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Registros recuperados : 15 | |
3. | | LIMA, C. P. C. de; OSTER, A. H.; CAVALCANTI, F. R.; PAULA, R. C. M. de; FEITOSA, J. P. A. Induction of defense in apples by sulfated and deacetylated chichá gum. Polímeros, v. 31, n. 1, e2021010, p. 1-8, julho 2021. Biblioteca(s): Embrapa Uva e Vinho. |
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4. | | JUNIOR, C. P. A.; COAQUIRA, C. A. C.; SOUZA FILHO, M. de S. M. de; FEITOSA, J. P. A.; MORAIS, J. P. S.; ROSA, M. de F. Binderless Fiberboards Made from Unripe Coconut Husks. Waste and Biomass Valorization, v. 9, n. 11, p. 2245-2254, 2018. Biblioteca(s): Embrapa Agroindústria Tropical. |
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5. | | NASCIMENTO, D. M. do; NUNES, Y. N.; ALMEIDA, J. de; LEITAO, R. C.; FEITOSA, J. P. A.; DUFRESNE, A.; ROSA, M. de F. Development of an integrated process to produce CNFs and lignin and its potential applications for agrochemical delivery. Cellulose, v. 28, p. 10891-10904, 2021. Biblioteca(s): Embrapa Agroindústria Tropical. |
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6. | | NASCIMENTO, D. M.; ALMEIDA, J. S.; DIAS, A. F.; FIGUEIREDO, M. C. B. de; MORAIS, J. P. S.; FEITOSA, J. P. A.; ROSA, M. de F. A novel green approach for the preparation of cellulose nanowhiskers from white coir. Carbohydrate Polymers, v. 110, p. 456-463, 2014. Biblioteca(s): Embrapa Agroindústria Tropical. |
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7. | | PEREIRA, A. L. S.; NASCIMENTO, D. M. do; SOUZA FILHO, M. de S. M. de; MORAIS, J. P. S.; VASCONCELOS, N. F.; FEITOSA, J. P. A.; BRIGIDA, A. I. S.; ROSA, M. de F. Improvement of polyvinyl alcohol properties by adding nanocrystalline cellulose isolated from banana pseudostems. Carbohydrate Polymers, v. 112, p. 165-172, 2014. Biblioteca(s): Embrapa Agroindústria de Alimentos; Embrapa Agroindústria Tropical. |
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8. | | NASCIMENTO, D. M.; NUNES, Y. L.; FIGUEIREDO, M. C. B. de; AZEREDO, H. M. C. de; AOUADA, F. A.; FEITOSA, J. P. A.; ROSA, M. de F.; DUFRESNE, A. Nanocellulose nanocomposite hydrogels: technological and environmental issues. Green Chemistry, v. 20, p. 2428-2448, 2018. Biblioteca(s): Embrapa Agroindústria Tropical. |
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9. | | PEREIRA, A. L. S.; NASCIMENTO, D. M. do; SOUZA FILHO, M. de S. M. de; CASSALES, A. R.; MORAIS, J. P. S.; PAULA, R. C. M. de; ROSA, M. de F.; FEITOSA, J. P. A. Banana (Musa sp. cv. Pacovan) pseudostem fibers are composed of varying lignocellulosic composition throughout the diameter. Bioresources, v. 9, n. 4, p. 7749-7763, 2014. Biblioteca(s): Embrapa Agroindústria Tropical. |
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10. | | VASCONCELOS, N. F.; FEITOSA, J. P. A.; ANDRADE, F. K.; MIRANDA, M. A. R.; SASAKI, J. M.; MORAIS, J. P. S.; SILVA, L. M. A. e; CANUTO, K. M.; ROSA, M. de F. Chemically modified cellulose nanocrystals as polyanion for preparation of polyelectrolyte complex. Cellulose, v. 26, n. 3, p. 1725-1746, February 2019. Biblioteca(s): Embrapa Algodão. |
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11. | | DUARTE, E. B.; CHAGAS, B. S. DAS; ANDRADE, F. K.; BRIGIDA, A. I. S.; BORGES, M. de F.; MUNIZ, C. R.; SOUZA FILHO, M. de S. M. de; MORAIS, J. P. S.; FEITOSA, J. P. A.; ROSA, M. de F. Production of hydroxyapatite-bacterial cellulose nanocomposites from agroindustrial wastes. Cellulose, v. 22, n. 5, p. 3177-3187, 2015. Biblioteca(s): Embrapa Agroindústria de Alimentos; Embrapa Agroindústria Tropical. |
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12. | | DUARTE, E. B.; BORGES, M. de F.; SOUZA FILHO, M. de S. M. de; ANDRADE, F.; FEITOSA, J. P. A.; MUNIZ, C. R.; BRIGIDA, A. I. S.; MORAIS, J. P. S.; ROSA, M. de F. Obtenção de nanocompósitos de celulose bacteriana e hidroxiapatita a partir de resíduos agroindustriais. In: WORKSHOP DA REDE DE NANOTECNOLOGIA APLICADA AO AGRONEGÓCIO (REDE AGRONANO), 8., 2014, Juiz de Fora. Anais. Juiz de Fora: Embrapa Gado de Leite, 2014. Biblioteca(s): Embrapa Agroindústria Tropical. |
