Hydration of carboxymethyl cellulose and carboxymethyl dextran

Koda, Shinobu; Hasegawa, Satoru; Mikuriya, Masumi; Kawaizumi, Fumio; Nomura, Hiroyasu

doi:10.1016/0032-3861(88)90188-7

Cited by 15 publications

(8 citation statements)

References 20 publications

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“…Furthermore, the effective diameter of a cellulose chain is somewhat larger because a glucose molecule does not lie in line but is somewhat tilted with respect to its adjacent unit. Our conclusion that the cross-section of CMC increases with ds is corroborated by findings reported by Koda et al From density measurements on aqueous CMC (ds = 0.56−2.85) solutions with different concentrations they calculated the apparent molar volume. Extrapolation of these data to zero concentration yields the partial molar volume of CMC.…”

Section: Resultssupporting

confidence: 91%

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Persistence Length of Carboxymethyl Cellulose As Evaluated from Size Exclusion Chromatography and Potentiometric Titrations

Hoogendam¹,

Keizer²,

Stuart³

et al. 1998

Macromolecules

144

132

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The intrinsic persistence length of carboxymethyl cellulose (CMC) is determined by size exclusion chromatography in combination with multiangle laser light scattering (SEC−MALLS) as well as from potentiometric titrations. Samples with degree of substitution (ds) ranging from 0.75 to 1.25 were investigated. The relation between molar mass M and radius of gyration R g as obtained by SEC−MALLS is determined in 0.02, 0.1, and 0.2 mol L-1 NaNO3. Using the electrostatic wormlike chain theory a bare (intrinsic) persistence length L p0 of CMC is assessed at 16 nm, irrespective of the degree of substitution. A somewhat lower value (12 nm) is obtained when Odijk's theory for the description of polyelectrolyte dimensions is applied. The difference between L p0 assessed from both models is discussed briefly. Potentiometric titrations were carried out in NaCl solutions (ranging from 0.01 to 1 mol L-1). From the titrations the radius of the CMC backbone was obtained by application of the model of a uniformly charged cylinder. The radius amounts to 0.95 nm for CMC ds = 0.75, and increases to 1.15 nm for CMC with ds = 1.25. The pK for the intrinsic dissociation constant of the carboxyl groups (i.e., at zero degree of dissociation) amounted to 3.2. L p0 was also deduced from potentiometric titrations. A model developed by Katchalsky and Lifson, which relates the dissociation behavior of a polyelectrolyte to the stiffness of its chain, was applied to CMC. From analyses of the potentiometric titrations an intrinsic persistence length of 6 nm was deduced. The difference between L p0 assessed from SEC−MALLS and potentiometric titrations is discussed briefly.

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Section: Resultssupporting

confidence: 91%

“…Extrapolation of these data to zero concentration yields the partial molar volume of CMC. The measurements in ref reveal an increase of the partial molar volume with increasing ds, which is related to an increase in the dimension of the CMC backbone.…”

Section: Resultsmentioning

confidence: 88%

Persistence Length of Carboxymethyl Cellulose As Evaluated from Size Exclusion Chromatography and Potentiometric Titrations

Hoogendam¹,

Keizer²,

Stuart³

et al. 1998

Macromolecules

144

132

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“…These values, consistent with previous literature for salt-free NaCMC with D.S. = 1.3, 82 are plotted in Figure 13 (c). The partial molar volume increases with salt concentration.…”

