Comment on the Development of Particle Surface Charge Density during Surfactant-Free Emulsion Polymerization with Ionic Initiators

1998 ◽  
Vol 31 (26) ◽  
pp. 9390-9391 ◽  
Author(s):  
Klaus Tauer
Keyword(s):  
Charge Density ◽  
Surface Charge ◽  
Emulsion Polymerization ◽  
Surface Charge Density ◽  
Particle Surface

Effect of the particle surface charge density on the colloidal aggregation mechanism

1996 ◽  
Vol 53 (5) ◽  
pp. 4981-4989 ◽  
Author(s):  
A. Fernández-Barbero ◽  
M. Cabrerizo-Vílchez ◽  
R. Martínez-García ◽  
R. Hidalgo-Álvarez
Keyword(s):  
Charge Density ◽  
Surface Charge ◽  
Surface Charge Density ◽  
Particle Surface ◽  
Colloidal Aggregation ◽  
Aggregation Mechanism

scholarly journals Polystyrene latex particles obtained by emulsifier-free emulsion polymerization and their interaction with bentonite

e-Polymers ◽  
2011 ◽  
Vol 11 (1) ◽  
Author(s):  
Ioneta Codrina Bujanca ◽  
Mihai Cosmin Corobea ◽  
Florin Miculescu ◽  
Mihai Dimonie
Keyword(s):  
Charge Density ◽  
Surface Charge ◽  
Emulsion Polymerization ◽  
Surface Charge Density ◽  
High Surface ◽  
Polystyrene Latex ◽  
Sem Images ◽  
Latex Particles ◽  
Polystyrene Latex Particles ◽  
High Surface Charge Density

AbstractPolystyrene latex particles were prepared by using an emulsifier-free emulsion polymerization with two ionic initiators: potassium persulfate (KPS) and 2,2’-azobis(2-amidinopropane)dihydrochloride (AIBA). The purpose of this study was to obtain polystyrene latex with a good stability in time, a high surface charge density and a small particle size (between 100 and 1000 nm). We used two distinctive molar concentrations for both initiators: 5.5 mM and 55 mM based on aqueous phase. The analysis showed that in the case of KPS initiator the latexes stability was better. With AIBA as initiator smaller latex particles can be achieved. A high surface charge density was measured for large initiator concentration. We achieved satisfying results with both initiators, the optimal condition of polymerization depending on the subsequent utilization of the latex. The SEM images showed that latexes containing bentonite and latexes with no clay have similar size.

Nano ellipsoids at the fluid–fluid interface: effect of surface charge on adsorption, buckling and emulsification

2016 ◽  
Vol 186 ◽  
pp. 419-434 ◽  
Author(s):  
Venkateshwar Rao Dugyala ◽  
Thiriveni G. Anjali ◽  
Siliveru Upendar ◽  
Ethayaraja Mani ◽  
Madivala G. Basavaraj
Keyword(s):  
Charge Density ◽  
Surface Charge ◽  
Surface Charge Density ◽  
Particle Surface ◽  
Interfacial Properties ◽  
Fluid Interfaces ◽  
Particle Interactions ◽  
Kinetics Of Adsorption ◽  
Emulsion Drops

In this contribution, we discuss the role of surface charge on the adsorption of shape anisotropic particles to fluid–fluid interfaces in the context of their application in particle-stabilized emulsions. Starting with a pendent aqueous drop containing nano-ellipsoids of known surface charge density suspended in an oil medium, we study the kinetics of adsorption of the ellipsoids to the water–decane interface using pendant drop tensiometry. The interfacial tension of the drop is recorded as a function of time by analyzing the shape of the drop. We show that the particles that are weakly charged readily adsorb to the water–decane interface and the adsorption behavior is influenced by the particle surface charge density. Furthermore, as the area available for the particles deposited at the interface is reduced, the interface populated with self-assembled ellipsoids shows wrinkles indicating buckling of the particle-laden interface under compression. However, the buckling is not observed if nano-ellipsoids are highly charged confirming that the particles do not adsorb to the interface when they are highly charged. This suggests that in several examples where the particles at interfaces concept is exploited, the repulsive energy barrier due to the particle surface charge plays a key role in the adsorption of particles to the interfaces. However, once the particles are adsorbed, the interfacial properties of the monolayer depend on the particle–particle interactions. Thus a combination of these interactions determines the concentration of particles at the interface, their microstructure and interfacial properties. The effect of these interactions on the quantity and size of the emulsion drops stabilized by ellipsoidal particles is also explored.

scholarly journals ADSORPTION STUDIES IN A SYNTHETIC RUBBER LATEX-OVALBUMIN SYSTEM

1950 ◽  
Vol 34 (2) ◽  
pp. 183-192 ◽  
Author(s):  
H. B. Williams ◽  
A. R. Choppin
Keyword(s):  
Charge Density ◽  
Surface Charge ◽  
Surface Charge Density ◽  
Latex Particle ◽  
Particle Surface ◽  
Rubber Latex ◽  
Active Centers ◽  
Multilayer Adsorption ◽  
Synthetic Rubber ◽  
Synthetic Latex

1. Adsorption of ovalbumin on the latex surface was in excess of the quantity required to produce coverage of the surface over most of the protein concentrations range which was investigated. 2. "S" shaped isothermals which probably indicated multilayer adsorption were obtained. 3. The quantity of ovalbumin required to produce a constant surface charge density on the latex particle surface was a function of the pH, and a theory of active centers on the latex particles has been suggested. 4. A shift in the isoelectric point from that of native ovalbumin has been observed for the protein when adsorbed on a synthetic latex.

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