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13. | | DUARTE, E. B; CHAGAS, B. S. das; ANDRADE, F. K.; BRIGIDA, A. I. S.; BORGES, M. de F.; MUNIZ, C. R.; SOUZA FILHO, M. de S. M. de; MORAIS, J. P. S.; FEITOSA, J. P. A.; ROSA, M. de F. Utilização de resíduos agroindustriais na elaboração de bionanocompósitos baseados em celulose bacteriana e Hidroxiapatita. In: CONGRESSO BRASILEIRO DE POLÍMEROS, 13., 2015, Natal. Anais... São Carlos: ABPol, 2015. 5 p. Biblioteca(s): Embrapa Agroindústria Tropical. |
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14. | | DUARTE, E. B; CHAGAS, B. S. das; ANDRADE, F. K.; BRIGIDA, A. I. S.; BORGES, M. de F.; MUNIZ, C. R.; SOUZA FILHO, M. de S. M. de; MORAIS, J. P. S.; FEITOSA, J. P. A.; ROSA, M. de F. Utilização de resíduos agroindustriais na elaboração de bionanocompósitos baseados em celulose bacteriana e Hidroxiapatita. In: CONGRESSO BRASILEIRO DE POLÍMEROS, 13., 2015, Natal. [São Carlos: Associação Brasileira de Polímeros], 2015. 5 p. SP2.05.48. AK4X. Biblioteca(s): Embrapa Agroindústria de Alimentos. |
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15. | | BURITI, F. C. A.; SANTOS, K. M. O. dos; SOMBRA, V. G.; MACIEL, J. S.; SÁ, D. M. A. T.; SALLES, H. O.; OLIVEIRA, G.; PAULA, R. C. M. de; FEITOSA, J. P. A.; MOREIRA, A. C. O. M.; MOREIRA, R. A.; EGITO, A. S. do. Characterisation of partially hydrolysed galactomannan from Caesalpinia pulcherrima seeds as a potential dietary fibre. Food Hydrocolloids, v. 35, p. 512-521, March, 2014. Biblioteca(s): Embrapa Caprinos e Ovinos. |
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Registros recuperados : 15 | |
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Registro Completo
Biblioteca(s): |
Embrapa Algodão. |
Data corrente: |
14/01/2020 |
Data da última atualização: |
20/01/2020 |
Tipo da produção científica: |
Artigo em Periódico Indexado |
Circulação/Nível: |
A - 1 |
Autoria: |
VASCONCELOS, N. F.; FEITOSA, J. P. A.; ANDRADE, F. K.; MIRANDA, M. A. R.; SASAKI, J. M.; MORAIS, J. P. S.; SILVA, L. M. A. e; CANUTO, K. M.; ROSA, M. de F. |
Afiliação: |
Niédja Fittipaldi Vasconcelos, Universidade Federal do Ceará - UFC/Departamento de Química; Judith Pessoa Andrade Feitosa, Universidade Federal do Ceará - UFC/Departamento de Química; Fábia Karine Andrade, Universidade Federal do Ceará - UFC/Departamento de Engenharia Química; Marcus Aurélio Ribeiro Miranda, Universidade Federal do Ceará - UFC/Departamento de Física; José Marcos Sasaki, Universidade Federal do Ceará - UFC/Departamento de Física; JOAO PAULO SARAIVA MORAIS, CNPA; LORENA MARA ALEXANDRE E SILVA, CNPAT; KIRLEY MARQUES CANUTO, CNPAT; MORSYLEIDE DE FREITAS ROSA, CNPAT. |
Título: |
Chemically modified cellulose nanocrystals as polyanion for preparation of polyelectrolyte complex. |
Ano de publicação: |
2019 |
Fonte/Imprenta: |
Cellulose, v. 26, n. 3, p. 1725-1746, February 2019. |
Idioma: |
Inglês |
Conteúdo: |
Bacterial cellulose nanocrystals (BCNCs) have hydrophilic surfaces due to hydroxyl groups but are water-insoluble. The carboxymethylation improves the solubility of cellulose in polar media through the insertion of carboxymethyl groups. This study aims to evaluate the use of two different alcoholic solvents in the carboxymethylation reaction of BCNCs: ethanol and isopropanol. BCNCs were obtained under two hydrolysis conditions: sulfuric acid (BCNC-S) and combination of sulfuric and hydrochloric acids (BCNC-S/Cl). Two techniques (NMR and titration) were used to determine the degree of substitution (DS) values. Carboxymethylation of BCNC-S/Cl led to high DS compared to BCNC-S and the use of isopropanol promoted an even greater DS. The thermal properties were not affected after the chemical modification. However, functionalization provided an increase in the negative charge density at the surface of nanostructures and a change in the crystal structure (cellulose type Ia for amorphous), making this material a potential polyanion for the synthesis of polyelectrolyte complexes (PECs). The micrographs showed that the nanocrystals became soluble after carboxymethylation. Carboxymethylated bacterial cellulose nanocrystals hydrolyzed through the mixture of inorganic acids and modified