scholarly journals Viscoelasticity and Solution Stability of Cyanoethylcellulose with Different Molecular Weights in Aqueous Solution

Molecules ◽  
2021 ◽  
Vol 26 (11) ◽  
pp. 3201
Author(s):  
Qian Li ◽  
Yuehu Li ◽  
Zehua Jin ◽  
Yujie Li ◽  
Yifan Chen ◽  
...  
Keyword(s):  
Aqueous Solution ◽  
Sol Gel ◽  
Water Soluble ◽  
Effective Control ◽  
Solution Stability ◽  
Cellulose Ethers ◽  
Single Chain ◽  
Molecular Weights ◽  
Chain Complexes ◽  
Sol Gel Transition

Water-soluble cellulose ethers are widely used as stabilizers, thickeners, and viscosity modifiers in many industries. Understanding rheological behavior of the polymers is of great significance to the effective control of their applications. In this work, a series of cyanoethylcellulose (CEC) samples with different molecular weights were prepared with cellulose and acrylonitrile in NaOH/urea aqueous solution under the homogeneous reaction. The rheological properties of water-soluble CECs as a function of concentration and molecular weight were investigated using shear viscosity and dynamic rheological measurements. Viscoelastic behaviors have been successfully described by the Carreau model, the Ostwald-de-Waele equation, and the Cox–Merz rule. The entanglement concentrations were determined to be 0.6, 0.85, and 1.5 wt% for CEC-11, CEC-7, and CEC-3, respectively. All of the solutions exhibited viscous behavior rather than a clear sol-gel transition in all tested concentrations. The heterogeneous nature of CEC in an aqueous solution was determined from the Cox–Merz rule due to the coexistence of single chain complexes and aggregates. In addition, the CEC aqueous solutions showed good thermal and time stability, and the transition with temperature was reversible.

scholarly journals DYNAMICAL ASPECTS OF SOL-GEL TRANSITION IN AN AQUEOUS SOLUTION OF POLY (VINYL ALCOHOL)

1984 ◽  
Vol 40 (4-5) ◽  
pp. T158-T160
Author(s):  
Motoko Komatsu ◽  
Takashi Inoue ◽  
Keizo Miyasaka
Keyword(s):  
Aqueous Solution ◽  
Vinyl Alcohol ◽  
Sol Gel ◽  
Poly Vinyl Alcohol ◽  
Sol Gel Transition ◽  
Gel Transition

Dielectric behavior during sol-gel transition of PEO-PPO-PEO triblock copolymer aqueous solution

2000 ◽  
Vol 43 (6) ◽  
pp. 497-504 ◽  
Author(s):  
M. J. Song ◽  
D. S. Lee ◽  
J. H. Ahn ◽  
D. J. Kim ◽  
S. C. Kim
Keyword(s):  
Aqueous Solution ◽  
Triblock Copolymer ◽  
Sol Gel ◽  
Dielectric Behavior ◽  
Sol Gel Transition ◽  
Gel Transition

scholarly journals Synthesis and Investigation of Thermo-Induced Gelation of Partially Cross-Linked Poly-2-isopropyl-2-oxazoline in Aqueous Media

Polymers ◽  
2020 ◽  
Vol 12 (3) ◽  
pp. 698 ◽  
Author(s):  
Alina Amirova ◽  
Serafim Rodchenko ◽  
Mikhail Kurlykin ◽  
Andrey Tenkovtsev ◽  
Illia Krasnou ◽  
...  
Keyword(s):  
Self Assembly ◽  
Sol Gel ◽  
Aqueous Media ◽  
Water Soluble ◽  
Thermally Induced ◽  
Thermosensitive Gel ◽  
Step Procedure ◽  
Physical Gel ◽  
Sol Gel Transition ◽  
Gel Transition

Water-soluble, partially cross-linked poly-2-isopropyl-2-oxazoline combining the properties of chemical and physical gels was synthesized by a two-step procedure. Thermally induced sol-gel transition in its aqueous solution was studied by rheology, light scattering, and turbidimetry. It was demonstrated that the synthesized product is bimodal; it consists of linear and cross-linked components. The cross-linked components are responsible for the gelation, while the linear ones abate the viscosity growth. Heating the solution above the phase transition temperature leads to the self-assembly of the particles into a physical gel. The combination of chemical and physical cross-linking was found to be a prospective route for thermosensitive gel development.

