Alquilação redutiva da quitosana a partir do glutaraldeído e 3-amino-1-pr
Autor(a) principal: | |
---|---|
Data de Publicação: | 2008 |
Tipo de documento: | Dissertação |
Idioma: | por |
Título da fonte: | Repositório Institucional da UFRN |
Texto Completo: | https://repositorio.ufrn.br/jspui/handle/123456789/17591 |
Resumo: | Chitosan derivatives were prepared by reductive alkylation using glutaraldehyde and 3-amino-1-propanol. The reducing agent used was the sodium borohydride. Tests of solubility, stability and viscosity were performed in order to evaluate these parameters effects in the reaction conditions (molar ratio of the reactants and presence of nitrogen in the reaction system). The molecular structure of commercial chitosan was determined by infrared (IR) and hydrogen nuclear magnetic resonance spectroscopy (1H NMR). The intrinsic viscosity and average molecular weight of the chitosan were determined by viscosimetry in 0.3 M acetic acid aqueous solution 0.2 M sodium acetate at 25 ºC. The derivatives of chitosan soluble in aqueous acidic medium were characterized by 1H NMR. The rheological behavior of the chitosan and of the derivative of chitosan (sample QV), which presented the largest viscosity, were studied as a function of polymer concentration, temperature and ionic strength of the medium. The results of characterization of the commercial chitosan (the degree of deacetylation obtained equal 78.45 %) used in this work confirmed a sample of low molar weight (Mv = 3.57 x 104 g/mol) and low viscosity (intrinsic viscosity = 213.56 mL/g). The chemical modification of the chitosan resulted in derivatives with thickening action. The spectra of 1H NMR of the soluble derivatives in acid aqueous medium suggested the presence of hydrophobic groups grafted into chitosan in function of the chemical modification. The solubility of the derivatives of chitosan in 0.25 M acetic acid aqueous solution decreased with increase of the molar ratio of the glutaraldehyde and 3-amino-1-propanol in relation to the chitosan. The presence of nitrogen and larger amount of reducing agent in reaction system contributed to the increase of the solubility, the stability and the viscosity of the systems. The viscosity of the polymeric suspensions in function of the shear rate increased significantly with polymer concentration, suggesting the formation of strong intermolecular associations. The chitosan presented pseudoplastic behavior with the increase in polymer concentration at a low shear rate. The derivative QV presented pseudoplastic behavior at all concentrations used and in a large range of shear rate. The viscosity of chitosan in solution decreased with an increase of the temperature and with the presence of salt. However, there was an increase of the viscosity of the chitosan solution at higher temperature (65 ºC) and ionic strength of the medium which were promoted by hydrophobic associating of the acetamide groups. The solutions of the chitosan derivatives (sample QV) were significantly more viscous than chitosan solution and showed higher thermal stability in the presence of salt as a function of the hydrophobic groups grafted into chitosan backbone |
id |
UFRN_3a99564bb491da57c72c5c1808c177b9 |
---|---|
oai_identifier_str |
oai:https://repositorio.ufrn.br:123456789/17591 |
network_acronym_str |
UFRN |
network_name_str |
Repositório Institucional da UFRN |
repository_id_str |
|
spelling |
Alves, Keila dos Santoshttp://lattes.cnpq.br/7711521318854102Delpech, Márcia Cerqueirahttp://lattes.cnpq.br/7492555701225765Vidal, Rosângela Regia Limahttp://lattes.cnpq.br/3249504806789438Balaban, Rosângela de Carvalho2014-12-17T15:41:41Z2009-03-102014-12-17T15:41:41Z2008-02-29ALVES, Keila dos Santos. Reductive alkylation of chitosan by glutaraldehyde and 3-amino-1-propanol. 2008. 