The Properties of Polymers in Solution. X. Ultrafiltrations of Rubber Solutions

1939 ◽  
Vol 12 (4) ◽  
pp. 774-777
Author(s):  
Kurt H. Meyer ◽  
Jean Jeannerat
Keyword(s):  
Colloidal Suspensions ◽  
Spherical Particles ◽  
Accurate Data ◽  
Colloidal Solutions ◽  
Dilute Solutions ◽  
Chain Molecules

Abstract It is a recognized fact that ultrafiltration is one of the most valuable methods for the study and treatment of colloidal suspensions formed of compact spherical particles. Not only is it possible to separate this type of particle from a solvent by means of a suitable ultrafilter, but it is also possible to determine the size of the particles by means of calibrated ultrafilters. Up to the present time, however, ultrafiltration has been utilized very little in the study of chain molecules, and no accurate data are available on the behavior of colloidal solutions of chain molecules during ultrafiltration. In the following discussion, the results of some experiments on the ultrafiltration of rubber solutions are described. Dilute solutions of rubber in toluene can be separated completely into rubber and solvent by ultrafiltration under pressure through fine ultrafilters with pores as fine as about 50 ḿ (“Fine” Cellafiltres and Membranfiltres). Solutions of crepe and solutions of masticated rubber give the same results.

scholarly journals Long-wavelength fluctuations and static correlations in quasi-2D colloidal suspensions

Soft Matter ◽  
2019 ◽  
Vol 15 (20) ◽  
pp. 4087-4097 ◽  
Author(s):  
Bo Zhang ◽  
Xiang Cheng
Keyword(s):  
Colloidal Suspensions ◽  
Spherical Particles ◽  
Long Wavelength

Dynamics of quasi-2D colloidal suspensions of binary spherical particles (left) and ellipsoids (right) under circular confinement.

Non-Spheric Colloidal Suspensions in Three-Dimensional Space

1997 ◽  
Vol 08 (04) ◽  
pp. 985-997 ◽  
Author(s):  
Dewei Qi
Keyword(s):  
Reynolds Number ◽  
Dimensional Space ◽  
Low Reynolds Number ◽  
Paper Industry ◽  
Three Dimensional ◽  
Colloidal Suspensions ◽  
Solid Particles ◽  
Spherical Particles ◽  
Dynamic Simulations ◽  
Low Reynolds

The translation and rotation of non-spherical particles, such as ellipsoidal, cylindric or disk-like pigment particles, in a Couette flow system similar to a blade coating system in the paper industry6 have been successfully simulated by using the lattice-Boltzmann method combined with Newtonian dynamic simulations. Hydrodynamic forces and torques are obtained by the use of boundary conditions which match the moving surface of solid particles. Then Euler equations have been integrated to include three-dimensional rotations of the suspensions by using four quaternion parameters as generalized coordinates. The three-dimensional rotations have been clearly observed. Consequently, the motion of the particles suspended in fluids of both low-Reynolds-number and finite-Reynolds-number, up to several hundreds, has been studied. It appears that the 3D translation and rotation of the non-spherical particles are more clearly observed in a high-Reynolds-number fluid than in a low-Reynolds-number fluid.

Influence of Oxygen Plasma Pretreatment on Fabricating PEI/TiO2/SiO2 Multilayer Films

2012 ◽  
Vol 441 ◽  
pp. 699-702 ◽  
Author(s):  
Yan Rong Jia ◽  
Jian Zhong Shao ◽  
Qin Guo Fan
Keyword(s):  
Plasma Treatment ◽  
Oxygen Plasma ◽  
Multilayer Films ◽  
Structural Color ◽  
Oxygen Plasma Treatment ◽  
Colloidal Solutions ◽  
Dilute Solutions ◽  
Substrate Pretreatment ◽  
Plasma Pretreatment ◽  
Quartz Substrates

In this work, we prepared PEI/TiO2/SiO2 multilayer films from the Polyethyleneimine (PEI) solution, TiO2 and SiO2 colloidal solutions. To investigate the influence of the substrate pretreatment, the multilayer films were fabricated on the quartz slides with or without oxygen plasma treatment. The SEM and AFM analyses indicated that PEI/TiO2/SiO2 multilayer films demonstrated low roughness and a uniform purple structural color on the oxygen plasma pretreated quartz substrates. The results showed that this technique could be used in fabricating multilayer films from dilute solutions.

THE SURFACE TENSION OF SLIGHTLY SOLUBLE FATTY ACIDS

1946 ◽  
Vol 24a (1) ◽  
pp. 8-14 ◽  
Author(s):  
D. G. Douglas ◽  
C. A. MacKay
Keyword(s):  
Fatty Acids ◽  
Surface Tension ◽  
Aqueous Solutions ◽  
Capillary Rise ◽  
Stable State ◽  
Melting Points ◽  
Considerable Time ◽  
Dilute Solutions ◽  
Chain Molecules ◽  
Capillary Rise Method

Surface tension measurements have been made on normal heptylic, pelargonic, capric, and lauric acids above their melting points and on aqueous solutions of heptylic, pelargonic, capric, and undecylic acids, at various concentrations. A modified capillary rise method was employed. The results indicate that the surface does not reach the stable state at once but requires considerable time, being slower for more dilute solutions and longer chain molecules. Evidence is given for the existence of a monolayer of closely packed molecules, with long axes perpendicular to the surface, each molecule occupying an area of approximately 25 Å for heptylic acid.

