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Matsumoto, Takayoshi; Tatsumi, Daisuke; Tamai, Naoto; Takaki, Tatsuya

doi:10.1023/a:1015162027350

Cited by 103 publications

(69 citation statements)

References 20 publications

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“…Interestingly, the solubility decreased almost linearly from 16 to 8 % (w/w) with increasing DP from 210 to 716 even though the solubility of cellulose with different molecular weight can not be compared precisely each other because of their different molecular weight distributions. Matsumoto et al 21 investigated the differences in the solubility and solution properties of celluloses from different biological origins such as plants, bacteria, and marine animals in LiCl/DMAc solvent. In the ethylenediamine/ NaSCN 54/46 (w/w) system, bacterial cellulose (DP2250) was also dissolved up to 5 % (w/w) maximum.…”

Section: Resultsmentioning

confidence: 99%

New Solvents for Cellulose. II. Ethylenediamine/Thiocyanate Salt System

Hattori

Abe

Yoshida

et al. 2004

Polym J

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ABSTRACT:The ethylenediamine/thiocyanate salt system was found to be a new solvent for cellulose. The solubility, dissolution behavior, solution properties, and cellulose recovered from the solutions were investigated. The dissolution took place at room temperature, and the maximum solubility achieved was 16 % (w/w) for cellulose of DP210 in the ethylenediamine/sodium thiocyanate 54/46 (w/w). The dependence of cellulose solubility on DP is also described. Tracing the dissolution behavior of the cellulose by CP/MAS 13 C NMR measurements revealed the polymorphic conversion of cellulose I to III to amorphous structure during the dissolution process. The cellulose dissolved was stable for 30 days storage at room temperature. Microscopic observations and steady-shear viscosity measurements of the solutions indicated mesophase formation of cellulose in the ethylenediamine/sodium thiocyanate system. This anisotrpoic phase appeared from ca. 10 % (w/w) cellulose with DP210 and greatly depended on the cellulose concentrations. Coagulation studies disclosed that cellulose II and amorphous cellulose were recovered from the cellulose/ethylenediamine/thiocyanate salt solutions when water and alcohol were used as a coagulant, respectively. It was suggested that this solvent system has high potential for cellulosic fiber and film formations.KEY WORDS Cellulose / Cellulose Solvent / Cellulose Solution / Amine / Thiocyanate / Dissolution Mechanism / Regenerated Cellulose / Cellulose is a linear and high molecular weight polymer as well as a natural, renewable, and biodegradable material. However, due to its considerable inter-and intramolecular hydrogen bonds, cellulose neither melts nor dissolves readily in common solvents. The complicated crystalline and amorphous morphology has also been preventing cellulose from being exploited to its fullest potential. Any process which simplifies or hastens the dissolution of cellulose represents a significant step forward in the development of cellulose as a viable, ecologically favorable polymer source. Furthermore, the ability of cellulose and cellulose derivatives to form mesophase in certain solvents has resulted in attempts to develop high-performance cellulosic fibers and membrane. At present, there are a few solvents that can directly dissolve cellulose without heavy metal complexation and any chemical derivatization, which are lithium chloride/dimethyl acetamide (LiCl/DMAc), 3 N-methylmorpholine-N-oxide/water (NMMO/H 2 O), 4 calcium thiocyanate/water (Ca(SCN) 2 /H 2 O), 5 etc. Quite recently, ionic liquids containing 1-butyl-3-methylimidazolium cations were discovered to dissolve high M w pulp (DP % 1000) with 10 % (w/w) at elevated temperatures. 6 However, almost known solvents still have some undesirable points, for example, chemical safety, environmental concern, degradation of cellulose, requirements of high temperatures and/or pretreatment of cellulose, poor mechanical properties of the cellulose recovered, and high cost for commercial use.We have been studied new solvent for ...

