Fourier transform infrared spectroscopy polyethylenes

Air drying was used only for the sample treated with primer alone and was omitted for the three samples containing primer and acrylonitrile since acrylonitrile has a higher vapor pressure then methanol.(14) As a result, the electron treatment was performed on wet samples. The fifth LDPE sample was used as a virgin polyethylene control. After Irradiation, all samples were washed with luke warm water to remove any residual monomer. Because of the highly toxic nature of acrylonitrile, these coating procedures were conducted under carefully controlled conditions. All five samples (l.e. primed, 1 1, 2 1, 3 1 and control) were examined by Fourier Transform Infrared Spectroscopy (FTIR). 

Fourier Transform Infrared Spectroscopy (FTIR) provided a convenient tool by which reaction success was qualitatively evaluated. The spectrum of unfunctionalized PVBC on the polyethylene support is included in Figure 6a. Because of the intense absorbances of the PA, MPE, and IPE species, FTIR proved to be a convenient tool to investigate the progression of the syntheses. Note the changes in the spectra as the membranes were functionalized especially in the range of 900-1250 wavenumber for the MPE and IPE functional groups The PA functionalized membranes have several other very broad characteristic absorbances Figures 6b, 6c, and 6d contain the FTIR spectra of the membranes functionalized with the phosphorous species. Note that the intense absorbances around 3000 wavenumber are derived from the polyethylene support. 

DMA = dynamic mechanical analysis, DMTA = dynamic mechanical thermal analysis, DSC = differential scanning calorimetry, FTIR = Fourier transform infrared spectroscopy, GPC - gel permeation chromatography, LLDPE = linear low-density polyethylene, PMMA = polymethyl methacrylate, TGA = thermo-... 

In the Master s dissertation entitled Effect of natural and accelerated ageing on the properties of PET/PC (80/20) blend , recycled polyethylene terephthalate (rPET) was blended with PC (80/20 wt/wt), and then submitted to natural ageing in the city of Rio de Janeiro [17]. For comparison purposes, we also monitored the accelerated ageing of the blend in an appropriate chamber under the same conditions, 2,000 h of exposure were performed. The Fourier-Transform infrared spectroscopy revealed the tendency of the PET and PC carbonyl indices to decrease upon an increase in... 

Prasad, A. (1998) A quantitative analysis of low density polyethylene and linear low density polyethylene blends by differential scanning calorimetry and Fourier transform infrared spectroscopy methods. J. Polym. Eng. Sci., 38, 1716-1728. 

Ethylene-styrene copolymer Ethylene-vinyl acetate copolymer Ethylene-vinylchloride copolymer Fourier transform infrared spectroscopy Gas chromatography High-density polyethylene Hydroperoxide decomposition Isobutylene... 

Scanning electrochemical microscopy (SECM) has been applied to polymethylmethacrylate, polystyrene and polyethylene glycol. Surface enhanced infrared reflection microscopy was applied to polyacrylonitrile, polybutadiene and styrene resins whilst Fourier transform infrared spectroscopy was applied to polyimides. Finally, nuclear magnetic resonance spectroscopy has been applied to the examination of the surfaces of films of polyethylene, Suryln and ethylene-vinyl acetate copolymer. ... 

UHMWPE were specifically identified (e.g., polyethylene terephthalate [PET], polyethylene [PE], polyamide, polyvinyl alcohol [PVOH]) by declaration of the manufacturer and by using Fourier transform infrared spectroscopy (FTIR) (System 2000, Perkin-EImer, Shelton, Connecticut, USA). The packaging materials were identified as one of seven types, as summarized in Table 3.3. 

Differential scanning calorimetry and Fourier transform infrared spectroscopy techniques were used to study the structure of water molecules in polyvinyl alcohol and polyethylene grafted acrylate hydrophilic polymers. Varying amounts of water were added to test samples and the samples conditioned to the sorption equilibrium state in sealed containers for 24 hours prior to evaluation. It was concluded that below a threshold water content, depending on the polymers physical and chemical stmcture, water molecules absorbed in hydrophilic polymer cannot form ice crystals in the polymer matrix. Above this threshold content, the water crystallises but below zero. It was also demonstrated that the absorbed water in hydrophilic polymers develops differing hydrogen bonds in the first and second hydration layers. It was concluded that the potential influence of these intermolecular interactions should therefore be taken into account whenever a polymer is used with a solvent. 25 refs. 

