The structure of jets of water and polymer solution in air

1974 ◽  
Vol 63 (4) ◽  
pp. 635-640 ◽  
Author(s):  
J. W. Hoyt ◽  
J. J. Taylor ◽  
C. D. Runge

Jets of water and of poly(ethylene oxide) solutions discharging in air were photographed using a novel image-motion compensating camera. Spray droplet formation is inhibited by low concentration polymer solutions. The effect of the polymer is to reduce, dampen, or eliminate small-scale surface disturbances in the jet, while not reducing but even amplifying larger scale motions. The initial laminar zone present in the jet efflux with water is eliminated with trace quantities of polymer. When substantial quantities of polymer are present (200 p.p.m.), the jet breakup is accompanied by filament formation linking all the drops together.

Author(s):  
C. E. Cluthe ◽  
G. G. Cocks

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.


2003 ◽  
Vol 68 (10) ◽  
pp. 2019-2031 ◽  
Author(s):  
Markéta Zukalová ◽  
Jiří Rathouský ◽  
Arnošt Zukal

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.


2021 ◽  
Vol 594 ◽  
pp. 150-159
Author(s):  
Jure Cerar ◽  
Andrej Jamnik ◽  
István Szilágyi ◽  
Matija Tomšič

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