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Investigation of water diffusion in low-density polyethylene by attenuated total reflectance fourier transform infrared spectroscopy and two-dimensional correlation analysis / Mengyin Wang in Industrial & engineering chemistry research, Vol. 50 N° 10 (Mai 2011) 

Public ISBD [article]  in Industrial & engineering chemistry research > Vol. 50 N° 10 (Mai 2011) . - pp. 6447-6454 Titre : Investigation of water diffusion in low-density polyethylene by attenuated total reflectance fourier transform infrared spectroscopy and two-dimensional correlation analysis Type de document : texte imprimé Auteurs : Mengyin Wang, Auteur ; Peiyi Wu, Auteur ; Saurav S. Sengupta, Auteur Année de publication : 2011 Article en page(s) : pp. 6447-6454 Note générale : Chimie industrielle Langues : Anglais (eng) Mots-clés : Correlation  analysis  Fourier-transformed  infrared  spectrometry  Reflectance  Density  Diffusion Résumé : Water diffusion through low density polyethylene (LDPE) film was investigated by attenuated total reflectance Fourier transform infrared (ATR-FTIR) spectroscopy and two-dimensional correlation spectroscopy (2DCOS) over a temperature range of 25-80 °C. The 2DCOS spectra of water diffusion in LDPE at different temperatures were very similar. The broad OH stretching vibration (v(OH)) was split into four bands assigned to three different types of water molecules, namely, bulk water, cluster water, and free water, which will be defined. It appeared that as water molecules disperse in LDPE, cluster water with moderate hydrogen bonds diffused faster than bulk water with strong hydrogen bonds. Additionally, the hydrogen bonds between water molecules may have been further weakened or even broken to form free water, possibly due to limited free volume. On the basis of a Fickian model, the diffusion coefficients could be calculated from overall, fast and slow diffusion process, respectively. The diffusion coefficients were observed to increase with temperature, possibly due to increased swelling of molecular chain, more free volume, and reduced size of the penetrants. DEWEY : 660 ISSN : 0888-5885 En ligne : http://cat.inist.fr/?aModele=afficheN&cpsidt=24158942 [article] Investigation of water diffusion in low-density polyethylene by attenuated total reflectance fourier transform infrared spectroscopy and two-dimensional correlation analysis [texte imprimé] / Mengyin Wang, Auteur ; Peiyi Wu, Auteur ; Saurav S. Sengupta, Auteur . - 2011 . - pp. 6447-6454. Chimie industrielle Langues : Anglais (eng) in Industrial & engineering chemistry research > Vol. 50 N° 10 (Mai 2011) . - pp. 6447-6454 Mots-clés : Correlation  analysis  Fourier-transformed  infrared  spectrometry  Reflectance  Density  Diffusion Résumé : Water diffusion through low density polyethylene (LDPE) film was investigated by attenuated total reflectance Fourier transform infrared (ATR-FTIR) spectroscopy and two-dimensional correlation spectroscopy (2DCOS) over a temperature range of 25-80 °C. The 2DCOS spectra of water diffusion in LDPE at different temperatures were very similar. The broad OH stretching vibration (v(OH)) was split into four bands assigned to three different types of water molecules, namely, bulk water, cluster water, and free water, which will be defined. It appeared that as water molecules disperse in LDPE, cluster water with moderate hydrogen bonds diffused faster than bulk water with strong hydrogen bonds. Additionally, the hydrogen bonds between water molecules may have been further weakened or even broken to form free water, possibly due to limited free volume. On the basis of a Fickian model, the diffusion coefficients could be calculated from overall, fast and slow diffusion process, respectively. The diffusion coefficients were observed to increase with temperature, possibly due to increased swelling of molecular chain, more free volume, and reduced size of the penetrants. DEWEY : 660 ISSN : 0888-5885 En ligne : http://cat.inist.fr/?aModele=afficheN&cpsidt=24158942