Linked Life Data

12199360

Source:http://linkedlifedata.com/resource/pubmed/id/12199360

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
3-4
pubmed:dateCreated
2002-8-29
pubmed:abstractText
Poly(vinyl alcohol) (PVA) with 55% and 61% syndiotacticity, and their related dry and hydrated gels obtained by two different freeze-thawing cycles have been investigated using the solid-state 13C CP-MAS NMR technique. From a comparative analysis of the spectra, evidence was obtained that the gelation process largely disrupts the intramolecular hydrogen-bonded network of the PVA. The addition of water to the dry gels favours their swelling, destroying intra-chain hydrogen bonds between hydroxyl groups as a function of the degree of tacticity and the gelation procedure, and promotes the formation of new networks of interchain hydrogen bonds. Information on the dynamics of the polymeric domains in the kilohertz range has been obtained from the analysis of the spin relaxation times T1rho(1H) and T1rho(13C) indicating that homogeneous arrangements of the amorphous or swollen polymeric chains exist, independent of the preparation method or the tacticity of the PVA chains.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:issn
0926-2040
pubmed:author
pubmed:issnType
Print
pubmed:volume
21
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
187-96
pubmed:dateRevised
2006-11-15
pubmed:meshHeading
pubmed:articleTitle
Solid-state 13C NMR study of poly(vinyl alcohol) gels.
pubmed:affiliation
Dipartimento di Scienze Chimiche, Universita' di Cagliari, Cittadella Universitaria di Monserrato, Italy.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't