Macroporous chelating resins incorporating heterocyclic functional groups via hydrophilic poly(ethylene oxide) spacer arms. II. Adsorption properties

2009 ◽  
Vol 111 (4) ◽  
pp. 2148-2156 ◽  
Author(s):  
Chunnuan Ji ◽  
Rongjun Qu ◽  
Qiang Xu ◽  
Changmei Sun ◽  
Chunhua Wang ◽  
...  
Keyword(s):  
Ethylene Oxide ◽  
Functional Groups ◽  
Adsorption Properties ◽  
Chelating Resins ◽  
Poly Ethylene Oxide ◽  
Poly Ethylene

Preparation of Gold Nanocrystals Having Various Morphologies under Polymeric Bulk Phase

2014 ◽  
Vol 548-549 ◽  
pp. 321-325
Author(s):  
Sang Ho Cha
Keyword(s):  
Ethylene Oxide ◽  
Functional Groups ◽  
Triblock Copolymer ◽  
Triblock Copolymers ◽  
Synthetic Approach ◽  
Gold Nanocrystals ◽  
Poly Ethylene Oxide ◽  
Poly Ethylene ◽  
Poly Propylene ◽  
Polymeric Template

A novel synthetic approach for gold nanocrystals using triblock copolymer as a polymeric template was described. The triblock copolymer used in this study was poly (ethylene oxide)20-poly (propylene oxide)70-poly (ethylene oxide)20 with hydroxy or thiol end-functional groups. The complexes of HAuCl4 and triblock copolymers were prepared by mixing and drying. After exposed to the sunlight for a few days, the gold nanocrystals, which have different sizes and shapes according to the ripening time, end functional groups, and gold salt concentrations, were obtained. The optical properties of the gold nanocrystals were also discussed.

Biodegradable copolymers based on poly(ethylene oxide), polylactide and polydepsipeptide sequences with functional groups

e-Polymers ◽  
2001 ◽  
Vol 1 (1) ◽  
Author(s):  
Yakai Feng ◽  
Doris Klee ◽  
Hartwig Höcker
Keyword(s):  
Block Copolymers ◽  
Ethylene Oxide ◽  
Aspartic Acid ◽  
Functional Groups ◽  
Ring Opening ◽  
Ring Opening Polymerization ◽  
Biodegradable Copolymers ◽  
Protective Groups ◽  
Poly Ethylene Oxide ◽  
Poly Ethylene

AbstractFor the purpose of increasing the hydrophilicity of polylactide, new block copolymers with protected functional groups, poly(lactide-co-(S)-b-benzyl aspartate)-poly(ethylene oxide)-poly(lactide-co-(S)- b-benzyl aspartate), were synthesized via ring-opening polymerization of D,L-lactide and (3S, 6R,S)-3- [(benzyloxycarbonyl)methyl]-6-methylmorpholine-2,5-dione in the presence of hydroxyltelechelic poly(ethylene oxide) (PEO) as an initiator at 140 °C for 24 h. The benzyl protective groups of the block copolymers were completely removed to give poly(lactide-co-(S)-aspartic acid)-PEO-poly(lactide-co-(S)-aspartic acid), (poly(DLLA-co-Asp)-b-PEO-b-poly(DLLA-co-Asp)). This shows lower crystallization and melting temperature compared with the polymers before deprotection. Poly(DLLA-co-Asp)-b-PEO-b-poly(DLLA-co-Asp) with 55.6 wt.-% of PEO is more hydrophilic, shows higher water absorption and is degraded faster than with 39.5 wt.-% of PEO.

From polymer to polyelectrolyte: Studies of star-branched poly(ethylene oxide) with lithium functional groups

2014 ◽  
Vol 115 ◽  
pp. 612-620 ◽  
Author(s):  
M. Marzantowicz ◽  
K. Pożyczka ◽  
M. Brzozowski ◽  
J.R. Dygas ◽  
F. Krok ◽  
...  
Keyword(s):  
Ethylene Oxide ◽  
Functional Groups ◽  
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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