due to agglomeration. Transparency, on the other hand, is negatively affected by PANI loading.

Abstract: Pineapple Leaf Fiber (PALF)-reinforced polypropylene (PP) based composites were prepared successfully by conventional compression molding technique. Different percentages (25,30,35, 40 and 405% by weight) of fiber were used to prepare composites. Tensile Strength (TS), Tensile Modulus (TM), Elongation at Break (Eb %), Bending Strength (BS), Bending Modulus (BM) and Impact Strength (IS) were evaluated. The 45 wt% PALF/PP composite exhibited an increase of 132% TS, 412% TM, 155% BS, 265% BM, and 140% IS with respect to the matrix material (PP). Fourier Transform Infrared (FTIR) Spectroscopy was employed for functional group analysis of PALF/PP composites. For all percentages of fiber, the composites demonstrated lower water uptake. The fabricated composites were immersed in alkali solution (Sodium hydroxide solution, 3%, 5% and 7% by weight) for 60 min and showed low TS, TM and Eb% compared to control composites.

Abstract: Cross-linked polyethylene (XLPE) as insulation material has been widely used in the manufacturing of medium and high voltage cables for its excellent physical, chemical, mechanical and electrical properties. However, as cable insulation, the XLPE will degradate under service conditions, such as thermal oxidative degradation, mechanical treatment, operating environment etc. In this paper, the closed cable loop had been heated for 7 days by induced current of 1000A, and several diagnostic measurements had been adopted to characterize the performance of XLPE. Firstly FTIR has been conducted on different bending degree cable samples in order to reveal the effect of mechanical treatment on the content changes which occur in XLPE insulation layers. DSC analysis showed the effect of cooling process on the shoulder melting peak temperatures. In the last part, microstructure of the insulation of high current bending XLPE cable was studied. The results showed that the properties of the bending cable after heating by the high current changed a lot and the degree of bending also has an effect on the performance of the cable.

Abstract: The influence of neem leaf extract on corrosion inhibition of mild steel in 0.1 M HCl solution was studied using the weight loss method. Neem leaf extract which contains the double bond, carbonyl groups, and aromatic rings functional group as shown by the GCMS, phytochemical test, and FTIR analyses is one of the good natural plant extract that can be used as corrosion inhibitor. The weight loss on surface of mild steel at various inhibitor concentrations was determined. The highest inhibition efficiency of 93.24% was achieved using the neem leaf extract as corrosion inhibitor. Adsorption mechanism was investigated using Langmuir, Temkin, and Freundlich isotherms. Inhibitor adherence on the mild steel surface was spontaneous with the negative Gibb’s free energy value obtained. The mixed type adsorption mechanism (physisorption and chemisorption) is proposed for the inhibitor adsorption on mild steel surface. The inhibitor was adsorbed on the mild steel surface through adsorption of the phytochemical components on the surface of mild steel which protects the metal surface from corroding. The corrosion rate decreases from 0.001 to 0.0002MPY with increase in inhibitor concentrations and exposure time.

Abstract: Controlling the hydration rate of cement can influence the properties of cement hydrates. Many commercial cement retarders are mainly adopted for slowing down the rate of cement hydration. In this study, the surface of the cement particles was modified by an organic sulfoxide to retard the rate of cement hydration. The organic sulfoxide, octyl phenyl sulfoxide (OPS), was firstly synthesized by mixing 1-dodecanethiol with aryl iodide to produce organic sulfide, and then organic sulfide was oxidized to the corresponding sulfoxide. The organic sulfoxide was identified by Nuclear Magnetic Resonance Spectroscopy (NMR). Hydrates of cement and cement modified with OPS were characterized by Fourier Transform Infrared Spectrometer (FTIR), Optical Microscope (OM), Scanning Electron Microscope (SEM) and powder X-Ray Diffraction (pXRD). Experimental results showed that OPS successfully reduced the rate of cement hydration and had positive effect on the long term microstructures of the harden cement paste.

Abstract: Novel and highly effective polyethylene oxide (PEO) based composite electrolytes were prepared by combining the graphene nanoplatelets (GR) and multiwall carbon nanotubes (MWCNT) for the application as solid polymer electrolyte. MWCNT and GR were used as reinforcing filler and as electrical conductivity enhancement agent. Dispersions in N,N-dimethylformamide (DMF) of MWCNT and GR within the PEO matrix were prepared. DMF are featured by high electron-pair donor number and low hydrogen-bonding parameters, therefore DMF is considered a standard for liquid-phase exfoliation of MWCNT and GR. In our study, the MWCNT and GR solutions were tip sonicated using an ultrasonic processor, operated at 80% amplitude. A pulse-mode (cycle of 0.5 s) sonication was used because of the system relaxation role for the off phase, allowing a higher cavitation intensity and lower heat generation to be reached. Subsequent heat pressing was applied to obtain thin solid PEO composite electrolytes. Analyses of the experimental and theoretical density of prepared solid PEO composite electrolytes are calculated and discussed. GR and MWCNT functionalization effect on void content of polymer composites is evaluated. FTIR analysis was carried out to further investigate the effect of fillers content. The SEM results showed that surface of electrolyte film became rougher after the addition of MWCNT and GR. It is concluded, that the higher is filler fraction, the lower is void content and greater is composite density.

