scholarly journals Synthesis of chitosan and N-vinylimidazole graft-copolymers and the properties of their aqueous solutions

2021 ◽  
Vol 23 (4) ◽  
pp. 570-577
Author(s):  
Andrey V. Sorokin ◽  
Marina G. Kholyavka ◽  
Maria S. Lavlinskaya
Keyword(s):  
Aqueous Solutions ◽  
Ammonium Nitrate ◽  
Graft Copolymers ◽  
Gel Permeation Chromatography ◽  
Water Soluble ◽  
Ceric Ammonium Nitrate ◽  
Transmission Electron ◽  
Redox Initiator ◽  
Self Association ◽  
Stimuli Sensitive

The aim of this work is to synthesise chitosan and N-vinylimidazole graft-copolymers of various compositions and to study the properties of their aqueous solutions.Chitosan and N-vinylimidazole graft-copolymers were obtained by solution polymerisation in the presence of a ceric ammonium nitrate redox initiator. The synthesised graft copolymers were characterised by FTIR to determine their compositions and the grafted side chains of poly-N-vinylimidazole were characterised by gel permeation chromatography to determine their molecular wights and polydispersity indices. It was established that the obtained products are characterised by high values of yield and grafting efficiency and low values of the polydispersity index. It was found that when the content of the N-vinylimidazole links is above 57 wt%, the synthesised graft copolymers are water-soluble. Aqueous solutions of the obtained copolymers were characterised using dynamic light scattering, transmission electron microscopy, and laserDoppler microelectrophoresis. The study showed that macromolecules of graft copolymers in aqueous solutions have stimuli-sensitive properties with respect to the medium reaction and at a concentration above 10–2 wt% are characterised by a tendency to self-association forming core-crown aggregates, the geometry of which depends on the molecular masses of the grafted chains. Associates of macromolecules in solutions are characterised by positive values of the electrokinetic potential, the values of which also depend on the medium reaction. Thus, it was found that the ceric ammonium nitrate initiator allows obtaining chitosan and N-vinylimidazole graft-copolymers showing stimuli-sensitive properties in aqueous solutions and prone to self-association at concentrations above 10–2 wt%.

First approach on transfection ability of novel amphiphilic water soluble degradable poly(ε-caprolactone)-g-poly(Llysine) copolymers

e-Polymers ◽  
2008 ◽  
Vol 8 (1) ◽  
Author(s):  
Benjamin Nottelet ◽  
Julie Vendrell ◽  
Jean Coudane ◽  
Michel Vert
Keyword(s):  
Chemical Composition ◽  
Aqueous Solutions ◽  
Graft Copolymers ◽  
Water Soluble ◽  
Dna Transfection ◽  
Mcf 7

AbstractThe potential of novel amphiphilic water soluble and degradable poly(ε- caprolactone)-g-poly(L-lysine) as carriers for DNA transfection has been investigated. Two graft copolymers having the same proportion of lysine units but different structures have been synthesized following two grafting techniques. The chemical composition of these copolymers, their expected architectures and their behaviour in aqueous solutions have been studied. The benefits resulting from the use of these degradable polycationic structures as well as their ability to form polyplexes are discussed. Finally, preliminary transfection assays of MCF-7 cells by pRL-TK plasmid using poly(ε-caprolactone)-g-poly(L-lysine) copolymers as carriers are reported.

Graft copolymerization of methyl methacrylate onto sago starch using ceric ammonium nitrate and potassium persulfate as redox initiator systems

2002 ◽  
Vol 83 (10) ◽  
pp. 2275-2275
Author(s):  
Isam Y. M. Qudsieh ◽  
Wan Md Zin Wan Yunus ◽  
Fakhru'l-Razi A. ◽  
Mansor B. Ahmad ◽  
Mohamad Zaki Ab. Rahman
Keyword(s):  
Methyl Methacrylate ◽  
Ammonium Nitrate ◽  
Graft Copolymerization ◽  
Potassium Persulfate ◽  
Ceric Ammonium Nitrate ◽  
Sago Starch ◽  
Redox Initiator

