Studies of concentrated polymer solutions by the fluorescence polarization method. I. Poly(ethylene oxide) in water

1967 ◽  
Vol 71 (8) ◽  
pp. 2416-2424 ◽  
Author(s):  
Hideaki Tanaka ◽  
Tomomi Yanagida ◽  
Akio Teramoto ◽  
Hiroshi Fujita
Keyword(s):  
Ethylene Oxide ◽  
Fluorescence Polarization ◽  
Polymer Solutions ◽  
Polarization Method ◽  
Poly Ethylene Oxide ◽  
Poly Ethylene

Effect of Polymer Additives on Jet Cavitation

1976 ◽  
Vol 98 (1) ◽  
pp. 106-111 ◽  
Author(s):  
J. W. Hoyt
Keyword(s):  
Ethylene Oxide ◽  
Polymer Solutions ◽  
Pure Water ◽  
Cavitation Inception ◽  
Air Content ◽  
Polymer Fluid ◽  
Water Value ◽  
Poly Ethylene Oxide ◽  
Poly Ethylene ◽  
Drag Reducing Polymer

Cavitation in a fluid jet discharged under the surface of a similar fluid was studied using water and dilute solutions of poly(ethylene oxide), a drag-reducing polymer. The addition of a few parts-per-million of poly(ethylene oxide) to the fluid reduced the cavitation-inception index to about one-half the pure-water value. Upstream turbulence increased the cavitation inception index with water but had little effect on cavitation inception with polymer solutions. The viscosity, air content, nuclei number, and tensile strength of the polymer fluid was found to be essentially the same as water, and the surface tension lowered; hence an explanation of the reduced cavitation-inception index observed in polymer solutions must be sought in the changed fluid dynamics of the polymer jet. Photographs of polymer jets discharging in air are presented to aid in the explanation.

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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