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dc.contributor.author
Polo, Mara Lis  
dc.contributor.author
Spontón, Marisa Elisabet  
dc.contributor.author
Jaramillo, Franklin  
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Estenoz, Diana Alejandra  
dc.contributor.author
Meira, Gregorio Raul  
dc.date.available
2017-10-31T19:20:49Z  
dc.date.issued
2017-09  
dc.identifier.citation
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  
dc.identifier.issn
0021-8995  
dc.identifier.uri
http://hdl.handle.net/11336/27281  
dc.description.abstract
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.  
dc.format
application/pdf  
dc.language.iso
eng  
dc.publisher
John Wiley & Sons Inc  
dc.rights
info:eu-repo/semantics/openAccess  
dc.rights.uri
https://creativecommons.org/licenses/by-nc-sa/2.5/ar/  
dc.subject
Nmr  
dc.subject
Polyurethanes  
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Reaction Kinetics  
dc.subject
Sec  
dc.subject.classification
Otras Ingeniería Química  
dc.subject.classification
Ingeniería Química  
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INGENIERÍAS Y TECNOLOGÍAS  
dc.title
Linear segmented polyurethanes. I. A kinetics study  
dc.type
info:eu-repo/semantics/article  
dc.type
info:ar-repo/semantics/artículo  
dc.type
info:eu-repo/semantics/publishedVersion  
dc.date.updated
2017-10-30T18:45:02Z  
dc.journal.volume
135  
dc.journal.number
4  
dc.journal.pagination
1-13; 45747  
dc.journal.pais
Estados Unidos  
dc.description.fil
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  
dc.description.fil
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  
dc.description.fil
Fil: Jaramillo, Franklin. Universidad de Antioquia; Colombia  
dc.description.fil
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  
dc.description.fil
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  
dc.journal.title
Journal of Applied Polymer Science  
dc.relation.alternativeid
info:eu-repo/semantics/altIdentifier/url/http://onlinelibrary.wiley.com/doi/10.1002/app.45747/abstract  
dc.relation.alternativeid
info:eu-repo/semantics/altIdentifier/doi/http://dx.doi.org/10.1002/app.45747