100 f. Dissertação (Mestrado em Físico-Química; Química) - Universidade Federal do Rio Grande do Norte, Natal, 2008.https://repositorio.ufrn.br/jspui/handle/123456789/17591Chitosan derivatives were prepared by reductive alkylation using glutaraldehyde and 3-amino-1-propanol. The reducing agent used was the sodium borohydride. Tests of solubility, stability and viscosity were performed in order to evaluate these parameters effects in the reaction conditions (molar ratio of the reactants and presence of nitrogen in the reaction system). The molecular structure of commercial chitosan was determined by infrared (IR) and hydrogen nuclear magnetic resonance spectroscopy (1H NMR). The intrinsic viscosity and average molecular weight of the chitosan were determined by viscosimetry in 0.3 M acetic acid aqueous solution 0.2 M sodium acetate at 25 ºC. The derivatives of chitosan soluble in aqueous acidic medium were characterized by 1H NMR. The rheological behavior of the chitosan and of the derivative of chitosan (sample QV), which presented the largest viscosity, were studied as a function of polymer concentration, temperature and ionic strength of the medium. The results of characterization of the commercial chitosan (the degree of deacetylation obtained equal 78.45 %) used in this work confirmed a sample of low molar weight (Mv = 3.57 x 104 g/mol) and low viscosity (intrinsic viscosity = 213.56 mL/g). The chemical modification of the chitosan resulted in derivatives with thickening action. The spectra of 1H NMR of the soluble derivatives in acid aqueous medium suggested the presence of hydrophobic groups grafted into chitosan in function of the chemical modification. The solubility of the derivatives of chitosan in 0.25 M acetic acid aqueous solution decreased with increase of the molar ratio of the glutaraldehyde and 3-amino-1-propanol in relation to the chitosan. The presence of nitrogen and larger amount of reducing agent in reaction system contributed to the increase of the solubility, the stability and the viscosity of the systems. The viscosity of the polymeric suspensions in function of the shear rate increased significantly with polymer concentration, suggesting the formation of strong intermolecular associations. The chitosan presented pseudoplastic behavior with the increase in polymer concentration at a low shear rate. The derivative QV presented pseudoplastic behavior at all concentrations used and in a large range of shear rate. The viscosity of chitosan in solution decreased with an increase of the temperature and with the presence of salt. However, there was an increase of the viscosity of the chitosan solution at higher temperature (65 ºC) and ionic strength of the medium which were promoted by hydrophobic associating of the acetamide groups. The solutions of the chitosan derivatives (sample QV) were significantly more viscous than chitosan solution and showed higher thermal stability in the presence of salt as a function of the hydrophobic groups grafted into chitosan backboneDerivados de quitosana foram preparados através de alquilação redutiva usando glutaraldeído e 3-amino-1-propanol. O agente redutor utilizado foi o boro hidreto de sódio. Os efeitos das variáveis reacionais (proporções molares dos reagentes e nitrogênio no meio reacional) nas características dos polímeros em função das mudanças estruturais foram avaliados através de testes de solubilidade, estabilidade e viscosidade. A estrutura molecular da quitosana comercial foi determinada por espectroscopia de infravermelho (IV) e de ressonância magnética nuclear de hidrogênio (RMN 1H). A viscosidade intrínseca e a massa molar média da quitosana foram determinadas por viscosimetria, em ácido acético 0,3 M acetato de sódio 0,2 M, a 25 ºC. Os derivados de quitosana solúveis em meio aquoso ácido foram caracterizados por RMN 1H. O comportamento reológico da quitosana e do seu derivado (amostra QV), que apresentou maior viscosidade, foram estudados em função da concentração de polímero, da temperatura e da força iônica do meio. Os resultados da caracterização da quitosana comercial utilizada neste trabalho demonstraram uma amostra de baixa massa molar (Mv = 3,57 x 104 g/mol) e de baixa viscosidade (viscosidade intrínseca = 213,56 mL/g). O grau médio de desacetilação foi 78,45 %. A modificação química da