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Section: Resultsmentioning

confidence: 99%

New Solvents for Cellulose. II. Ethylenediamine/Thiocyanate Salt System

Hattori

Abe

Yoshida

et al. 2004

Polym J

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“…The models 10) for ordinary polymeric liquids should be applicable to those cellulose solutions. In fact, the molecularly dissolved cellulose solutions prepared from cotton behave very similarly to ordinary polymer solutions 1,7) , and this behavior can be explained by standard entanglement models (such as the reptation model 10) ) for polymeric liquids.…”

Section: Overviewmentioning

confidence: 98%

“…Recent discovery of solvents for cellulose [1][2][3][4][5] enables detailed molecular characterization, which has led to deeper understanding of the properties of pristine cellulose. Nevertheless, industrial application of cellulose is largely relying on processing of cellulose fiber suspensions in water, because these fibers are not molecularly dissolved in water and preserve their outstanding, pristine properties.…”

Section: Introductionmentioning

confidence: 99%

Rheology of Nano-Cellulose Fiber Suspension

Watanabe

Abe

Matsumura

et al. 2016

J. Soc. Rheol., Jpn

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Rheological behavior was examined for aqueous suspensions of nano-cellulose (NC) fibers. The plain-NC and carboxymethyl NC (CM-NC) fibers of an average diameter of ≅ 20 nm and a length of > 1 mm were used. These fibers had a curvy, multiple-branch (branch-on-branch) structure, and some of those branches were bundled into thicker trunks in particular for CM-NC, as revealed from TEM. Both plain-NC and CM-NC suspensions, having a low NC concentration of 0.62 wt%, exhibited essentially elastic behavior under small strain in the linear regime. This elastic behavior was attributable to elastic bending of the NC fibers that formed a mesh in the suspensions. Comparison of the elastic modulus data with the modified Doi-Kuzuu model prediction suggested that the curvy, multiple-branch structure of the NC fibers significantly increases effective contacts between the fibers thereby enhancing the elasticity, in particular for the plain-NC fiber having scarcer trunk portions compared to the CM-NC fiber. Corresponding to this origin of the enhanced elasticity, the suspensions exhibited significant nonlinearity under large amplitude oscillatory shear (LAOS) and steady shear flow. Namely, the modulus and steady state viscosity of the suspensions decreased roughly in proportion to reciprocal of the strain and shear rate, respectively, although strain-hardening was also noted for the CM-NC suspension under moderately small strains. This nonlinear decrease of the modulus and viscosity, phenomenologically classified as the yielding, would have resulted from strain/flow-induced slippage (decrease of the effective contacts) between the fibers.

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“…1) McCormick et al 2,3) first reported Mark-Houwink-Sakurada equation and molecular weight dependence of radius of gyration for cellulose in DMAc/LiCl. Matsumoto et al 4) used DMAc/LiCl to examine molecular weight of a few different cellulose by light scattering and also their viscoelastic properties. However, the dissolution process of cellulose/DMAc/LiCl takes very long time or requires high temperature as 150 °C so that more convenient solvents are still required.…”

Section: Introductionmentioning

confidence: 99%

Molecular Weight Estimation of Cellulose in Ionic Liquid Solution by Fitting Dynamic Viscoelastic Data to Rouse Model

Xü

Takahashi

2017

J. Soc. Rheol., Jpn

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As a molecular weight (M ) estimation method for cellulose in ionic liquid solution, fitting procedure of dynamic viscoelastic data to Rouse-Zimm (RZ) model with a correction term (LT term), introduced by Osaki et al. and examined for standard polystyrene samples, is examined in this study. Since the RZ model calculation with and without LT term for loss modulus G" almost coincide, the data are first fitted to RZ model to get the best fit of G" by using M as a single fitting parameter, while fixing other parameters from experimental conditions and using experimentally determined relaxation time t RZ . Then the LT term, calculated from intrinsic viscosity [h ] and two adjusting parameters, is employed to judge the appropriateness of the estimation of molecular weight by further fitting storage modulus G'. The measured G' and G" can be well fitted with RZ model plus LT term in the terminal region though small discrepancy in the transition region was observed. The estimated M showed ±10% error due to ±15% error of t RZ . It is concluded that this procedure is useful when t RZ can be determined within a small error. The estimated M can be used at least for the comparison of cellulose/IL solutions differently prepared.

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Untitled

Cited by 103 publications

References 20 publications

New Solvents for Cellulose. II. Ethylenediamine/Thiocyanate Salt System

New Solvents for Cellulose. II. Ethylenediamine/Thiocyanate Salt System

Rheology of Nano-Cellulose Fiber Suspension

Molecular Weight Estimation of Cellulose in Ionic Liquid Solution by Fitting Dynamic Viscoelastic Data to Rouse Model

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