Liquid biphase systems formed in ternary mixtures of two organic solvents and ethylene oxide oligomers or polymers
Autor(a) principal: | |
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Data de Publicação: | 2000 |
Outros Autores: | , |
Tipo de documento: | Artigo |
Idioma: | eng |
Título da fonte: | Journal of the Brazilian Chemical Society (Online) |
Texto Completo: | http://old.scielo.br/scielo.php?script=sci_arttext&pid=S0103-50532000000400009 |
Resumo: | Phase equilibrium data were determined for ternary systems containing ethylene oxide oligomers or polymers, heptane and one of three organic solvents (methanol, dichloromethane or chloroform). The effects of temperature, of polymer molecular weight and of the chemical nature of the organic solvent on phase equilibrium were investigated. For all the studied systems, the miscibility region was reduced as temperature decreased, indicating an exothermic phase separation process. For both binary and ternary mixtures, the miscibility also decreased as the macromolecule size increased, although this effect was less significant for the ternary mixtures. These features suggest that phase separation is more influenced by enthalpic than entropic contributions. Regarding the different polar solvents investigated, methanol presented a much smaller miscibility region, in accordance with its inferior solvation ability for PEO. The largest miscibility region was observed with chloroform, not much different from the behaviour observed with dichloromethane. Tie lines were determined for some systems, confirming the strong segregation between polymer and the hydrocarbon solvent. |
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Journal of the Brazilian Chemical Society (Online) |
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Liquid biphase systems formed in ternary mixtures of two organic solvents and ethylene oxide oligomers or polymerspoly(ethylene oxide)liquid-liquid equilibriapolymer solutionspreferential solvationPhase equilibrium data were determined for ternary systems containing ethylene oxide oligomers or polymers, heptane and one of three organic solvents (methanol, dichloromethane or chloroform). The effects of temperature, of polymer molecular weight and of the chemical nature of the organic solvent on phase equilibrium were investigated. For all the studied systems, the miscibility region was reduced as temperature decreased, indicating an exothermic phase separation process. For both binary and ternary mixtures, the miscibility also decreased as the macromolecule size increased, although this effect was less significant for the ternary mixtures. These features suggest that phase separation is more influenced by enthalpic than entropic contributions. Regarding the different polar solvents investigated, methanol presented a much smaller miscibility region, in accordance with its inferior solvation ability for PEO. The largest miscibility region was observed with chloroform, not much different from the behaviour observed with dichloromethane. Tie lines were determined for some systems, confirming the strong segregation between polymer and the hydrocarbon solvent.Sociedade Brasileira de Química2000-08-01info:eu-repo/semantics/articleinfo:eu-repo/semantics/publishedVersiontext/htmlhttp://old.scielo.br/scielo.php?script=sci_arttext&pid=S0103-50532000000400009Journal of the Brazilian Chemical Society v.11 n.4 2000reponame:Journal of the Brazilian Chemical Society (Online)instname:Sociedade Brasileira de Química (SBQ)instacron:SBQ10.1590/S0103-50532000000400009info:eu-repo/semantics/openAccessSpitzer,MarcosSilva,Luís H.M. daLoh,Watsoneng2000-11-17T00:00:00Zoai:scielo:S0103-50532000000400009Revistahttp://jbcs.sbq.org.brONGhttps://old.scielo.br/oai/scielo-oai.php||office@jbcs.sbq.org.br1678-47900103-5053opendoar:2000-11-17T00:00Journal of the Brazilian Chemical Society (Online) - Sociedade Brasileira de Química (SBQ)false |
dc.title.none.fl_str_mv |
Liquid biphase systems formed in ternary mixtures of two organic solvents and ethylene oxide oligomers or polymers |
title |
