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Wöss K, Weber H, Grundnig P, Röder T, Weber HK. Rapid determination of γ-value and xanthate group distribution on viscose by liquid-state 1H NMR spectroscopy. Carbohydr Polym 2016; 141:184-9. [DOI: 10.1016/j.carbpol.2016.01.004] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2015] [Revised: 12/22/2015] [Accepted: 01/01/2016] [Indexed: 10/22/2022]
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Determination of the xanthate group distribution on viscose by liquid-state 1H NMR spectroscopy. Anal Bioanal Chem 2010; 400:2449-56. [DOI: 10.1007/s00216-010-4570-2] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2010] [Revised: 11/27/2010] [Accepted: 11/29/2010] [Indexed: 10/18/2022]
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Humeres E, Gerônimo VF, Zwirtes IR, Mazera E, Aliev AE. Supramolecular catalysis induced by polysaccharides. Homogeneous hydrolysis ofp-nitrobenzyl amylose xanthate. J PHYS ORG CHEM 2003. [DOI: 10.1002/poc.626] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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Humeres E, Sequinel LF, Nunes M, Oliveira CMS, Barrie PJ. Kinetic effects induced by cellulose on water-catalyzed reactions. Hydrolysis of 2,4-dinitrophenyl cellulose xanthate and some sugar xanthate ester analogues. CAN J CHEM 1998. [DOI: 10.1139/v98-046] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
The hydrolysis of 2,4-dinitrophenyl cellulose xanthate (CelXDNP) was studied in 10% v/v aqueous ethanol at 25°C and μ = 0.1 (KCl). The water-catalyzed hydrolysis showed that, as for p-nitrobenzyl cellulose xanthate, it occurs through two parallel reactions with rate constants k'H2O = 4.40 x 10-3 s-1 for the fast hydrolysis, and k''H2O = 6.90 x 10-5 s-1 for the slow hydrolysis. The entropy of activation of the fast hydrolysis was 0.7 ± 1.8 cal K-1 mol-1. External nucleophiles such as hydroxide and simple amines show simple first-order kinetics. The spontaneous hydrolysis of CelXDNP in acetone-water mixtures indicates that the fast reaction does not occur through water polymers and that for water molarity higher than 30 M there are no acetone molecules (or very few) in the highly ordered cybotactic region of cellulose. The spontaneous hydrolysis of methyl 4,6-O-benzylidene- α -D-glucopyranoside 3-(S-p-nitrobenzyl-xanthate) although is faster than the 6-isomer, it is slower than the fast hydrolysis of p-nitrobenzyl cellulose xanthate (CelXNB). Also Δ Sdouble dagger is highly negative (-41.0 cal K-1 mol-1), as it is for alkyl and sugar analogues. Only for the fast hydrolyses of CelXDNP and CelXNB is the entropy of activation almost zero. It is concluded that there is no neighbouring OH effect on the fast hydrolysis of cellulose xanthate esters. Key words: hydrolysis, water catalysis, cellulose xanthate esters, methyl glucose, xanthate esters, neighbouring OH effect.
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Humeres E, Sequinel LF, Nunes M, Oliveira CMS, Barrie PJ. Water-Catalysed hydrolysis ofp-nitrobenzyl cellulose xanthate. J PHYS ORG CHEM 1994. [DOI: 10.1002/poc.610070604] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
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Nehls I, Wagenknecht W, Philipp B, Stscherbina D. Characterization of cellulose and cellulose derivatives in solution by high resolution 13C-NMR spectroscopy. Prog Polym Sci 1994. [DOI: 10.1016/0079-6700(94)90037-x] [Citation(s) in RCA: 101] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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Iijima H, Kowsaka K, Kamide K. Determination of Sequence Distribution of Substituted and Unsubstituted Glucopyranose Units in Water-Soluble Cellulose Acetate Chain as Revealed by Enzymatic Degradation. Polym J 1992. [DOI: 10.1295/polymj.24.1077] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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Okajima K, Kowsaka K, Kamide K. An explanation of the solubility behaviour of cellulose acetate in various solvents in terms of supermolecular structure formed by introduction of a substituent group into the glucopyranose unit. POLYM INT 1992. [DOI: 10.1002/pi.4990290110] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
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Kowsaka K, Okajima K, Kamide K. Determination of the Distribution of Substituent Groups in Sodium Cellulose Sulfate: Assignment of 1H and 13C NMR Peaks by Two-Dimensional COSY and CH-COSY Methods. Polym J 1991. [DOI: 10.1295/polymj.23.823] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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Kowsaka K, Okajima K, Kamide K. Two-Dimensional Nuclear Magnetic Resonance Spectra of Cellulose and Cellulose Triacetate. Polym J 1988. [DOI: 10.1295/polymj.20.1091] [Citation(s) in RCA: 24] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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Kowsaka K, Okajima K, Kamide K. Determination of the Distribution of the Substituent Group in Cellulose Acetate by Full Assignment of Au Carbonyl Carbon Peaks of 13C{1H} NMR Spectra. Polym J 1988. [DOI: 10.1295/polymj.20.827] [Citation(s) in RCA: 26] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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