Linear segmented polyurethanes. I. A kinetics study
- Autores
- Polo, Mara Lis; Spontón, Marisa Elisabet; Jaramillo, Franklin; Estenoz, Diana Alejandra; Meira, Gregorio Raul
- Año de publicación
- 2017
- Idioma
- inglés
- Tipo de recurso
- artículo
- Estado
- versión publicada
- Descripción
- This work investigates the two-step polymerization between methylene diphenyl diisocyanate (MDI), two different poly(tetramethylene oxide) macrodiols, and 1,4-butanediol (BD) as chain extender. At the end of the prepolymerization, the reaction mixture contains MDI in excess and a prepolymer with isocyanate end group. Then, BD and a solvent (tetrahydrofuran) were added to start the finishing stage under nominal stoichiometric equilibrium. The reaction was analyzed by Fourier transform infrared spectroscopy, hydrogen nuclear magnetic resonance (1H-NMR), and size exclusion chromatography. 1H-NMR was employed to follow global concentrations of unreacted isocyanate end groups and internal urethane groups. This information enabled to estimate the following ?effective? rate constants: k1 = 1.07 × 10−3 L mol−1 s−1 for the prepolymerization; and k2 = 1.94 × 10−4 L mol−1 s−1 for the finishing stage. These values are subject to errors caused by biases introduced in the recipe, in the measurements, in the reaction conditions, in the quality of reagents, and in the reaction mechanism assumptions. Such errors also explain the dispersion of the published rate constants values. The 1H-NMR measurements also enabled to estimate the evolution (with extent of reaction) of the number-average number of structural units along the prepolymerization and finishing stages; and such estimates reasonably verify Flory´s classical expressions.
Fil: Polo, Mara Lis. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Desarrollo Tecnológico para la Industria Química. Universidad Nacional del Litoral. Instituto de Desarrollo Tecnológico para la Industria Química; Argentina
Fil: Spontón, Marisa Elisabet. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Desarrollo Tecnológico para la Industria Química. Universidad Nacional del Litoral. Instituto de Desarrollo Tecnológico para la Industria Química; Argentina
Fil: Jaramillo, Franklin. Universidad de Antioquia; Colombia
Fil: Estenoz, Diana Alejandra. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Desarrollo Tecnológico para la Industria Química. Universidad Nacional del Litoral. Instituto de Desarrollo Tecnológico para la Industria Química; Argentina
Fil: Meira, Gregorio Raul. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Desarrollo Tecnológico para la Industria Química. Universidad Nacional del Litoral. Instituto de Desarrollo Tecnológico para la Industria Química; Argentina - Materia
-
Nmr
Polyurethanes
Reaction Kinetics
Sec - Nivel de accesibilidad
- acceso abierto
- Condiciones de uso
- https://creativecommons.org/licenses/by-nc-sa/2.5/ar/
- Repositorio
- Institución
- Consejo Nacional de Investigaciones Científicas y Técnicas
- OAI Identificador
- oai:ri.conicet.gov.ar:11336/27281
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Linear segmented polyurethanes. I. A kinetics studyPolo, Mara LisSpontón, Marisa ElisabetJaramillo, FranklinEstenoz, Diana AlejandraMeira, Gregorio RaulNmrPolyurethanesReaction KineticsSechttps://purl.org/becyt/ford/2.4https://purl.org/becyt/ford/2This work investigates the two-step polymerization between methylene diphenyl diisocyanate (MDI), two different poly(tetramethylene oxide) macrodiols, and 1,4-butanediol (BD) as chain extender. At the end of the prepolymerization, the reaction mixture contains MDI in excess and a prepolymer with isocyanate end group. Then, BD and a solvent (tetrahydrofuran) were added to start the finishing stage under nominal stoichiometric equilibrium. The reaction was analyzed by Fourier transform infrared spectroscopy, hydrogen nuclear magnetic resonance (1H-NMR), and size exclusion chromatography. 1H-NMR was employed to follow global concentrations of unreacted isocyanate end groups and internal urethane groups. This information enabled to estimate the following ?effective? rate constants: k1 = 1.07 × 10−3 L mol−1 s−1 for the prepolymerization; and k2 = 1.94 × 10−4 L mol−1 s−1 for the finishing stage. These values are subject to errors caused by biases introduced in the recipe, in the measurements, in the reaction conditions, in the quality of reagents, and in the reaction mechanism assumptions. Such errors also explain the dispersion of the published rate constants values. The 1H-NMR measurements also enabled to estimate the evolution (with extent of reaction) of the number-average number of structural units along the prepolymerization and finishing stages; and such estimates reasonably verify Flory´s classical expressions.Fil: Polo, Mara Lis. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Desarrollo Tecnológico para la Industria Química. Universidad Nacional del Litoral. Instituto de Desarrollo Tecnológico para la Industria Química; ArgentinaFil: Spontón, Marisa Elisabet. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Desarrollo Tecnológico para la Industria Química. Universidad Nacional del Litoral. Instituto de Desarrollo Tecnológico para la Industria Química; ArgentinaFil: Jaramillo, Franklin. Universidad de Antioquia; ColombiaFil: Estenoz, Diana Alejandra. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Desarrollo Tecnológico para la Industria Química. Universidad Nacional del Litoral. Instituto de Desarrollo Tecnológico para la Industria Química; ArgentinaFil: Meira, Gregorio Raul. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Desarrollo Tecnológico para la Industria Química. Universidad Nacional del Litoral. Instituto de Desarrollo Tecnológico para la Industria Química; ArgentinaJohn Wiley & Sons Inc2017-09info:eu-repo/semantics/articleinfo:eu-repo/semantics/publishedVersionhttp://purl.org/coar/resource_type/c_6501info:ar-repo/semantics/articuloapplication/pdfapplication/pdfhttp://hdl.handle.net/11336/27281Polo, Mara Lis; Spontón, Marisa Elisabet; Jaramillo, Franklin; Estenoz, Diana Alejandra; Meira, Gregorio Raul; Linear segmented polyurethanes. I. A kinetics study; John Wiley & Sons Inc; Journal of Applied Polymer Science; 135; 4; 9-2017; 1-13; 457470021-8995CONICET DigitalCONICETenginfo:eu-repo/semantics/altIdentifier/url/http://onlinelibrary.wiley.com/doi/10.1002/app.45747/abstractinfo:eu-repo/semantics/altIdentifier/doi/10.1002/app.45747info:eu-repo/semantics/openAccesshttps://creativecommons.org/licenses/by-nc-sa/2.5/ar/reponame:CONICET Digital (CONICET)instname:Consejo Nacional de Investigaciones Científicas y Técnicas2025-09-29T09:57:25Zoai:ri.conicet.gov.ar:11336/27281instacron:CONICETInstitucionalhttp://ri.conicet.gov.ar/Organismo científico-tecnológicoNo correspondehttp://ri.conicet.gov.ar/oai/requestdasensio@conicet.gov.ar; lcarlino@conicet.gov.arArgentinaNo correspondeNo correspondeNo correspondeopendoar:34982025-09-29 09:57:26.008CONICET Digital (CONICET) - Consejo Nacional de Investigaciones Científicas y Técnicasfalse |
dc.title.none.fl_str_mv |
Linear segmented polyurethanes. I. A kinetics study |
title |
Linear segmented polyurethanes. I. A kinetics study |
spellingShingle |
Linear segmented polyurethanes. I. A kinetics study Polo, Mara Lis Nmr Polyurethanes Reaction Kinetics Sec |
title_short |
Linear segmented polyurethanes. I. A kinetics study |
title_full |
Linear segmented polyurethanes. I. A kinetics study |
title_fullStr |
Linear segmented polyurethanes. I. A kinetics study |
title_full_unstemmed |
Linear segmented polyurethanes. I. A kinetics study |
title_sort |
Linear segmented polyurethanes. I. A kinetics study |
dc.creator.none.fl_str_mv |
Polo, Mara Lis Spontón, Marisa Elisabet Jaramillo, Franklin Estenoz, Diana Alejandra Meira, Gregorio Raul |
author |
Polo, Mara Lis |
author_facet |
Polo, Mara Lis Spontón, Marisa Elisabet Jaramillo, Franklin Estenoz, Diana Alejandra Meira, Gregorio Raul |
author_role |
author |
author2 |
Spontón, Marisa Elisabet Jaramillo, Franklin Estenoz, Diana Alejandra Meira, Gregorio Raul |
author2_role |
author author author author |
dc.subject.none.fl_str_mv |
Nmr Polyurethanes Reaction Kinetics Sec |
topic |
Nmr Polyurethanes Reaction Kinetics Sec |
purl_subject.fl_str_mv |
https://purl.org/becyt/ford/2.4 https://purl.org/becyt/ford/2 |
dc.description.none.fl_txt_mv |
This work investigates the two-step polymerization between methylene diphenyl diisocyanate (MDI), two different poly(tetramethylene oxide) macrodiols, and 1,4-butanediol (BD) as chain extender. At the end of the prepolymerization, the reaction mixture contains MDI in excess and a prepolymer with isocyanate end group. Then, BD and a solvent (tetrahydrofuran) were added to start the finishing stage under nominal stoichiometric equilibrium. The reaction was analyzed by Fourier transform infrared spectroscopy, hydrogen nuclear magnetic resonance (1H-NMR), and size exclusion chromatography. 1H-NMR was employed to follow global concentrations of unreacted isocyanate end groups and internal urethane groups. This information enabled to estimate the following ?effective? rate constants: k1 = 1.07 × 10−3 L mol−1 s−1 for the prepolymerization; and k2 = 1.94 × 10−4 L mol−1 s−1 for the finishing stage. These values are subject to errors caused by biases introduced in the recipe, in the measurements, in the reaction conditions, in the quality of reagents, and in the reaction mechanism assumptions. Such errors also explain the dispersion of the published rate constants values. The 1H-NMR measurements also enabled to estimate the evolution (with extent of reaction) of the number-average number of structural units along the prepolymerization and finishing stages; and such estimates reasonably verify Flory´s classical expressions. Fil: Polo, Mara Lis. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Desarrollo Tecnológico para la Industria Química. Universidad Nacional del Litoral. Instituto de Desarrollo Tecnológico para la Industria Química; Argentina Fil: Spontón, Marisa Elisabet. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Desarrollo Tecnológico para la Industria Química. Universidad Nacional del Litoral. Instituto de Desarrollo Tecnológico para la Industria Química; Argentina Fil: Jaramillo, Franklin. Universidad de Antioquia; Colombia Fil: Estenoz, Diana Alejandra. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Desarrollo Tecnológico para la Industria Química. Universidad Nacional del Litoral. Instituto de Desarrollo Tecnológico para la Industria Química; Argentina Fil: Meira, Gregorio Raul. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Desarrollo Tecnológico para la Industria Química. Universidad Nacional del Litoral. Instituto de Desarrollo Tecnológico para la Industria Química; Argentina |
description |
This work investigates the two-step polymerization between methylene diphenyl diisocyanate (MDI), two different poly(tetramethylene oxide) macrodiols, and 1,4-butanediol (BD) as chain extender. At the end of the prepolymerization, the reaction mixture contains MDI in excess and a prepolymer with isocyanate end group. Then, BD and a solvent (tetrahydrofuran) were added to start the finishing stage under nominal stoichiometric equilibrium. The reaction was analyzed by Fourier transform infrared spectroscopy, hydrogen nuclear magnetic resonance (1H-NMR), and size exclusion chromatography. 1H-NMR was employed to follow global concentrations of unreacted isocyanate end groups and internal urethane groups. This information enabled to estimate the following ?effective? rate constants: k1 = 1.07 × 10−3 L mol−1 s−1 for the prepolymerization; and k2 = 1.94 × 10−4 L mol−1 s−1 for the finishing stage. These values are subject to errors caused by biases introduced in the recipe, in the measurements, in the reaction conditions, in the quality of reagents, and in the reaction mechanism assumptions. Such errors also explain the dispersion of the published rate constants values. The 1H-NMR measurements also enabled to estimate the evolution (with extent of reaction) of the number-average number of structural units along the prepolymerization and finishing stages; and such estimates reasonably verify Flory´s classical expressions. |
publishDate |
2017 |
dc.date.none.fl_str_mv |
2017-09 |
dc.type.none.fl_str_mv |
info:eu-repo/semantics/article info:eu-repo/semantics/publishedVersion http://purl.org/coar/resource_type/c_6501 info:ar-repo/semantics/articulo |
format |
article |
status_str |
publishedVersion |
dc.identifier.none.fl_str_mv |
http://hdl.handle.net/11336/27281 Polo, Mara Lis; Spontón, Marisa Elisabet; Jaramillo, Franklin; Estenoz, Diana Alejandra; Meira, Gregorio Raul; Linear segmented polyurethanes. I. A kinetics study; John Wiley & Sons Inc; Journal of Applied Polymer Science; 135; 4; 9-2017; 1-13; 45747 0021-8995 CONICET Digital CONICET |
url |
http://hdl.handle.net/11336/27281 |
identifier_str_mv |
Polo, Mara Lis; Spontón, Marisa Elisabet; Jaramillo, Franklin; Estenoz, Diana Alejandra; Meira, Gregorio Raul; Linear segmented polyurethanes. I. A kinetics study; John Wiley & Sons Inc; Journal of Applied Polymer Science; 135; 4; 9-2017; 1-13; 45747 0021-8995 CONICET Digital CONICET |
dc.language.none.fl_str_mv |
eng |
language |
eng |
dc.relation.none.fl_str_mv |
info:eu-repo/semantics/altIdentifier/url/http://onlinelibrary.wiley.com/doi/10.1002/app.45747/abstract info:eu-repo/semantics/altIdentifier/doi/10.1002/app.45747 |
dc.rights.none.fl_str_mv |
info:eu-repo/semantics/openAccess https://creativecommons.org/licenses/by-nc-sa/2.5/ar/ |
eu_rights_str_mv |
openAccess |
rights_invalid_str_mv |
https://creativecommons.org/licenses/by-nc-sa/2.5/ar/ |
dc.format.none.fl_str_mv |
application/pdf application/pdf |
dc.publisher.none.fl_str_mv |
John Wiley & Sons Inc |
publisher.none.fl_str_mv |
John Wiley & Sons Inc |
dc.source.none.fl_str_mv |
reponame:CONICET Digital (CONICET) instname:Consejo Nacional de Investigaciones Científicas y Técnicas |
reponame_str |
CONICET Digital (CONICET) |
collection |
CONICET Digital (CONICET) |
instname_str |
Consejo Nacional de Investigaciones Científicas y Técnicas |
repository.name.fl_str_mv |
CONICET Digital (CONICET) - Consejo Nacional de Investigaciones Científicas y Técnicas |
repository.mail.fl_str_mv |
dasensio@conicet.gov.ar; lcarlino@conicet.gov.ar |
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score |
13.070432 |