Sol-gel transition behavior of biodegradable three-arm and four-arm star-shaped PLGA-PEG block copolymer aqueous solution

2005 ◽  
Vol 44 (2) ◽  
pp. 888-899 ◽  
Author(s):  
Su Jeong Lee ◽  
Bo Ryeong Han ◽  
Sang Yeob Park ◽  
Dong Keun Han ◽  
Sung Chul Kim
Keyword(s):  
Aqueous Solution ◽  
Block Copolymer ◽  
Sol Gel ◽  
Transition Behavior ◽  
Sol Gel Transition ◽  
Gel Transition

Binding of Pyrene to Cyclodextrin Polymers

1996 ◽  
Vol 50 (4) ◽  
pp. 511-516 ◽  
Author(s):  
T. C. Werner ◽  
Karen Colwell ◽  
Rezik A. Agbaria ◽  
Isiah M. Warner
Keyword(s):  
Polymer Chain ◽  
Gel Filtration ◽  
Water Soluble ◽  
Single Chain ◽  
Dramatic Decrease ◽  
Molecular Weights ◽  
Chromatography Analysis ◽  
Pyrene Fluorescence ◽  
Quencher Concentration ◽  
Rule Out

Polymers containing the three cyclodextrin (CD) molecules, α-CD, β-CD, and γ-CD, linked by epichlorohydrin (α-CDP, β-CDP, and γ-CDP) are highly water-soluble polydisperse mixtures containing CD units joined by repeating glyceryl linkers [-(CH2-CHOH-CH2-) n]. The average n value is 12-15, and gel filtration chromatography analysis indicates that the two major polymer components have molecular weights (MWs) of <2000 (1 CD/polymer chain) and 9-10,000 (4-5 CDs/polymer chain). We have used fluorescence properties to study the binding of pyrene to the three commercially available CDPs and to dialyzed samples of the CDPs, in which the low-MW (<2000, CDPL) and high-MW (9-10,000, CDPH) components have been separated. The pyrene emission I/III ratios for the three polymers are larger and exhibit a smaller range than the I/III ratios for the CD monomers. Moreover, the I/III ratio for the dialyzed polymers, β-CDPL and β-CDPH, are, within error, the same as that for β-CDP. It has been previously shown that additives, such as pentafluoropropanol (PFP), cause a dramatic decrease in the pyrene I/III ratio in the presence of β-CD. No effect on the pyrene I/III ratio is observed when these additives are added in the presence of the CDPs. The pyrene fluorescence decays in the presence of all three native polymers and the dialyzed β-CDPs are quite similar but different from the pyrene fluorescence decays in the presence of the three CD monomers. Moreover, the pyrene lifetimes show much greater dependence on iodide quencher concentration in the presence of CDPs than in the presence of β-CD and γ-CD. These data suggest that pyrene exists in a more exposed and hydrophilic environment when bound to the CDPs than that observed with the CDs. The agreement of the results for pyrene in the presence of β-CDP, β-CDPH, and β-CDPL would seem to rule out significant cooperative binding from two CD units on a single chain, which has previously been suggested. We conclude that pyrene binding to the CDPs may be largely noninclusional, involving considerable participation of the glyceryl linker units.

scholarly journals Diblock/Triblock Structural Transition and Sol-Gel Transition of Peptide/PEG Diblock Copolymer Having a Terminal Terpyridine Group Induced by Complexation with Metal Ion

2010 ◽  
Vol 2010 ◽  
pp. 1-6 ◽  
Author(s):  
Satoshi Tanimoto ◽  
Yasushi Nakamura ◽  
Hitoshi Yamaoka ◽  
Yoshitsugu Hirokawa
Keyword(s):  
Aqueous Solution ◽  
Light Scattering ◽  
Ring Opening ◽  
Metal Ion ◽  
Structural Transition ◽  
Sol Gel ◽  
Ring Opening Polymerization ◽  
The Other ◽  
Sol Gel Transition ◽  
Gel Transition

Terpyridine-polyethyleneglycol-block-polyleucine block copolymer (tpy-PEG-PLeu) was synthesized by a ring-opening polymerization of L-leucine -carboxyanhydride. The copolymer complexed with ion and its aqueous solution showed a purple color as a result of the complexation. This complexation caused the diblock/triblock structural transition of the copolymer. The change of the aggregation behavior caused by the structural transition was observed by a dynamic light scattering apparatus. The diblock tpy-PEG-PLeu copolymer formed a micelle in the aqueous solution. On the other hand, the triblock-type copolymer, after the complexation, formed the micelle structures and huge aggregates, which is considered to be a network structure. The complexation of the diblock tpy-PEG-PLeu copolymer with Fe ion is consequently considered to be a trigger of the gelation.

Fabrication of Self-Healable Hydrogels through Sol-Gel Transition in Metallo-supramolecular Aqueous Solution by Aeration

2013 ◽  
Vol 214 (22) ◽  
pp. 2534-2539 ◽  
Author(s):  
Taka-Aki Asoh ◽  
Haruka Yoshitake ◽  
Yota Takano ◽  
Akihiko Kikuchi
Keyword(s):  
Aqueous Solution ◽  
Sol Gel ◽  
Sol Gel Transition ◽  
Gel Transition
Sign in / Sign up

Export Citation Format

Share Document