quitosana resultou em derivados com características viscosificantes. Os espectros de RMN 1H dos derivados solúveis em meio aquoso ácido mostraram a inserção de grupos hidrofóbicos na estrutura da quitosana em função da modificação química realizada. A solubilidade dos derivados de quitosana em solução aquosa de ácido acético 0,25 M diminuiu com o aumento da proporção molar do glutaraldeído e 3-amino-1-propanol em relação à quitosana. A presença de nitrogênio e maior quantidade de agente redutor no meio reacional contribuíram para o aumento da solubilidade, estabilidade e viscosidade dos sistemas poliméricos. A viscosidade das dispersões poliméricas em função da taxa de cisalhamento aumentou significativamente com a concentração de polímero, sugerindo a formação de fortes associações intermoleculares. A quitosana apresentou comportamento pseudoplástico com o aumento da concentração de polímero em solução e a baixas taxas de cisalhamento, enquanto que o seu derivado, QV, apresentou comportamento pseudoplástico em todas as concentrações utilizadas e em uma larga faixa de taxa de cisalhamento. A viscosidade da solução de quitosana diminuiu com o aumento da temperatura e com a presença de sal. No entanto, houve um aumento da viscosidade da solução de quitosana à temperatura mais alta (65 ºC) e em maior força iônica, promovido por associações hidrofóbicas dos grupos acetamido. As soluções do derivado QV foram significativamente mais viscosas do que as soluções de quitosana e obtiveram maior estabilidade térmica em solução na presença de sal em função dos grupos hidrofóbicos inseridos na estrutura da quitosanaCoordenação de Aperfeiçoamento de Pessoal de Nível Superiorapplication/pdfporUniversidade Federal do Rio Grande do NortePrograma de Pós-Graduação em QuímicaUFRNBRFísico-Química; QuímicaQuitosanaAlquilação redutivaGlutaraldeído3-Amino-1-propanolSolubilidadeComportamento reológicoChitosanReductive alkylationGlutaraldehyde3-Amino-1-propanolSolubilityRheological behaviorCNPQ::CIENCIAS EXATAS E DA TERRA::QUIMICAAlquilação redutiva da quitosana a partir do glutaraldeído e 3-amino-1-prReductive alkylation of chitosan by glutaraldehyde and 3-amino-1-propanolinfo:eu-repo/semantics/publishedVersioninfo:eu-repo/semantics/masterThesisinfo:eu-repo/semantics/embargoedAccessreponame:Repositório Institucional da UFRNinstname:Universidade Federal do Rio Grande do Norte (UFRN)instacron:UFRNORIGINALKeilaSA_DISSERT.pdfKeilaSA_DISSERT.pdfapplication/pdf2159921https://repositorio.ufrn.br/bitstream/123456789/17591/1/KeilaSA_DISSERT.pdfeaf4fb1bec7305fa007222908f6259acMD51KeilaSA_DISSERT_PARCIAL.pdfKeilaSA_DISSERT_PARCIAL.pdfapplication/pdf2160014https://repositorio.ufrn.br/bitstream/123456789/17591/2/KeilaSA_DISSERT_PARCIAL.pdf8cf16c698233ed8ab6d302c26172f81dMD52TEXTKeilaSA_DISSERT.pdf.txtKeilaSA_DISSERT.pdf.txtExtracted texttext/plain172972https://repositorio.ufrn.br/bitstream/123456789/17591/11/KeilaSA_DISSERT.pdf.txtfe06cd9556087071c7c640932ff25ecaMD511KeilaSA_DISSERT_PARCIAL.pdf.txtKeilaSA_DISSERT_PARCIAL.pdf.txtExtracted texttext/plain172972https://repositorio.ufrn.br/bitstream/123456789/17591/13/KeilaSA_DISSERT_PARCIAL.pdf.txtfe06cd9556087071c7c640932ff25ecaMD513THUMBNAILKeilaSA_DISSERT.pdf.jpgKeilaSA_DISSERT.pdf.jpgIM Thumbnailimage/jpeg4874https://repositorio.ufrn.br/bitstream/123456789/17591/12/KeilaSA_DISSERT.pdf.jpgd094ba4ea6abd167cc5f5f1e5e73a779MD512KeilaSA_DISSERT_PARCIAL.pdf.jpgKeilaSA_DISSERT_PARCIAL.pdf.jpgIM Thumbnailimage/jpeg4874https://repositorio.ufrn.br/bitstream/123456789/17591/14/KeilaSA_DISSERT_PARCIAL.pdf.jpgd094ba4ea6abd167cc5f5f1e5e73a779MD514123456789/175912017-11-04 11:00:32.583oai:https://repositorio.ufrn.br:123456789/17591Repositório de PublicaçõesPUBhttp://repositorio.ufrn.br/oai/opendoar:2017-11-04T14:00:32Repositório Institucional da UFRN - Universidade Federal do Rio Grande do Norte (UFRN)false |
dc.title.por.fl_str_mv |
Alquilação redutiva da quitosana a partir do glutaraldeído e 3-amino-1-pr |
dc.title.alternative.eng.fl_str_mv |
Reductive alkylation of chitosan by glutaraldehyde and 3-amino-1-propanol |
