[article]
Titre : |
Free volume distribution during consolidation and coalescence of latex films |
Type de document : |
texte imprimé |
Auteurs : |
A. J. Hill, Auteur ; J. D. Cloyd, Auteur ; D. L. Murray, Auteur ; R. R. Stockl, Auteur ; P. P. Shang, Auteur ; R. L. McGill, Auteur ; M. R. Tant, Auteur |
Année de publication : |
2001 |
Article en page(s) : |
p. 115-124 |
Note générale : |
Bibliogr. |
Langues : |
Américain (ame) |
Catégories : |
Coalescence (Sciences physiques) Latex Polyméthacrylates Revêtements en phase aqueuse:Peinture en phase aqueuse
|
Tags : |
'Peinture émulsion' Latex 'Formation de film' Consolidation Coalescence 'Polyméthacrylate butyle' d'isobutyle' 'Volume libre' Annihilation positon 'Microscopie à force atomique' |
Index. décimale : |
667.9 Revêtements et enduits |
Résumé : |
The focus of the work is the effect of molecular architecture on free volume distribution during consolidation and coalescence of aqueous latex emulsions. Two series of model emulsion polymers, iso-butyl methacrylate (i-BMA) and normal-butyl methacrylate (n-BMA) dispersions with varying level of trimethylolpropanetriacrylate (TMPTA) crosslinker, are studied. Coatings are characterized by positron annihilation lifetime spectroscopy (PALS), and atomic force microscopy (AFM). Formation of coherent brittle films without significant interdiffusion is achieved by consolidation below the glass transition temperature (Tg). Consolidation, or ordering/compaction of films following water evaporation at temperatures below the MFFT, results in a decrease in the relative free volume element size, Tau 3, as measured by PALS. An increase in the characteristic relaxation time for the consolidation process is evident as TMPTA levels and corresponding gel fraction increase. Consolidation below Tg is accompanied by physical aging. Coalescence and interdiffusion are achieved by annealing films at or above Tg. Annealed coatings show a decrease in Tg and an increase in PALS free volume attributed to erasure of physical aging in combination with the action of the surfactant (sodium dodecyl sulfate) as a plasticizer. |
Permalink : |
https://e-campus.itech.fr/pmb/opac_css/index.php?lvl=notice_display&id=5693 |
in JOURNAL OF COATINGS TECHNOLOGY (JCT) > Vol. 73, N° 913 (02/2001) . - p. 115-124
[article]
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