Partially Acetylated Cellulose Dissolved in Aqueous Solution: Physical Properties and Enzymatic Hydrolysis

Cellulose acetate is one of the most important cellulose derivatives. The use of ionic liquids in cellulose processing was recently found to act both as a solvent and also as a reagent. A recent study showed that cellulose dissolution in the ionic liquid 1-ethyl-3-methylimidazoliumacetate (EMIMAc) mixed with dichloromethane (DCM) resulted in controlled homogenous cellulose acetylation; yielding water-soluble cellulose acetate (WSCA). This research investigated the properties of cellulose acetate prepared in this manner, in an aqueous solution. The results revealed that WSCA fully dissolves in water, with no significant sign of molecular aggregation. Its conformation in aqueous solution exhibited a very large persistence length, estimated as over 10 nm. The WSCA exhibited surface activity, significantly reducing the surface tension of water. Because of the molecular dissolution of WSCA in water, augmented by its amphiphilicity, aqueous solutions of WSCA exhibited an overwhelmingly high rate of enzymatic hydrolysis.

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Preparation of Lignosulfonates from Biorefinery Lignins by Sulfomethylation and Their Application as a Water Reducer for Concrete

Polymers ◽

10.3390/polym10080841 ◽

2018 ◽

Vol 10 (8) ◽

pp. 841 ◽

Cited By ~ 20

Author(s):

Caoxing Huang ◽

Junmei Ma ◽

Weiyu Zhang ◽

Guohong Huang ◽

Qiang Yong

Keyword(s):

Surface Tension ◽

Compressive Strength ◽

Enzymatic Hydrolysis ◽

Zeta Potential ◽

Water Soluble ◽

Water Soluble Polymer ◽

Potential Analysis ◽

Hydrolysis Residue ◽

Industrial Standards ◽

Zeta Potential Analysis

Lignosulfonate (LG), a water-soluble polymer from sulfite pulping process of lignocellulosic biomass, has been commercially applied as admixture for concrete. In this work, lignosulfonates were produced from alkaline lignin (AL) and enzymatic hydrolysis residue (EHR) by sulfomethylation and these lignosulfonates as water reducers for concrete were then evaluated. Results showed that 94.9% and 68.9% of lignins in AL and EHR could be sulfonated under optimum sulfomethylation conditions, respectively. The sulfonic groups in lignosulfonates from AL (AL-LG) and EHR (EHR-LG) were 1.6 mmol/g and 1.0 mmol/g, respectively. Surface tension and zeta potential analysis indicated that both AL-LG and EHR-LG can be potentially used to as dispersant for improving the fluidity of the cement paste, similarly to commercial lignosulfonate (CM-LG). Adding 0.2 wt % of AL-LG, EHR-LG, and CM-LG in the concrete, the compressive strength (28 days) of concretes increased from 38.4 Mpa to 41.6, 42.6, and 40.9 Mpa, respectively. These findings suggest that the lignosulfonate from biorefinery lignin by sulfomethylation can meet the industrial standards as water reducers for cement admixtures.

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On the characterization principles of some technically important water-soluble nonionic cellulose derivatives. Part II: Surface tension and interaction with a surfactant

Carbohydrate Polymers ◽

10.1016/0144-8617(96)00010-0 ◽

1996 ◽

Vol 29 (2) ◽

pp. 119-127 ◽

Cited By ~ 32

Author(s):

B Persson

Keyword(s):

Surface Tension ◽

Water Soluble ◽

Cellulose Derivatives

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Polymers as Ophthalmic Lubricating Agents

MRS Proceedings ◽

10.1557/proc-110-463 ◽

1987 ◽

Vol 110 ◽

Author(s):

S. Kalachandra ◽

D. O. Shah

Keyword(s):

Surface Tension ◽

Contact Angle ◽

Polymer Solutions ◽

Chemical Properties ◽

Surface Characteristics ◽

Water Soluble ◽

Cellulose Derivatives ◽

Water Soluble Polymer ◽

The Coefficient Of Friction ◽

Pmma Surface

AbstractPhysio-chemical properties such as coefficients of friction between low energy surfaces (PMMA/PMMA), surface tension, contact angle and viscosity of various water soluble polymer solutions ( 3–62cp) were measured at ambient temperature. The results showed that the surface tension and the contact angle are independent of viscosity of each polymer. The analysis of the data revealed that the system is operating in a region of “Boundary Lubrication”. It is seen, beyond 30 cp viscosity of almost all polymer solutions, the coefficient friction has been found to be independent of viscosity.Polyvinyl alcohol appears to have better lubricity in the vicinity of 30 cp viscosity or lower values than the cellulose derivatives and dextran. Hydrophobic interaction between PMMA surface and vinyl backbone may be responsible for this observation.It appears that the coefficient of friction of these polymer solutions depends on the structure, conformation and adsorption characteristics of polymers as well as surface characteristics of sliding surfaces, load, speed and viscosity.

