A New Approach for Studying Correlations between the Chemical Structure and the Rheological Properties in Carboxymethyl Cellulose

Abstract

Two model sodium carboxymethyl celluloses (CMC) with similar monomer composition but with significant differences in the viscoelastic properties, that could not be assigned to variations in the average molar mass or molar mass distribution, were investigated with respect to the fraction of nonsubstituted cellulose segments in the polymers. The CMCs were hydrolyzed by a purified highly selective endoglucanase. The average molar mass and molar mass distribution of the enzyme products, as measured by size-exclusion chromatography with online multi-angle light scattering and refractive index detection (SEC/MALS/RI), revealed that the enzyme-catalyzed hydrolysis was more effective on one of the CMCs. To investigate whether this was due to a higher fraction of nonsubstituted cellulose segments in the polymer, the concentrations of nonsubstituted enzyme products, e.g., cellotetraose and cellopentaose, were measured by matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOFMS). It was concluded that the two CMCs displayed significant differences in the fraction of nonsubstituted cellulose segments. Furthermore, the CMC with the strongest attractive intermolecular interactions, according to rheometry, also contained the highest fraction of nonsubstituted cellulose segments.

Analysis of carbohydrates and glycoconjugates by matrix‐assisted laser desorption/ionization mass spectrometry: An update for 2007–2008

“…Correlation between chemical structure and rheological properties (Enebro, et al, 2007) Not stated Starch, pectic acid Hydrothermal, TOF Hydrothermal degradation of polysaccharides in a semi-batch reactor (Miyazawa, et al, 2008) anthracis. (Leoff, et al, 2008) Corynebacterium glutamicum Arabinogalactan R-TOF (DHB) Study of enzymology involved in biosynthesis (Meniche, et al, 2008) Equisetum arvense (horsetail) Cell walls TOF, Glycans (perMe)…”

Liquid chromatography combined with mass spectrometry for the investigation of endoglucanase selectivity on carboxymethyl cellulose

“…T. reesei endoglucanases have been applied for hydrolysis of cellulose derivatives in several recent studies. [4][5][6][11][12][13][14] The selectivity of the endoglucanases on various substrates was studied and interesting conclusions, based on the detection of specific enzyme products or the extent of the hydrolysis, were drawn.…”

Effects of dispersed medium systems on substitution pattern and solution performance of carboxymethyl cellulose

“…The unsubstituted segments or glucose residues in CMC molecules have the tendency of reciprocally binding with various levels in solutions [27]. In EtOH-IPA system, for the higher discrete degree of etherification zones in cellulose, longer unsubstituted segments may be arranged in molecular chains, resulting in the fact that certain amounts of molecules approach mutually and keep away from others, by which the configuration of aggregating units with a relatively discrete distribution in solution is formed, which not only causes the weakening of the network structure and the corresponding viscosity reduction but also, on the other side, integrally brings down the recovery extent of the solution structure under shear forces, leading to the decline of time dependence and thixotropy ( Fig.…”