Dimerization of monofunctionalized poly(ethylene oxide) via metal–ligand interactions and hydrogen bonds

2004 ◽  
pp. 54-60 ◽  
Author(s):  
C. Tziatzios ◽  
D. Schubert ◽  
A. A. Precup ◽  
B. G. G. Lohmeijer ◽  
U. S. Schubert ◽  
...  
Keyword(s):  
Hydrogen Bonds ◽  
Ethylene Oxide ◽  
Ligand Interactions ◽  
Poly Ethylene Oxide ◽  
Poly Ethylene ◽  
Metal Ligand

scholarly journals Thermally responsive poly(ethylene oxide)-based polyrotaxanes bearing hydrogen-bonding pillar [5] arene rings

2020 ◽  
Author(s):  
Kenichi Kato ◽  
Katsuto Onishi ◽  
Koki Maeda ◽  
Masafumi Yagyu ◽  
Shixin Fa ◽  
...  
Keyword(s):  
Hydrogen Bonds ◽  
Ethylene Oxide ◽  
Water Solubility ◽  
Driving Forces ◽  
Mechanical And Thermal Properties ◽  
Oh Groups ◽  
Biological Compatibility ◽  
Poly Ethylene Oxide ◽  
Poly Ethylene ◽  
Multiple Hydrogen Bonds

Abstract Poly(ethylene oxide)s (PEOs) are useful polymers with good water solubility, biological compatibility, and commercial availability. In this study, PEOs with various end groups were threaded into pillar[5]arene rings in a mixture of water and methanol to afford pseudopolyrotaxanes. Multiple hydrogen bonds between the pillar[5]arene rings and hydrophobic–hydrophilic interactions between the ethylene groups of the PEOs and the hydrophobic pillar[5]arenes are the driving forces to form the pseudopolyrotaxane structure. Corresponding polyrotaxanes were also constructed by capping COOH-terminated pseudopolyrotaxanes with bulky amines, in which multiple hydrogen bonds involving the pillar[5]arene OH groups were critically important to prevent de-threading. The number of threaded ring components could be rationally controlled in these materials, providing a simple and versatile method to tune the mechanical and thermal properties. Specifically, a polyrotaxane with a high-molecular-weight axle became elastic upon heating above the melting point of PEOs and exhibited temperature-dependent shape memory property, because of the topological confinement and cross-linking by hydrogen bonds.

Temperature Effect on Hydrogen Bonds in Triblock Copolymers of Poly(Ethylene Oxide) and Polyacrylamide

2007 ◽  
Vol 468 (1) ◽  
pp. 53/[405]-61/[413] ◽  
Author(s):  
N. M. Permyakova ◽  
T. B. Zheltonozhskaya ◽  
S. V. Fedorchuk ◽  
N. E. Zagdanskaya ◽  
V. G. Syromyatnikov
Keyword(s):  
Hydrogen Bonds ◽  
Ethylene Oxide ◽  
Temperature Effect ◽  
Triblock Copolymers ◽  
Poly Ethylene Oxide ◽  
Poly Ethylene

The Structure of Radiation Cross-Linked Poly (ethylene oxide) Gels

1971 ◽  
Vol 29 ◽  
pp. 76-77
Author(s):  
C. E. Cluthe ◽  
G. G. Cocks
Keyword(s):  
Molecular Weight ◽  
Ethylene Oxide ◽  
Parallel Plate ◽  
Average Molecular Weight ◽  
Radical Reaction ◽  
Free Radical Reaction ◽  
Nitrogen Gas ◽  
Poly Ethylene Oxide ◽  
Poly Ethylene ◽  
Initial Viscosity

Aqueous solutions of a 1 weight-per cent poly (ethylene oxide) (PEO) were degassed under vacuum, transferred to a parallel plate viscometer under a nitrogen gas blanket, and exposed to Co60 gamma radiation. The Co60 source was rated at 4000 curies, and the dose ratewas 3.8x105 rads/hr. The poly (ethylene oxide) employed in the irradiations had an initial viscosity average molecular weight of 2.1 x 106.The solutions were gelled by a free radical reaction with dosages ranging from 5x104 rads to 4.8x106 rads.

Preparation of Organized Mesoporous Silica from Sodium Metasilicate Solutions in Alkaline Medium Using Nonionic Surfactants

2003 ◽  
Vol 68 (10) ◽  
pp. 2019-2031 ◽  
Author(s):  
Markéta Zukalová ◽  
Jiří Rathouský ◽  
Arnošt Zukal
Keyword(s):  
Mesoporous Silica ◽  
Ethylene Oxide ◽  
Sodium Metasilicate ◽  
Spherical Particles ◽  
Structure Directing Agent ◽  
Inorganic Species ◽  
Poly Ethylene Oxide ◽  
Acidic Conditions ◽  
Poly Ethylene ◽  
Hydrolysis Of

A new procedure has been developed, which is based on homogeneous precipitation of organized mesoporous silica from an aqueous solution of sodium metasilicate and a nonionic poly(ethylene oxide) surfactant serving as a structure-directing agent. The decrease in pH, which induces the polycondensation of silica, is achieved by hydrolysis of ethyl acetate. Owing to the complexation of Na+ cations by poly(ethylene oxide) segments, assembling of the mesostructure appears to occur under electrostatic control by the S0Na+I- pathway, where S0 and I- are surfactant and inorganic species, respectively. As the complexation of Na+ cations causes extended conformation of poly(ethylene oxide) segments, the pore size and pore volume of organized mesoporous silica increase in comparison with materials prepared under neutral or acidic conditions. The assembling of particles can be fully separated from their solidification, which results in the formation of highly regular spherical particles of mesoporous silica.

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