title |
Alquilação redutiva da quitosana a partir do glutaraldeído e 3-amino-1-pr |
spellingShingle |
Alquilação redutiva da quitosana a partir do glutaraldeído e 3-amino-1-pr Alves, Keila dos Santos Quitosana Alquilação redutiva Glutaraldeído 3-Amino-1-propanol Solubilidade Comportamento reológico Chitosan Reductive alkylation Glutaraldehyde 3-Amino-1-propanol Solubility Rheological behavior CNPQ::CIENCIAS EXATAS E DA TERRA::QUIMICA |
title_short |
Alquilação redutiva da quitosana a partir do glutaraldeído e 3-amino-1-pr |
title_full |
Alquilação redutiva da quitosana a partir do glutaraldeído e 3-amino-1-pr |
title_fullStr |
Alquilação redutiva da quitosana a partir do glutaraldeído e 3-amino-1-pr |
title_full_unstemmed |
Alquilação redutiva da quitosana a partir do glutaraldeído e 3-amino-1-pr |
title_sort |
Alquilação redutiva da quitosana a partir do glutaraldeído e 3-amino-1-pr |
author |
Alves, Keila dos Santos |
author_facet |
Alves, Keila dos Santos |
author_role |
author |
dc.contributor.authorID.por.fl_str_mv |
|
dc.contributor.advisorID.por.fl_str_mv |
|
dc.contributor.advisorLattes.por.fl_str_mv |
http://lattes.cnpq.br/7711521318854102 |
dc.contributor.referees1.pt_BR.fl_str_mv |
Delpech, Márcia Cerqueira |
dc.contributor.referees1ID.por.fl_str_mv |
|
dc.contributor.referees1Lattes.por.fl_str_mv |
http://lattes.cnpq.br/7492555701225765 |
dc.contributor.referees2.pt_BR.fl_str_mv |
Vidal, Rosângela Regia Lima |
dc.contributor.referees2ID.por.fl_str_mv |
|
dc.contributor.referees2Lattes.por.fl_str_mv |
http://lattes.cnpq.br/3249504806789438 |
dc.contributor.author.fl_str_mv |
Alves, Keila dos Santos |
dc.contributor.advisor1.fl_str_mv |
Balaban, Rosângela de Carvalho |
contributor_str_mv |
Balaban, Rosângela de Carvalho |
dc.subject.por.fl_str_mv |
Quitosana Alquilação redutiva Glutaraldeído 3-Amino-1-propanol Solubilidade Comportamento reológico |
topic |
Quitosana Alquilação redutiva Glutaraldeído 3-Amino-1-propanol Solubilidade Comportamento reológico Chitosan Reductive alkylation Glutaraldehyde 3-Amino-1-propanol Solubility Rheological behavior CNPQ::CIENCIAS EXATAS E DA TERRA::QUIMICA |
dc.subject.eng.fl_str_mv |
Chitosan Reductive alkylation Glutaraldehyde 3-Amino-1-propanol Solubility Rheological behavior |
dc.subject.cnpq.fl_str_mv |
CNPQ::CIENCIAS EXATAS E DA TERRA::QUIMICA |
description |
Chitosan derivatives were prepared by reductive alkylation using glutaraldehyde and 3-amino-1-propanol. The reducing agent used was the sodium borohydride. Tests of solubility, stability and viscosity were performed in order to evaluate these parameters effects in the reaction conditions (molar ratio of the reactants and presence of nitrogen in the reaction system). The molecular structure of commercial chitosan was determined by infrared (IR) and hydrogen nuclear magnetic resonance spectroscopy (1H NMR). The intrinsic viscosity and average molecular weight of the chitosan were determined by viscosimetry in 0.3 M acetic acid aqueous solution 0.2 M sodium acetate at 25 ºC. The derivatives of chitosan soluble in aqueous acidic medium were characterized by 1H NMR. The rheological behavior of the chitosan and of the derivative of chitosan (sample QV), which presented the largest viscosity, were studied as a function of polymer concentration, temperature and ionic strength of the medium. The results of characterization of the commercial chitosan (the degree of deacetylation obtained equal 78.45 %) used in this work confirmed a sample of low molar weight (Mv = 3.57 x 104 g/mol) and low viscosity (intrinsic viscosity = 213.56 mL/g). The chemical modification of the chitosan resulted in derivatives with thickening action. The spectra of 1H NMR of the soluble derivatives in acid aqueous medium suggested the presence of hydrophobic groups grafted into chitosan in function of the chemical modification. The solubility of the derivatives of chitosan in 0.25 M acetic acid aqueous solution decreased with increase of the molar ratio of the glutaraldehyde and 3-amino-1-propanol in relation to the chitosan. The presence of nitrogen