Dielectric relaxation in dilute solutions of polar chain molecules

1957 ◽  
Vol 23 (103) ◽  
pp. 211-221 ◽  
Author(s):  
L. K. H. Van Beek ◽  
J. J. Hermans
Keyword(s):  
Dielectric Relaxation ◽  
Dilute Solutions ◽  
Chain Molecules

Preparation of silver nanoparticles using atmospheric discharge plasma for catalytic reduction of p-nitrophenol: the influence of pressure in the reactor

2020 ◽  
Vol 49 (6) ◽  
pp. 449-456 ◽  
Author(s):  
Margarita Skiba ◽  
Viktoria Vorobyova ◽  
Alexander Pivovarov ◽  
Inna Trus
Keyword(s):  
Silver Nanoparticles ◽  
Discharge Plasma ◽  
Uv Spectroscopy ◽  
Spherical Particles ◽  
Colloidal Solutions ◽  
Ag Nps ◽  
Sem Images ◽  
Temperature Plasma ◽  
Content Type ◽  
Atmospheric Discharge

Purpose This paper aims to synthesize silver nanoparticles using atmospheric discharge plasma in contact with liquid at different pressure in reactor and to assess their catalytical properties for reducing 4-nanoparticles (NP). Design/methodology/approach The Ag colloidal NPs was rapidly synthesized as a result of non-equilibrium low-temperature plasma formation between an electrode and the surface of AgNO3 solution for 5 min at different pressure in reactor. Synthesized Ag NPs were characterized with common analytical techniques. Ultraviolet–visible (UV) spectroscopy, dynamic light scattering, scanning microcopy analysis were used to study the formation and characteristics of silver nanoparticles. Findings The formation of silver colloidal solutions under plasma discharge at different pressure in reactor is characterized by the presence of surface resonance peak in the spectra. Scanning electron microscope (SEM) images confirmed the formation of spherical particles having a size distribution in the range of 15-26 nm. The AgNPs solution showed excellent rapid catalytic activity for the complete degradation of toxic 4-nitrophenol (4-NPh) into non-toxic 4-aminophenol (4-APh) within 18 min. Research limitations/implications Further studies are necessary for confirmation of the practical application, especially of deposition Ag NPs on TiO2. Practical implications The method provides a simple and practical solution to improving the synthesis of colloidal solutions of Ag NPs for degradation of organic pollutants (4-NPh) in water and wasters water. Originality/value Atmospheric discharge plasma in contact with liquid at different pressure can be used as an effective technique for synthesis of nanomaterials with catalytic properties.

Isoprene and Rubber. Part 34. Molecules or Micelles in a Rubber Solution

1932 ◽  
Vol 5 (3) ◽  
pp. 265-277
Author(s):  
H. Staudinger ◽  
H. F. Bondy
Keyword(s):  
Colloidal Solutions ◽  
Dilute Solutions ◽  
Pure Nitrogen ◽  
Viscosity Measurements ◽  
Molecular Weights ◽  
Colloid Particles ◽  
Rubber Part ◽  
Complete Exclusion ◽  
The Individual ◽  
Viscous Solutions

Abstract Measurements of the Viscosity of Rubber Solutions In the literature may be found numerous measurements of the viscosity of rubber solutions, the object of which was to throw light on the nature of colloidal solutions and changes in these solutions by various operations. These investigations give no insight into the structure of colloid particles and the reason for changes in rubber solutions because they are based on false assumptions, particularly the assumption that rubber has a micellar structure. Often highly viscous solutions were studied, and though these appeared to be of special interest to the colloid chemist, they were unsuited for such investigations, for they are gel solutions in which the structure of the colloid particles is much more difficult to explain than is that in dilute solutions (sol solutions), where the molecules have freedom of movement and do not disturb one another. The earlier works also contain references to the sensitivity of rubber to oxygen, though no special precautions were ever taken in the measurements to exclude oxygen; in fact this was unnecessary as a rule, for crude rubber solutions are much more stable, because of anticatalysts present, than solutions of pure rubber in which these have been removed. Pure rubber was prepared by the method of Pummerer and Pahl and, as described in the following work, was separated by fractional extraction into portions of different average molecular weights. Viscosity measurements of the individual fractions were then carried out under various conditions. The study of the rubber solution, like that of the balata solution, must be carried out with complete exclusion of air, and the solvent (tetralin or benzene) must be distilled in an atmosphere of pure nitrogen and be freed of oxygen. The filtration of the rubber solution, the filling of the viscosimeter, as well as the measurements themselves, are likewise made in an atmosphere of pure nitrogen. Measurements were taken in the Ubbelohde viscosimeter at different pressures, as a rule at 10.30 and 60 cm. mercury pressure. Very dilute solutions were also measured in the Ostwald viscosimeter, since the deviations from the Hagen-Poiseuille law are of no great importance at low concentration. Finally, it should be mentioned that these special precautions during the viscosity measurements, above all the careful exclusion of air, are necessary only in the case of rubber, not with the saturated hydrocarbons, polystyrene, and hydrorubber.

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