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Concentration-dependent aggregation of water-soluble phosphorus porphyrin in an aqueous solution

Journal of Porphyrins and Phthalocyanines ◽

10.1142/s1088424612004471 ◽

2012 ◽

Vol 16 (02) ◽

pp. 210-217 ◽

Cited By ~ 7

Author(s):

Jin Matsumoto ◽

Shin-ichio Tanimura ◽

Tsutomu Shiragami ◽

Masahide Yasuda

Keyword(s):

Saccharomyces Cerevisiae ◽

Aqueous Solution ◽

Surface Tension ◽

Cell Wall ◽

Water Soluble ◽

The Other ◽

Measuring Surface ◽

Soluble Phosphorus ◽

Pass Through ◽

Low Passage

Water-soluble phosphorus tetraphenylporphyrins (1) were prepared by the introduction of axial polyoxaalkyloxo ligands (–O–(CH2CH2O)m–(CH2)n–H) . Bioaffinity of 1 for Saccharomyces cerevisiae was evaluated on the basis of the concentration (B A ) of 1 absorbed into the cells after they were immersed into an aqueous solution of 1 (10 μM). The behavior of 1 in the concentration range from 1 μM to 0.1 mM were estimated by measuring surface tension and absorption spectra and the behavior at a concentration of 1 mM were estimated by NMR spectroscopy. The 1 (m = 2, n = 4; m = 1, 2 and 3, n = 6) with a high B A of 123–171 mM were solved as monomers at 10 μM and could pass through the cell wall to accumulate inside the cell. Once inside the cell, where they reached a concentration of more than 10 μM, they formed aggregates that were unable to escape to the outside of the cell. On the other hand, it was found that 1 (m = 2 and 3, n = 1; m = 2, n = 2), whose B A values were <24 mM, did not form aggregates in the range from 1 μM to 1 mM; this indicated that they easily passed through the cell wall in both directions. In the case of 1 (m = 2 and 3, n = 12), whose B A values were low, passage through the cell wall was not possible because aggregates formed even at <1 μM.

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Enantioselective Recognition of Chiral Guests by the Water-Soluble Chiral Keplerate {Mo132} Spherical Capsule with 30 Inner Lactate Ligands

10.26434/chemrxiv.8847923.v1 ◽

2019 ◽

Author(s):

Nancy Watfa ◽

Weimin Xuan ◽

Zoe Sinclair ◽

Robert Pow ◽

Yousef Abul-Haija ◽

...

Keyword(s):

Aqueous Solution ◽

Chiral Recognition ◽

Association Constants ◽

Water Soluble ◽

Enantioselective Recognition ◽

H Nmr ◽

Dosy Nmr ◽

Spherical Capsule ◽

Surface Pores ◽

Guest Chemistry

Investigations of chiral host guest chemistry are important to explore recognition in confined environments. Here, by synthesizing water-soluble chiral porous nanocapsule based on the inorganic metal-oxo Keplerate-type cluster, {Mo132} with chiral lactate ligands with the composition [Mo132O372(H2O)72(x-Lactate)30]42- (x = D or L), it was possible to study the interaction with a chiral guest, L/D-carnitine and (R/S)-2-butanol in aqueous solution. The enantioselective recognition was studied by quantitative 1H NMR and 1H DOSY NMR which highlighted that the chiral recognition is regulated by two distinct sites. Differences in the association constants (K) of L- and D-carnitine, which, due to their charge, are generally restricted from entering the interior of the host, are observed, indicating that their recognition predominantly occurs at the surface pores of the structure. Conversely, a larger difference in association constants (KS/KR = 3) is observed for recognition within the capsule interior of (R)- and (S)-2-butanol.

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Sulfobetaine Cryogels for Preferential Adsorption of Methyl Orange from Mixed Dye Solutions

Polymers ◽

10.3390/polym13020208 ◽

2021 ◽

Vol 13 (2) ◽

pp. 208

Author(s):

Ramona B. J. Ihlenburg ◽

Anne-Catherine Lehnen ◽

Joachim Koetz ◽

Andreas Taubert

Keyword(s):

Aqueous Solution ◽

Methylene Blue ◽

Methyl Orange ◽

Dye Removal ◽

Selective Adsorption ◽

Water Soluble ◽

Organic Substances ◽

Preferential Adsorption ◽

Dimethyl Ammonium ◽

Dye Solutions

New cryogels for selective dye removal from aqueous solution were prepared by free radical polymerization from the highly water-soluble crosslinker N,N,N’,N’-tetramethyl-N,N’-bis(2-ethylmethacrylate)-propyl-1,3-diammonium dibromide and the sulfobetaine monomer 2-(N-3-sulfopropyl-N,N-dimethyl ammonium)ethyl methacrylate. The resulting white and opaque cryogels have micrometer sized pores with a smaller substructure. They adsorb methyl orange (MO) but not methylene blue (MB) from aqueous solution. Mixtures of MO and MB can be separated through selective adsorption of the MO to the cryogels while the MB remains in solution. The resulting cryogels are thus candidates for the removal of hazardous organic substances, as exemplified by MO and MB, from water. Clearly, it is possible that the cryogels are also potentially interesting for removal of other compounds such as pharmaceuticals or pesticides, but this must be investigated further.

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