Size Exclusion Chromatography of Cellulose and Cellulose Derivatives

Sj√∂holm, Elisabeth

doi:10.1201/9780203913321.ch12

Cited by 14 publications

(15 citation statements)

References 132 publications

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“…Unfortunately, an LS detector is not always available. Due to the lack of commercially available cellulose standards with narrow distribution, an alternative is calibration with the linear polysaccharide pullulan (maltotriose units which are linked α-1,6) [86,87,88]. SEC without absolute measurements can therefore give rise to a systematic error that is higher than a random error [28].…”

Section: How To Measure Molecular Weightsmentioning

confidence: 99%

Overview of Methods for the Direct Molar Mass Determination of Cellulose

2015

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Abstract:The purpose of this article is to provide the reader with an overview of the methods used to determine the molecular weights of cellulose. Methods that employ direct dissolution of the cellulose polymer are described; hence methods for investigating the molecular weight of cellulose in derivatized states, such as ethers or esters, only form a minor part of this review. Many of the methods described are primarily of historical interest since they have no use in modern cellulose chemistry. However, older methods, such as osmometry or ultracentrifuge experiments, were the first analytical methods used in polymer chemistry and continue to serve as sources of fundamental information (such as the cellulose structure in solution). The first part of the paper reviews methods, either absolute or relative, for the estimation of average molecular weights. Regardless of an absolute or relative approach, the outcome is a molecular weight average (MWA). In the final section, coupling methods are described. The primary benefit of performing a pre-separation step on the molecules is the discovery of the molecular weight distribution (MWD). Here, size exclusion chromatography (SEC) is unquestionably the most powerful and most commonly-applied method in modern laboratories and industrial settings.

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Section: How To Measure Molecular Weightsmentioning

confidence: 99%

Overview of Methods for the Direct Molar Mass Determination of Cellulose

2015

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“…Different values were obtained using SEC of non-derivatized cellulose in DMAc/LiCl and tricarbanilates of cellulose in THF (Dupont 2003;Dupont and Mortha 2004). Impact of cellulose derivatization on tricarbanilates as well as of solving of non-derivatized cellulose in DMAc/LiCl on changes of molecular weight are discussed in detail in several works and conclusions are again ambiguous (Danhelka et al 1976;Wood et al 1986;Potthast et al 2002;Sjöholm 2004;Henniges et al 2014).…”

Section: Resultsmentioning

confidence: 99%

Characterization of cellulose degradation during accelerated ageing by SEC-MALS, SEC-DAD, and A4F-MALS methods

Kačík

Podzimek²,

Vizárová

et al. 2015

Cellulose

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During their ageing, paper-based information carriers are subject to degradation, depending on the nature of the paper itself and conditions under which they are stored. Determination of the degree of polymerisation (DP) of the cellulose is most frequently used to evaluate the state of degradation and degradation kinetics. Their alterations affect the loss of mechanical properties of paper. Currently the most frequently used method of determination of the cellulose DP is the size exclusion chromatography (SEC), applied either to derivatized cellulose in form of tricarbanilates (CTC) or non-derivatized cellulose in the solution of lithium chloride in dimethylacetamide (LiCl/DMAc) or to solution of lithium chloride in 1,3dimethyl-2-imidazolidinone (LiCl/DMI). We have compared three methods of analysis of the cellulose isolated from paper which was subjected to accelerated ageing: size exclusion chromatography in combination with multi-angle light scattering (SEC-MALS) detection, size exclusion chromatography in combination with diode-array detector and calibration using polystyrene standards (SEC-DAD) and asymmetric flow field-flow fractionation in combination with multi-angle light scattering (A4F-MALS). Prior to separation, cellulose samples were derivatized with phenyl isocyanate to CTC and dissolved in tetrahydrofuran. Each of the used methods provides different absolute values of DP however pairwise correlations between them are linear with high correlation coefficients (r = 0.990 to 0.992). The highest DP values were obtained by the A4F-MALS method; SEC-MALS and SEC-DAD methods had lower values, especially due to shear degradation of high-molecular cellulose chains.

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“…Size exclusion chromatography (SEC) is an extremely useful type of analysis to characterize the polymer structure of cellulose. This method allows determine an important structural parameter, degree of polymerization (DP) that significantly influences the mechanical properties of cellulose [41]. According to paper [42], an increase in the DP of cellulose leads to an improvement in the strength properties of the fibers.…”

Section: Degree Of Cellulose Polymerization and Polydispersity Indexmentioning

confidence: 99%

Characterization of Manmade and Recycled Cellulosic Fibers for Their Application in Building Materials

Števulová¹,

Hospodárová²,

Estokova³

et al. 2019

Journal of Renewable Materials

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The aim of this study was to characterize two types of cellulosic fibers obtained from bleached wood pulp and unbleached recycled waste paper with different cellulose content (from 47.4 percent up to 82 percent), to compare and to analyze the potential use of the recycled fibers for building application, such as plastering mortar. Changes in the chemical composition, cellulose crystallinity and degree of polymerization of the fibers were found. The recycled fibers of lower quality showed heterogeneity in the fiber sizes (width and length), and they had greater surface roughness in comparison to high purity wood pulp samples. The high purity fibers (cellulose content > 80.0 percent) had greater crystallinity and more homogeneous and smooth surfaces than the recycled fibers. The presence of calcite and kaolinite in all of the recycled cellulosic fibers samples was confirmed, whereas only one wood pulp sample contained calcite. The influence of the chemical composition was reflected in the fiber density values. Changes in the chemical composition and cellulose structure of the fibers affected the specific surface area, porosity and thermo physical properties of the fibers. More favorable values of thermal conductivity were reached for the recycled fibers than for the wood pulp samples. Testing the suitability of the recycled fibers with inorganic impurities originating from the paper-making processes for their use as fillers in plastering mortars (0.5 wt.% fiber content of the total weight of the filler and binder) confirmed their application by achieving a compressive strength value of 28 day-cured fiber-cement mortar required by the standard as well as by measured more favorable value of capillary water absorption coefficient.

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Size Exclusion Chromatography of Cellulose and Cellulose Derivatives

Cited by 14 publications

References 132 publications

Overview of Methods for the Direct Molar Mass Determination of Cellulose

Overview of Methods for the Direct Molar Mass Determination of Cellulose

Characterization of cellulose degradation during accelerated ageing by SEC-MALS, SEC-DAD, and A4F-MALS methods

Characterization of Manmade and Recycled Cellulosic Fibers for Their Application in Building Materials

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