The adsorption of quadrivalent cerium by kaolinite

Clay Minerals ◽  
1984 ◽  
Vol 19 (2) ◽  
pp. 137-149 ◽  
Author(s):  
F. Laufer ◽  
S. Yariv ◽  
M. Steinberg
Keyword(s):  
Aqueous Solutions ◽  
Ammonium Nitrate ◽  
Sulphuric Acid ◽  
Ceric Ammonium Nitrate ◽  
Equilibrium System ◽  
Monomeric Species ◽  
Clay Surface ◽  
Polymeric Species

AbstractThe adsorption of cerium(IV) by both natural and Na-exchanged kaolinite from aqueous solutions of ceric ammonium nitrate was studied in equilibrium systems. Cerium may be adsorbed either as a monomeric species or as a polymeric hydroxy cation. The species adsorbed depends on the concentration of cerium in the stock solution, the age of this solution prior to the preparation of the equilibrium system and on the equilibration period. Adsorbed cations undergo polymerization on the surface of the kaolinite; the resulting polymeric species forms strong bonds with the clay surface—it is not desorbed by sulphuric acid—and may be considered fixed. Adsorption of cerium reaches a maximum in solutions containing 0·15 M sulphuric acid.

Graft copolymerization of methyl methacrylate onto sago starch using ceric ammonium nitrate and potassium persulfate as redox initiator systems

2001 ◽  
Vol 82 (6) ◽  
pp. 1375-1381 ◽  
Author(s):  
A. Fakhru'L-Razi ◽  
Isam Y. M. Qudsieh ◽  
Wan Md Zin Wan Yunus ◽  
Mansor B. Ahmad ◽  
Mohamad Zaki Ab. Rahman
Keyword(s):  
Methyl Methacrylate ◽  
Ammonium Nitrate ◽  
Graft Copolymerization ◽  
Potassium Persulfate ◽  
Ceric Ammonium Nitrate ◽  
Sago Starch ◽  
Redox Initiator

scholarly journals Self-Association Behavior of Cell Membrane-Inspired Amphiphilic Random Copolymers in Water

Polymers ◽  
2019 ◽  
Vol 11 (2) ◽  
pp. 327 ◽  
Author(s):  
Maho Ohshio ◽  
Kazuhiko Ishihara ◽  
Shin-ichi Yusa
Keyword(s):  
Aqueous Solutions ◽  
Fluorescence Probe ◽  
Nmr Relaxation ◽  
Radical Copolymerization ◽  
Degree Of Polymerization ◽  
Water Soluble ◽  
Random Copolymers ◽  
Free Radical Copolymerization ◽  
Association Behavior ◽  
Self Association

Water-soluble and amphiphilic random copolymers (P(MPC/DMAx)) composed of hydrophilic 2-methacryloyloxyethyl phosphorylcholine (MPC) and hydrophobic n-dodecyl methacrylate (DMA) were prepared via reversible addition-fragmentation chain transfer (RAFT) controlled radical polymerization. The compositions of DMA unit (x) in the copolymer were in the range of 0 to 38 unit mol %. The degree of polymerization of P(MPC/DMAx) was adjusted to about 200. Since the monomer reactivity ratios of MPC and DMA are 1.01 and 1.00, respectively, ideal free radical copolymerization occurred. In aqueous solutions, interpolymer aggregation occurred due to the hydrophobic pendant n-dodecyl groups. The aggregation number (Nagg) increased with an increasing x. The mobilities of the DMA and MPC pendant groups in aqueous solutions were restricted, as confirmed by 1H NMR relaxation time measurements, because a part of the MPC units were trapped in the hydrophobic microdomain formed from the pendant n-dodecyl groups. The polarity of the hydrophobic microdomain formed from P(MPC/DMA38) in water was similar to that of ethyl acetate according to fluorescence probe experiments. No specific interactions were found in water between P(MPC/DMAx) and bovine serum albumin because the surface of the interpolymer aggregates contained only hydrophilic MPC units.

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