and larger amount of reducing agent in reaction system contributed to the increase of the solubility, the stability and the viscosity of the systems. The viscosity of the polymeric suspensions in function of the shear rate increased significantly with polymer concentration, suggesting the formation of strong intermolecular associations. The chitosan presented pseudoplastic behavior with the increase in polymer concentration at a low shear rate. The derivative QV presented pseudoplastic behavior at all concentrations used and in a large range of shear rate. The viscosity of chitosan in solution decreased with an increase of the temperature and with the presence of salt. However, there was an increase of the viscosity of the chitosan solution at higher temperature (65 ºC) and ionic strength of the medium which were promoted by hydrophobic associating of the acetamide groups. The solutions of the chitosan derivatives (sample QV) were significantly more viscous than chitosan solution and showed higher thermal stability in the presence of salt as a function of the hydrophobic groups grafted into chitosan backbone |
publishDate |
2008 |
dc.date.issued.fl_str_mv |
2008-02-29 |
dc.date.available.fl_str_mv |
2009-03-10 2014-12-17T15:41:41Z |
dc.date.accessioned.fl_str_mv |
2014-12-17T15:41:41Z |
dc.type.status.fl_str_mv |
info:eu-repo/semantics/publishedVersion |
dc.type.driver.fl_str_mv |
info:eu-repo/semantics/masterThesis |
format |
masterThesis |
status_str |
publishedVersion |
dc.identifier.citation.fl_str_mv |
ALVES, Keila dos Santos. Reductive alkylation of chitosan by glutaraldehyde and 3-amino-1-propanol. 2008. 100 f. Dissertação (Mestrado em Físico-Química; Química) - Universidade Federal do Rio Grande do Norte, Natal, 2008. |
dc.identifier.uri.fl_str_mv |
https://repositorio.ufrn.br/jspui/handle/123456789/17591 |
identifier_str_mv |
ALVES, Keila dos Santos. Reductive alkylation of chitosan by glutaraldehyde and 3-amino-1-propanol. 2008. 100 f. Dissertação (Mestrado em Físico-Química; Química) - Universidade Federal do Rio Grande do Norte, Natal, 2008. |
url |
https://repositorio.ufrn.br/jspui/handle/123456789/17591 |
dc.language.iso.fl_str_mv |
por |
language |
por |
dc.rights.driver.fl_str_mv |
info:eu-repo/semantics/embargoedAccess |
eu_rights_str_mv |
embargoedAccess |
dc.format.none.fl_str_mv |
application/pdf |
dc.publisher.none.fl_str_mv |
Universidade Federal do Rio Grande do Norte |
dc.publisher.program.fl_str_mv |
Programa de Pós-Graduação em Química |
dc.publisher.initials.fl_str_mv |
UFRN |
dc.publisher.country.fl_str_mv |
BR |
dc.publisher.department.fl_str_mv |
Físico-Química; Química |
publisher.none.fl_str_mv |
Universidade Federal do Rio Grande do Norte |
dc.source.none.fl_str_mv |
reponame:Repositório Institucional da UFRN instname:Universidade Federal do Rio Grande do Norte (UFRN) instacron:UFRN |
instname_str |
Universidade Federal do Rio Grande do Norte (UFRN) |
instacron_str |
UFRN |
institution |
UFRN |
reponame_str |
Repositório Institucional da UFRN |
collection |
Repositório Institucional da UFRN |
bitstream.url.fl_str_mv |
https://repositorio.ufrn.br/bitstream/123456789/17591/1/KeilaSA_DISSERT.pdf https://repositorio.ufrn.br/bitstream/123456789/17591/2/KeilaSA_DISSERT_PARCIAL.pdf https://repositorio.ufrn.br/bitstream/123456789/17591/11/KeilaSA_DISSERT.pdf.txt https://repositorio.ufrn.br/bitstream/123456789/17591/13/KeilaSA_DISSERT_PARCIAL.pdf.txt https://repositorio.ufrn.br/bitstream/123456789/17591/12/KeilaSA_DISSERT.pdf.jpg https://repositorio.ufrn.br/bitstream/123456789/17591/14/KeilaSA_DISSERT_PARCIAL.pdf.jpg |
bitstream.checksum.fl_str_mv |
eaf4fb1bec7305fa007222908f6259ac 8cf16c698233ed8ab6d302c26172f81d fe06cd9556087071c7c640932ff25eca fe06cd9556087071c7c640932ff25eca d094ba4ea6abd167cc5f5f1e5e73a779 d094ba4ea6abd167cc5f5f1e5e73a779 |
bitstream.checksumAlgorithm.fl_str_mv |
MD5 MD5 MD5 MD5 MD5 MD5 |
repository.name.fl_str_mv |
Repositório Institucional da UFRN - Universidade Federal do Rio Grande do Norte (UFRN) |
repository.mail.fl_str_mv |
|
_version_ |
1802117735296008192 |