Section: Partial Molar Volume Of Polyelectrolytessupporting

confidence: 92%

Conformation and Phase Behavior of Sodium Carboxymethyl Cellulose in the Presence of Mono- and Divalent Salts

et al. 2020

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We report a small angle neutron scattering (SANS) study of semi-dilute aqueous solutions of sodium carboxymethyl cellulose (NaCMC), in the presence of mono-(Na +) and divalent salts (Mg 2+ , Ca 2+ , Zn 2+ , Ba 2+). A degree of substitution of 1.3 is selected to ensure that, in salt-free solution, the polymer is molecularly dissolved with conformation well described by polyelectrolyte scaling theory in semi-dilute regime. We find that Na + and Mg 2+ salt addition yield H-type phase behaviour, while Ca 2+ , Zn 2+ , and Ba 2+ instead yield L-type behaviour, in decreasing order of the salt concentration associated with demixing. Charge screening by addition of Na + induces the progressive disappearance of the characteristic polyelectrolyte correlation peak and eventually yields scattering profiles with a q −1 dependence over nearly three decades in wavenumber q. By fitting a descriptive model to data with excess Na + , we obtain a correlation length ξ'= 1030c −0.72 p [Å] with polymer concentration c p [g L −1 ]. Addition of Mg 2+ , which does not interact specifically with carboxylate groups, yields an analogous screening behaviour to that of Na + , albeit at lower salt concentrations, in line with its higher ionic strength. At low salt concentration, addition of specifically interacting Ca 2+ , Zn 2+ , and Ba 2+ yield a comparatively greater screening of the polyelectrolyte screening and, at concentrations above the phase boundary, results in excess scattering at low q, compatible with the formation of clusters of 10s nm in size. This behaviour is interpreted as due to the reduction in charge density along the chain, promoting association, clustering and eventual phase separation. Overall, drawing analogies with NaCMC at lower degree of substitution, where hydrophobic association takes place, our findings provide a framework to describe the solution conformation and phase behaviour of NaCMC in salt-free and salt solutions.

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“…This is confirmed with a linear regression correlation coefficient ( R 2 ) in the range of 0.99 to 0.93 for all datasets. Comparing the value of I 0 with the calculated one from the SLDs and partial molar volume of CMC, 64 we estimate the water content in the samples to be 14% for SANS 2D and 19% for the D11 and D22 samples, the difference arising possibly due to slightly different drying conditions and small errors in the absolute calibration of the neutron data. All the concentrations in this article are reported using the corrected concentration (assuming the water content to be 18% for the rheology samples).…”

Section: Resultsmentioning

confidence: 78%

Structure of sodium carboxymethyl cellulose aqueous solutions: A SANS and rheology study

Lopez

Rogers

Colby

et al. 2014

J Polym Sci B Polym Phys

160

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We report a small angle neutron scattering (SANS) and rheology study of cellulose derivative polyelectrolyte sodium carboxymethyl cellulose with a degree of substitution of 1.2. Using SANS, we establish that this polymer is molecularly dissolved in water with a locally stiff conformation with a stretching parameter. We determine the cross sectional radius of the chain ( 3.4 Å) and the scaling of the correlation length with concentration (ξ = 296 c−1/2Å for c in g/L) is found to remain unchanged from the semidilute to concentrated crossover as identified by rheology. Viscosity measurements are found to be in qualitative agreement with scaling theory predictions for flexible polyelectrolytes exhibiting semidilute unentangled and entangled regimes, followed by what appears to be a crossover to neutral polymer concentration dependence of viscosity at high concentrations. Yet those higher concentrations, in the concentrated regime defined by rheology, still exhibit a peak in the scattering function that indicates a correlation length that continues to scale as. © 2014 The Authors. Journal of Polymer Science Part B: Polymer Physics Published by Wiley Periodicals, Inc. J. Polym. Sci., Part B: Polym. Phys. 2015, 53, 492–501

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Hydration of carboxymethyl cellulose and carboxymethyl dextran

Cited by 15 publications

References 20 publications

Persistence Length of Carboxymethyl Cellulose As Evaluated from Size Exclusion Chromatography and Potentiometric Titrations

Persistence Length of Carboxymethyl Cellulose As Evaluated from Size Exclusion Chromatography and Potentiometric Titrations

Conformation and Phase Behavior of Sodium Carboxymethyl Cellulose in the Presence of Mono- and Divalent Salts

Structure of sodium carboxymethyl cellulose aqueous solutions: A SANS and rheology study

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