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Fourier transform infrared resonance FTIR

Most hydrocarbon resins are composed of a mixture of monomers and are rather difficult to hiUy characterize on a molecular level. The characteristics of resins are typically defined by physical properties such as softening point, color, molecular weight, melt viscosity, and solubiHty parameter. These properties predict performance characteristics and are essential in designing resins for specific appHcations. Actual characterization techniques used to define the broad molecular properties of hydrocarbon resins are Fourier transform infrared spectroscopy (ftir), nuclear magnetic resonance spectroscopy (nmr), and differential scanning calorimetry (dsc). [Pg.350]

In this chapter, three methods for measuring the frequencies of the vibrations of chemical bonds between atoms in solids are discussed. Two of them, Fourier Transform Infrared Spectroscopy, FTIR, and Raman Spectroscopy, use infrared (IR) radiation as the probe. The third, High-Resolution Electron Enetgy-Loss Spectroscopy, HREELS, uses electron impact. The fourth technique. Nuclear Magnetic Resonance, NMR, is physically unrelated to the other three, involving transitions between different spin states of the atomic nucleus instead of bond vibrational states, but is included here because it provides somewhat similar information on the local bonding arrangement around an atom. [Pg.413]

Fourier transform infrared spectroscopy (FTIR) and proton nuclear magnetic resonance spectroscopy ( ll NMR) have become standards for verifying the chemistry of polyanhydrides. The reader is referred to the synthesis literature in the previous section for spectra of specific polymers. The FTIR spectrum for PSA is shown in Fig. 2. In FTIR the absorption... [Pg.189]

NMR spectrum. Fourier transform nuclear magnetic resonance (FTNMR) instruments, which are similar in principle to Fourier transform infrared spectrometry (FTIR) instruments, are popular today. We will briefly describe these instruments later in this section. [Pg.283]

In this Sect, we describe the starting material impurities and their effect on the processing and cure reactions of TGDDM-DDS epoxies. The cure reactions are characterized by differential scanning calorimetry (DSC) and Fourier transform infrared spectroscopy (FTIR) studies. The BF3 amine catalysts used to accelerate the cure of TGDDM-DDS epoxies are characterized by nuclear magnetic resonance (NMR) spectroscopy studies. [Pg.7]

In the case of an unknown chemical, or where resonance overlap occurs, it may be necessary to call upon the full arsenal of NMR methods. To confirm a heteronuclear coupling, the normal H NMR spectrum is compared with 1H 19F and/or XH 31 P NMR spectra. After this, and, in particular, where a strong background is present, the various 2-D NMR spectra are recorded. Homonuclear chemical shift correlation experiments such as COSY and TOCSY (or some of their variants) provide information on coupled protons, even networks of protons (1), while the inverse detected heteronuclear correlation experiments such as HMQC and HMQC/TOCSY provide similar information but only for protons coupling to heteronuclei, for example, the pairs 1H-31P and - C. Although interpretation of these data provides abundant information on the molecular structure, the results obtained with other analytical or spectrometric techniques must be taken into account as well. The various methods of MS and gas chromatography/Fourier transform infrared (GC/FTIR) spectroscopy supply complementary information to fully resolve or confirm the structure. Unambiguous identification of an unknown chemical requires consistent results from all spectrometric techniques employed. [Pg.343]

Infrared spectroscopy (IR) is one of the oldest instrumental analytical techniques but its value in structural analysis has decreased with the rise of nuclear magnetic resonance (NMR) spectroscopy and mass spectrometry (MS). Compared to the traditional dispersive IR techniques, Fourier transform infrared spectroscopy (FTIR) offers more sampling techniques. [Pg.353]

The most useful spectral methods for the characterization of water in solids are Fourier transform infrared spectroscopy (FTIR), nuclear magnetic resonance (NMR), and powder X-ray diffraction (XRD). A thorough treatment of these methods is not given here instead the example of ampicillin presented by Brittan, et sdP is summarized. [Pg.2378]

TEM), electron paramagnetic resonance (EPR) and Fourier-transform infrared spectroscopy (FTIR). [Pg.366]

