Linked Life Data

15350922

Source:http://linkedlifedata.com/resource/pubmed/id/15350922

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
12
pubmed:dateCreated
2004-9-7
pubmed:abstractText
In this paper, FTIR spectroscopy using attenuated total reflection (ATR) and KBr pressed disk techniques has been used to characterize sorbed water and HDTMA+ in organo-clay. Sorbed water content decreases with the intercalation of HDTMA+. With the decrease of the sorbed water content, the position of the nu2 mode shifts to higher frequency dramatically while the stretching vibration shifts to lower frequency slightly, indicating that H2O is less strongly hydrogen bonded. This might be resulted from the polarization of H2O molecules by the changeable cations and HDTMA+. FTIR spectra show that both antisymmetric and symmetric CH2 stretching absorption bands shift to low frequencies with increase of amine concentration within the galleries of montmorillonite, elucidating the increase of ordered conformation. Furthermore, the present study demonstrates that the antisymmetric CH2 stretching mode is more sensitive to the conformational ordering than the symmetric stretching mode. When KBr pressed disk technique used, two well resolved absorption bands at 730 and 720 cm(-1), and at 1473 and 1463 cm(-1), corresponding to the methylene scissoring and rocking modes, respectively, could be observed in FTIR spectra of organo-clays with relative higher concentration of surfactant. However, the FTIR spectra using ATR technique only display singlets and they are independent of amine concentration and chain conformation. Our present study demonstrates that FTIR spectroscopy using KBr pressed disk technique is more suitable to probe the conformational ordering of surfactant in organo-clays than that suing ATR technique does.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Oct
pubmed:issn
1386-1425
pubmed:author
pubmed:issnType
Print
pubmed:volume
60
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
2853-9
pubmed:dateRevised
2006-11-15
pubmed:meshHeading
pubmed:year
2004
pubmed:articleTitle
Infrared study of HDTMA+ intercalated montmorillonite.
pubmed:affiliation
Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Wushan, Guangzhou 510640, China.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't