scholarly journals Evaluation of the potential use of poly(ethylene oxide) as tablet- and extrudate-forming material

AAPS PharmSci ◽  
2004 ◽  
Vol 6 (2) ◽  
pp. 17-26 ◽  
Author(s):  
João F. Pinto ◽  
Kathrin F. Wunder ◽  
Andrea Okoloekwe
Keyword(s):  
Ethylene Oxide ◽  
Poly Ethylene Oxide ◽  
Poly Ethylene ◽  
Potential Use

New Hybrid Inorganic/Organic Block Copolymers as Templates for the Formation of Mesostructured Materials

2000 ◽  
Vol 628 ◽  
Author(s):  
Guido Kickelbick ◽  
Josef Bauer ◽  
Nicola Hüsing
Keyword(s):  
Block Copolymers ◽  
Ethylene Oxide ◽  
Inorganic Materials ◽  
Amphiphilic Block Copolymers ◽  
New Class ◽  
Mesostructured Silica ◽  
Mesostructured Materials ◽  
Poly Ethylene Oxide ◽  
Poly Ethylene ◽  
Potential Use

ABSTRACTAmphiphilic block copolymers were prepared with poly(dimethylsiloxane) (PDMS) as the hydrophobic unit. The hydrophilic block was composed of either a poly (ethylene oxide) or a functionalized polysiloxane unit. The polymer based on polysiloxane blocks only, represents one of the first examples of a new class of surfactants with a purely inorganic Si-O backbone. Beside their potential use as templates for the synthesis of mesostructured inorganic materials, these new polymers offer the possibility of being transformed into porous mesostructured silica-based material by controlled pyrolysis.

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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