using isopropanol (CBCNC-S/Cl-IPA) was a suitable polyanion to produce PECs with chitosan. The PECs produced had particle size ranging from 276 to 588 nm and zeta potential ranging from - 24.3 to + 39.0 mV. MenosBacterial cellulose nanocrystals (BCNCs) have hydrophilic surfaces due to hydroxyl groups but are water-insoluble. The carboxymethylation improves the solubility of cellulose in polar media through the insertion of carboxymethyl groups. This study aims to evaluate the use of two different alcoholic solvents in the carboxymethylation reaction of BCNCs: ethanol and isopropanol. BCNCs were obtained under two hydrolysis conditions: sulfuric acid (BCNC-S) and combination of sulfuric and hydrochloric acids (BCNC-S/Cl). Two techniques (NMR and titration) were used to determine the degree of substitution (DS) values. Carboxymethylation of BCNC-S/Cl led to high DS compared to BCNC-S and the use of isopropanol promoted an even greater DS. The thermal properties were not affected after the chemical modification. However, functionalization provided an increase in the negative charge density at the surface of nanostructures and a change in the crystal structure (cellulose type Ia for amorphous), making this material a potential polyanion for the synthesis of polyelectrolyte complexes (PECs). The micrographs showed that the nanocrystals became soluble after carboxymethylation. Carboxymethylated bacterial cellulose nanocrystals hydrolyzed through the mixture of inorganic acids and modified using isopropanol (CBCNC-S/Cl-IPA) was a suitable polyanion to produce PECs with chitosan. The PECs produced had particle size ranging from 276 to 588 nm and zeta potential ranging from - 24.3 to + 39.0 ... Mostrar Tudo |
Palavras-Chave: |
Carboxymethylation; Polyelectrolytic complexes. |
Thesaurus NAL: |
Chitosan; Hydrolysis; Nanocrystals. |
Categoria do assunto: |
-- |
URL: |
https://ainfo.cnptia.embrapa.br/digital/bitstream/item/208702/1/Chemically-modified-cellulose.pdf
|
Marc: |
LEADER 02321naa a2200277 a 4500 001 2118682 005 2020-01-20 008 2019 bl uuuu u00u1 u #d 100 1 $aVASCONCELOS, N. F. 245 $aChemically modified cellulose nanocrystals as polyanion for preparation of polyelectrolyte complex.$h[electronic resource] 260 $c2019 520 $aBacterial cellulose nanocrystals (BCNCs) have hydrophilic surfaces due to hydroxyl groups but are water-insoluble. The carboxymethylation improves the solubility of cellulose in polar media through the insertion of carboxymethyl groups. This study aims to evaluate the use of two different alcoholic solvents in the carboxymethylation reaction of BCNCs: ethanol and isopropanol. BCNCs were obtained under two hydrolysis conditions: sulfuric acid (BCNC-S) and combination of sulfuric and hydrochloric acids (BCNC-S/Cl). Two techniques (NMR and titration) were used to determine the degree of substitution (DS) values. Carboxymethylation of BCNC-S/Cl led to high DS compared to BCNC-S and the use of isopropanol promoted an even greater DS. The thermal properties were not affected after the chemical modification. However, functionalization provided an increase in the negative charge density at the surface of nanostructures and a change in the crystal structure (cellulose type Ia for amorphous), making this material a potential polyanion for the synthesis of polyelectrolyte complexes (PECs). The micrographs showed that the nanocrystals became soluble after carboxymethylation. Carboxymethylated bacterial cellulose nanocrystals hydrolyzed through the mixture of inorganic acids and modified using isopropanol (CBCNC-S/Cl-IPA) was a suitable polyanion to produce PECs with chitosan. The PECs produced had particle size ranging from 276 to 588 nm and zeta potential ranging from - 24.3 to + 39.0 mV. 650 $aChitosan 650 $aHydrolysis 650 $aNanocrystals 653 $aCarboxymethylation 653 $aPolyelectrolytic complexes 700 1 $aFEITOSA, J. P. A. 700 1 $aANDRADE, F. K. 700 1 $aMIRANDA, M. A. R. 700 1 $aSASAKI, J. M. 700 1 $aMORAIS, J. P. S. 700 1 $aSILVA, L. M. A. e 700 1 $aCANUTO, K. M. 700 1 $aROSA, M. de F. 773 $tCellulose$gv. 26, n. 3, p. 1725-1746, February 2019.
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