Linked Life Data

20355988

Source:http://linkedlifedata.com/resource/pubmed/id/20355988

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
3
pubmed:dateCreated
2010-4-1
pubmed:abstractText
Oxygen diffusion coefficients, D, have been measured in poly(methyl methacrylate) (PMMA) films containing small amounts of a cinnamic acid derived cross-linker. In the technique employed, the time evolution of oxygen sorption into the film was monitored using the phosphorescence of singlet oxygen as a spectroscopic probe. Although the effect of adding up to 1 mol % of the cross-linker is clearly manifested in the molecular weight and T(g) of these samples, values of D are only moderately influenced. Nevertheless, a systematic decrease in the value of D is discernible as the extent of cross-linking is increased. Although it is reasonable to expect that, in a glassy polymer, cross-linking should not significantly perturb the local motions and confined changes in free volume that influence the translational motion of a small penetrant such as oxygen, our data indicate that even small amounts of a cross-linker can, nevertheless, have a noticeable and potentially meaningful effect. Although UV irradiation of the polymer films disrupts the cinnamic acid derived cross-linker via a [2 + 2] cycloreversion reaction, the photoinduced changes observed in D appear, rather, to reflect degradation reactions in the PMMA-based polymer.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Mar
pubmed:issn
1944-8244
pubmed:author
pubmed:issnType
Print
pubmed:volume
1
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
661-7
pubmed:meshHeading
pubmed:year
2009
pubmed:articleTitle
Effect of polymer cross-links on oxygen diffusion in glassy PMMA films.
pubmed:affiliation
Center for Oxygen Microscopy and Imaging and Centre for DNA Nanotechnology, Department of Chemistry, University of Aarhus, Langelandsgade 140, Arhus, Denmark.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't