Wide angle X-ray spectroscopy WAXS

Spectroscopy, 490. See also 13C NMR spectroscopy FT Raman spectroscopy Fourier transform infrared (FTIR) spectrometry H NMR spectroscopy Infrared (IR) spectroscopy Nuclear magnetic resonance (NMR) spectroscopy Positron annihilation lifetime spectroscopy (PALS) Positron annihilation spectroscopy (PAS) Raman spectroscopy Small-angle x-ray spectroscopy (SAXS) Ultraviolet spectroscopy Wide-angle x-ray spectroscopy (WAXS)... 

Water-soluble poly(p-phenylene), 493 Water reducible materials, 237 WAXS. See Wide-angle x-ray spectroscopy (WAXS)... 

The evidence from wide angle x-ray scattering (WAXS), differential scanning calorimetry (DSC), and IR spectroscopy (IR) shows that both polymers crystallize separately according to their own unit cell structure. The WAXS diffraction lines of each component are present in the blends no new bands appear (12,13,14). By DSC one observes the melting peaks corresponding to each polymer (Figure 1), and IR shows the typical characteristic crystalline bands of the pure polymers in the blends. The IR spectra of the blend can essentially be accounted for as the sum of the spectra of the components. 

PVC has a complex particle morphology and a low degree of crystallinity. The crystallinity of PVC increases with increase in syndiotacticity. The level of syndiotacticity rises with fall in the temperature of polymerisation, and in the case of commercial types of PVC-S reaches 54-56%, whereas their crystallinity is only about 10%. The presence of crystalline forms in PVC has been established by studies using e.g. small-angle x-ray scattering, wide-angle X-ray diffraction (WAXS), IR spectroscopy and differential scanning calorimetry (DSC). In PVC, crystallites are formed under conversion conditions of less than 2%. These... 

Figure 2 shows how glass transition temperatures (Tg) obtained by dynamic mechanical spectroscopy (DMS), percent crystallinities obtained by wide angle x-ray scattering (WAXS) or differential scanning calorimetry (DSC), experimental diffusion coefficients, and information on tortuosity obtained by studies of morphology, can be useful in applying both the theory of V D and the model of P D. The Williams-Landel-Ferry (WLF) parameters [18] c % and C2 , which can be determined by DMS, are needed as additional input for the theory of V D. Densities and thermal expansion coefficients are needed as additional input for the model of P D. 

VTMS Vinyl trimethoxysilane WAXD Wide-angle X-ray diffraction WAXS Wide-angle X-ray scattering XPS X-ray photoelectron spectroscopy ZnSt Zinc stearate... 

Fig. 48 Assembly of a lamellar-forming polypeptide-coil diblock copolymer depicting the main techniques employed in our studies. Small-angle X-ray scattering (SAXS) is employed for the domain spacing, d. C NMR and wide-angle X-ray scattering (WAXS) are employed to identify the type of the peptide secondary structure (a-helical in the schematic). WAXS is further employed to specify the lateral self-assembly of a-helices within the polypeptide domain (a hexagonal lattice is indicated). Dielectric spectroscopy (DS) and site-specific NMR techniques are employed for the dynamics. Furthermore, the most intense DS process provides the persistence length. Ip, of a-helical segments [181]...

One recent work illustrates a good example of an orientational polymer study [21]. The molecular mechanisms involved in the residual stress in relation to shape memory effects in glassy amorphous starch has been investigated using a combination of synchrotron-based Wide Angle X-ray Scattering (WAXS) and polarized SR infrared micro-spectroscopy. The aim of this study was to analyse and better understand the structural anisotropy... 

The commonest techniques for measuring crystallinity are density, wide-angle X-ray scattering (WAXS), Fourier transform infrared spectroscopy (FTIR) and differential scanning calorimetry (DSC). 

Penn and Milanovich [31] expressed surprise that they did not find any frequency shifts during the deformation of aramid fibres, luring in mind the earlier polymer deformation studies using infrared [42] and Raman spectroscopy [8] and wide-angle X-ray scattering (WAXS) studies of deformed aramid fibres [39]. The situation was confused further by the publication by Edwards and Hadiki [34], who reported that no Raman band shifts were found when Kevlar... 

These novel films were characterized by Raman [127] and NMR [132] spectroscopies, wide-angle X-ray scattering (WAXS), and SAXS [127,128,133]. Tests of swelling in various solvents and in water and results of conductivity (by impedance spectroscopy) indicated that these films were potential proton exchange membranes for fuel cell applications [129,134]. Indeed, the higher the content of sulfonic acid functions, the higher the conductivity, and these values are enhanced when the crystallinity rate decreases [128]. 

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