Liquid biphase systems formed in ternary mixtures of two organic solvents and ethylene oxide oligomers or polymers |
spellingShingle |
Liquid biphase systems formed in ternary mixtures of two organic solvents and ethylene oxide oligomers or polymers Spitzer,Marcos poly(ethylene oxide) liquid-liquid equilibria polymer solutions preferential solvation |
title_short |
Liquid biphase systems formed in ternary mixtures of two organic solvents and ethylene oxide oligomers or polymers |
title_full |
Liquid biphase systems formed in ternary mixtures of two organic solvents and ethylene oxide oligomers or polymers |
title_fullStr |
Liquid biphase systems formed in ternary mixtures of two organic solvents and ethylene oxide oligomers or polymers |
title_full_unstemmed |
Liquid biphase systems formed in ternary mixtures of two organic solvents and ethylene oxide oligomers or polymers |
title_sort |
Liquid biphase systems formed in ternary mixtures of two organic solvents and ethylene oxide oligomers or polymers |
author |
Spitzer,Marcos |
author_facet |
Spitzer,Marcos Silva,Luís H.M. da Loh,Watson |
author_role |
author |
author2 |
Silva,Luís H.M. da Loh,Watson |
author2_role |
author author |
dc.contributor.author.fl_str_mv |
Spitzer,Marcos Silva,Luís H.M. da Loh,Watson |
dc.subject.por.fl_str_mv |
poly(ethylene oxide) liquid-liquid equilibria polymer solutions preferential solvation |
topic |
poly(ethylene oxide) liquid-liquid equilibria polymer solutions preferential solvation |
description |
Phase equilibrium data were determined for ternary systems containing ethylene oxide oligomers or polymers, heptane and one of three organic solvents (methanol, dichloromethane or chloroform). The effects of temperature, of polymer molecular weight and of the chemical nature of the organic solvent on phase equilibrium were investigated. For all the studied systems, the miscibility region was reduced as temperature decreased, indicating an exothermic phase separation process. For both binary and ternary mixtures, the miscibility also decreased as the macromolecule size increased, although this effect was less significant for the ternary mixtures. These features suggest that phase separation is more influenced by enthalpic than entropic contributions. Regarding the different polar solvents investigated, methanol presented a much smaller miscibility region, in accordance with its inferior solvation ability for PEO. The largest miscibility region was observed with chloroform, not much different from the behaviour observed with dichloromethane. Tie lines were determined for some systems, confirming the strong segregation between polymer and the hydrocarbon solvent. |
publishDate |
2000 |
dc.date.none.fl_str_mv |
2000-08-01 |
dc.type.driver.fl_str_mv |
info:eu-repo/semantics/article |
dc.type.status.fl_str_mv |
info:eu-repo/semantics/publishedVersion |
format |
article |
status_str |
publishedVersion |
dc.identifier.uri.fl_str_mv |
http://old.scielo.br/scielo.php?script=sci_arttext&pid=S0103-50532000000400009 |
url |
http://old.scielo.br/scielo.php?script=sci_arttext&pid=S0103-50532000000400009 |
dc.language.iso.fl_str_mv |
eng |
language |
eng |
dc.relation.none.fl_str_mv |
10.1590/S0103-50532000000400009 |
dc.rights.driver.fl_str_mv |
info:eu-repo/semantics/openAccess |
eu_rights_str_mv |
openAccess |
dc.format.none.fl_str_mv |
text/html |
dc.publisher.none.fl_str_mv |
Sociedade Brasileira de Química |
publisher.none.fl_str_mv |
Sociedade Brasileira de Química |
dc.source.none.fl_str_mv |
Journal of the Brazilian Chemical Society v.11 n.4 2000 reponame:Journal of the Brazilian Chemical Society (Online) instname:Sociedade Brasileira de Química (SBQ) instacron:SBQ |
instname_str |
Sociedade Brasileira de Química (SBQ) |
instacron_str |
SBQ |
institution |
SBQ |
reponame_str |
Journal of the Brazilian Chemical Society (Online) |
collection |
Journal of the Brazilian Chemical Society (Online) |
repository.name.fl_str_mv |
Journal of the Brazilian Chemical Society (Online) - Sociedade Brasileira de Química (SBQ) |
repository.mail.fl_str_mv |
||office@jbcs.sbq.org.br |
_version_ |
1750318164148748288 |