Abstract: The use of hydroxyapatite coatings is limited by their inferior mechanical properties such as brittle nature, low wear resistance, abrasion, fatigue, and hardness. This ultimately leads to the wear and early rupture of the hydroxyapatite coating on the implant. The main objective of this study is to improve the mechanical properties of hydroxyapatite by using additional reinforcement material such as alumina (Al₂O₃). The HAp powder has been reinforced with 15wt% Al₂O₃ and its effect on the properties of HAp coatings has been studied. The HAp and HAp +15 wt% Al₂O₃ coatings were deposited on AISI 304 L SS substrates using the plasma spraying technique. The morphology of the coatings developed was characterized using SEM/EDX, XRD, and FTIR techniques. The corrosion resistance studies have been performed on uncoated and coated samples and found that HAp coated samples show superior resistance against corrosion (I_Corr = 0.538 μA) than uncoated (I_Corr = 3.550 μA) and HAp+15 wt% Al₂O₃ coated (I_Corr = 1.440 μA) samples when electrochemical corrosion studies were performed in Ringer’s solution. Surface roughness and microhardness were found to increase with the addition of Al₂O₃. Crystallinity (%) of the HAp coatings and HAp+15 wt% Al₂O₃ coatings increases after the corrosion testing.

Abstract: Natural ferrite oxide nanoparticles (NPs) embed with tellurite glasses ((89-x) TeO₂-10ZnO-1Er₂O₃-(x)Fe₃O₄, (x = 0 – 0.8 mol %)) were prepared by conventional melt quenching method to study the influence of the Fe₃O₄ NPs concentration on the stuctural properties of the glass. Studies on these glassy materials characterized by X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR) and RAMAN spectroscopic measurements are presented. It is observed that the amorphous nature of the glass is confirmed by x-ray diffraction. The FTIR studies support the formation of Te-O-Fe linkages. The FTIR spectra reveal modification in network structures evidenced from vibrational wave-number shifts of TeO₄ and TeO₃ structural units. Raman spectroscopy have been manipulated to observe the structural modification of [TeO₄] trigonal bipyramidal structural unit.

Abstract: Conductivity of sodium based solid electrolyte xNaI-(100 - x)NaN(CN)₂ with various compositions (0 ≤ x ≤ 70) were investigated by Electrochemical impedance spectroscopy (EIS) method in order to determine the conductivity value. Maximum conductivity of 10^-4 S cm^-1 was obtained for sample with 10 wt.% NaI. The improved conductivity could be due to presence of dicyanamide as an anionic-bridging ligand compound that provided conducting pathway for rapid Na⁺ ion conduction. The binary sodium solid electrolyte system was prepared by ball milling method with 200 rpm for 2 hours in order to promote ultra-fine size reduction and introducing defects in the crystal structure thus assisting rapid ionic mobility via hopping. Results obtained from Fourier transform infrared spectroscopy (FTIR) characterisation showed some changes in infrared spectrum peak appearance within wavenumber region of 2200 – 2500 cm^-1 that had proven some weak intermolecular interaction at the terminal N (nitrile) atoms of the dicyanamide.

Abstract: In this communication, structural, thermal and optical absorption properties of bismuth doped multicomponent tellurite glass (69TeO₂-10ZnO-10WO₃-5Na₂O-5TiO₂-1.0Bi₂O₃ (mol %)) synthesized using melt quench method is reported. The X-ray diffraction confirms the amorphous structure of the synthesized glass. IR spectrum of bismuth doped glass show band at 601 cm^-1. Raman analysis observed mainly in four spectral regions which are R1 (65-150) cm^-1, R2 (280-550) cm^-1, R3 (880-950) cm^-1 and R4 (916-926) cm^-1 and identified bands are assigned to respective molecular groups. Thermogravimetric analysis profile show stability regarding to weight loss. Differential scanning calorimetry indicates good thermal stability of the synthesized glass for its applications in optical fibers. The absorption spectrum identified the cutoff wavelength at 430 nm.