Virgin and recycled polyethylene terephthalate (PET) was blended with polyether-imide (PEI) in proportions between 0 and 50 percent PEI content and samples were examined by differential scaiming calorimetry and Fourier transform infrared spectroscopy. All blends were completely miscible, as indicated by a single glass transition temperature which is dependent on blend composition. Crystallisation rates of PET were retarded strongly at 20 percent PEI content and above, but degree of crystallinity was easily determined from a linear correlation between a structural parameter measured spectroscopically and enthalpy of fusion. Trans conformer activation energy measurement confirmed the effects of PEI content on crystallisation of PET. 9 refs. 

Fourier Transform Infrared Spectroscopy Analysis A ThermoNicolet Nexus 470 spectrometer was used for FTIR analysis to detect the presence of functional groups in the membranes. Thin membrane samples were attached to a polyethylene substrate FTIR card from Thermo Electron Cotp. and analyzed at ambient temperature. All spectra were obtained from 100 scans at 4.0 cm resolution with spectra ranging from 400 to 4000 cm. ... 

Infrared (IR) spectroscopy [invariably Fourier transform infrared spectroscopy (FTIR)] is used to determine a variety of molecular characteristics of polyethylene. It may be used to identify and quantify various additives and chemical groups attached to the polyethylene backbone. Additionally it can provide information with respect to solid-state morphology, which is addressed in Section IV. 

Long-term oxidative degradation of an ion-beam irradiated polymer was studied. Silicon oxide thin layers were deposited on the surfaces of high density polyethylene (HDPE) to suppress the oxygen permeation. HDPE samples irradiated with a C6+ ion-beam were stored up to 12 months after the irradiation and the evolution of the chemical structure was followed by micro-Fourier transform infrared (micro-FT-IR) spectroscopy. Silicon oxide layers were found effective to suppress the long-term oxidative degradation of the ion-irradiated polymer. 

ECD = electron capture detector EPA = Environmental Protection Agency FEWS = fiber evanescent wave spectroscopy FID = flame ionization detection FT-IR = Fourier transform infrared GC = gas chromatography HECD = Hall electrolytic conductivity detector HRGC = high resolution gas chromatography HSD = halide-sensitive detector H2SO4 = sulfuric acid LDPE = low-density polyethylene MS = mass spectrometry NIOSH = National Institute for Occupational Safety and Health NR = not reported PI = photoionization UV = ultraviolet detection... 

This chapter treats principally the vibrational spectra determined by infrared and Raman spectroscopy. The means used to assign infrared absorption bands are outlined. Also, the rationale for the selection of permitted absorption bands is described. The basis for the powerful technique of Fourier Transform Infrared (FTIR) is presented in Appendix 6A. Polyethylene is used to illustrate both band assignment and the application of selection rules because its simple chain structure and its commercial importance have made polyethylene the most thoroughly studied polymer. The techniques of nuclear magnetic resonance, neutron inelastic scattering and ultraviolet spectroscopy are briefly described. The areas of dielectric loss and dynamic mechanical loss are not presented in this chapter, but material on these techniques can be found in Chapters 5. 

Ethylene-vinyl acetate copolymer, terpene-phenol resins, polyethylene oxide, PMMA and some of their blends were solution cast on basic (aluminium oxide) and acidic (hydroxylated glass) substrates. Fourier transform infrared reflection absorption spectroscopy (IRRAS) was used to determine both the nature and the free energy of interfacial adduct formation in the polymer/metal systems. A correlation between IRRAS and adhesive strength may be used to predict both the acid-base work of adhesion and the density of interfacial interacting sites. 14 refs. 

Commereuc and co-workers [44] examined the products resulting from the photo and thermal decomposition under vacuum of a pre-oxidised isotactic polypropylenes containing a known content of hydroperoxide. In contrast to the case of polyethylene (PE), few products were retained in the polymer matrix. Detailed analysis of the gas phase was performed by GC, Fourier-transform infrared (FT-IR) spectroscopy and MS. About 70% of the hydroperoxides were converted into gaseous products such as acetone, acetic acid and methanol. Mechanisms for their formation were suggested, and the consequences of such a phenomenon for the evaluation of ageing in polypropylene (PP) were discussed. 

Spanget-Larsen, J. 1992. Fourier transform infrared hnear-dichroism spectroscopy of 1,8-di-hydroxy-9,10-anthraquinone aligned in stretched polyethylene. SPIE Proc. 1575 404-406. 

Radziszewski, J.G., and J. Michl. Fourier-transform infrared linear dichroism. Stretched polyethylene as a solvent in IR spectroscopy. J. Am. Chem. Soc. 108 3289-3297. 

Ulmschneider, M., and Pdnigault, E. (2000b), Direct identification of key-intermediates in containers using Fourier-Transform near-infrared spectroscopy through the protective polyethylene primary packaging, Analusis, 28,136-140. 

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