The samples were characterized by means of X-ray diffraction (XRD) analysis, Fourier-transform infrared spectroscopy (FTIR), transmission electron microscopy (TEM), electron diffraction (ED), and Mossbauer spectroscopy. XRD analysis was carried out on a HZG-4A diffractometer by using Ni-filtered Co Ka radiation. IR-spectra were recorded on an AVATAR FTIR-330 spectrometer. TEM/ED examinations were performed with a LEO 906E and a JEOL 4000 EX transmission electron microscopes. The resonance spectra were recorded in air at 298 K and processed by using a commercial SM2201 MSssbauer spectrometer equipped with a 15 mCi Co (Rh) source. [Pg.602]

The spectroscopic methods which have been most usefully employed to date are nuclear magnetic resonance (NMR) and infrared spectroscopy (nowadays usually Fourier transform infrared spectroscopy, FTIR). Other methods which have been less widely used are ultraviolet-visible spectroscopy, X-ray photoelectron spectroscopy (XPS) and Raman spectroscopy. Two monographs provide general... [Pg.157]

The work described in the present paper concerns the Influence of water and organic solvents on the ionic interactions in lightly sulfonated polystyrene (SFS) ionomers. The focus will be specifically directed towards the Influence of the solvent environment on the cation-anion and cation-cation interactions. Fourier transform Infrared spectroscopy (FTIR) was used to probe the former while electron spin resonance spectroscopy (ESR) was used to study the latter. Experiments were carried out with dissolved, swollen, and bulk ionomers. [Pg.37]

Framework and Surfaces Since compositions and structures are very diverse, surface and framework properties are also extremely varied. In terms of compositions, coordination, and chemical environments, several methods are particularly informative for the characterization of nanoporous solids, such as nuclear magnetic resonance methods (NMR), UV-visible spectroscopy, Fourier-transform infrared spectroscopy (FTIR), Raman spectroscopy, x-ray absorption spectroscopies, x-ray photoelectron emission spectroscopy (XPS), and electron paramagnetic resonance (EPR) (4, 6). Among them, sohd state NMR techniques arc largely employed and will be briefly described in the following. [Pg.256]

We first have confirmed the presence of polymeric materials in the SEI by Fourier transform infrared spectroscopy (FTIR), X-ray photoelectron spectroscopy (XPS), time of flight-secondary ion mass spectroscopy (TOF-SIMS), and proton nuclear magnetic resonance spectroscopy ( H-NMR), as exemplified in Figs. 4.7 and 4.8. The FTIR and XPS (01s) spectra indicated the presence of C = C bonds and polymeric materials, respectively. The TOF-SIMS revealed the existence of... [Pg.80]

Leufgen et al. [82] reported the investigation of a template-assembled synthetic protein (TASP) conformation and its orientation in self-assembled monolayers (SAM) by means of TOF-SIMS. In this study, both the presence and molecular orientation of the TASP molecule can be monitored by TOF-SIMS, and furthermore, the influence of self-assembly protocols on the TASP molecular surface orientation can be studied by TOF-SIMS, although Fourier transform infrared spectroscopy (FTIR) and surface plasmon resonance (SPR) fail in this case. [Pg.250]


See other pages where Fourier transform infrared resonance FTIR is mentioned: [Pg.1016]    [Pg.1016]    [Pg.140]    [Pg.387]    [Pg.107]    [Pg.72]    [Pg.23]    [Pg.242]    [Pg.5]    [Pg.179]    [Pg.3]    [Pg.2507]    [Pg.259]    [Pg.7]    [Pg.1674]    [Pg.22]    [Pg.365]    [Pg.276]    [Pg.62]    [Pg.364]    [Pg.386]    [Pg.259]    [Pg.6]    [Pg.106]    [Pg.362]    [Pg.369]    [Pg.1134]    [Pg.157]    [Pg.508]    [Pg.39]    [Pg.19]    [Pg.271]    [Pg.177]    [Pg.541]   
See also in sourсe #XX -- [ Pg.19 , Pg.22 , Pg.37 ]




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