Dispersion Technology

The most effective and widely used dispersants are low molecular weight anionic polymers. Dispersion technology has advanced to the point at which polymers are designed for specific classes of foulants or for a broad spectmm of materials. Acrylate-based polymers are widely used as dispersants. They have advanced from simple homopolymers of acryflc acid to more advanced copolymers and terpolymers. The performance characteristics of the acrylate polymers are a function of their molecular weight and stmcture, along with the types of monomeric units incorporated into the polymer backbone. 

Dispersion Technology. Substantial advancements in dispersion technology have been made since the initial introduction in 1923 of disperse dyes in paste form for cellulose acetate. Dyes were dissolved in sulfonated fatty acids such as sulforicinoleic acid [36634-48-7] (SRA),... 

One of the most important aspects of dispersion technology is the solid-liquid interphase. Interfacial phenomena determine to a large degree the physical characteristics of the final dispersion. 

P. J. D. and P. J.M. thank The UK Engineering and Physical Sciences Research Council, The European Commission, The Royal Society, ICI Paints, Unilever Research, Uniqema and Disperse Technologies for financial support. They acknowledge the considerable input and help of their colleagues, especially Dr. Paul Glover (University of Nottingham), Dr. Joe Keddie (University of Surrey) and Dr. Peter Aptaker (Laplacian Ltd.) in carrying out much of the work reviewed here. 

The interactions between similar particles, dissimilar particles, and the dispersion medium constitute a complex but essential part of dispersion technology. Such interparticle interactions include both attractive and repulsive forces. These forces depend upon the nature, size, and orientation of the species, as well as on the distance of separation between and among the particles of the dispersed phase and the dispersion medium, respectively. The balance between these forces determines the overall characteristics of the system. 

R. Neufeld and D. Poncelet, Industrial scale encapsulation of cells using emulsification/ dispersion technologies, in Fundamentals of Cell Immobilisation Biotechnology. Focus on Biotechnology Series, Vol. 8A, edited by V. Nedovic and R. Willaert (Kluwer Academic Publishers, Dordrecht, 2004), pp. 311-324. 

Dispersion technologies, USA (http //www. dispersion, com/) Felix Alba Associates (Scatterer.com) Scatterer Electro-acoustic spectroscopy Data interpretation software Particle sizing, zeta potential Particle size analysis No Yes... 

Plastisol is a specialized technique for making flexible vinyl products. It is also sometimes called paste or dispersion technology. Basically, powdered PVC is stirred into liquid plasticizer at room temperature to form a viscous liquid or spreadable paste. This can be poured or spread into the shape of the final product, heated to fuse, and cooled to gel into the final solid product. Simple pouring or gentle spreading require no heavy equipment, and do not damage delicate substrates such as... 

Given the potential consequences of inadequately dispersed pigments, pigment manufacturers apply proprietary surface treatments to make their products easier to disperse, and colorists who formulate with these pigments devote at least as much effort to dispersion technology as they do to color formulation technology. 

FFF is an analytical technique well deserving of a more widespread application at least in its most developed variants Fl-FFF, Th-FFF and S-FFF. Especially for complex colloidal or particulate matter, emulsion and dispersion technology, there are many advantages of FFF which certainly justify the implementation and research in most analytical laboratories dealing with such problems. 

Reis, C. P, Neufeld, R. J., Vile la, S., Ribeiro, A. J., and Veiga, F. (2006), Review and current status of emulsion/dispersion technology using an internal gelation process for the design of alginate particles, /. Microencapsul., 23(3), 245-257. 

Dukhin, S.A., Installation Handbook and User Manual Model DT-1200 Electroacoustic Spectrometer, Dispersion Technology Inc., Mount Kisco, NY, 2001. 

Table I shows the effect of crosslinker chain length and concentration on mechanical properties. Contrary to expectations, both flexural and impact properties increased slightly with increasing ethylene dimethacrylate (EDMA) content up to 10%. The crosslinker had a relatively slight effect on the stiffness and brittleness of the cured dispersions up to 15 vol %. Triethylene glycol dimethacrylate (TEDMA) behaved similarly but had a less favorable effect on impact strength. The 5 to 10% improvements in all mechanical properties at the 10% EDMA level compared with uncrosslinked dispersion might well offer a substantial improvement in functionality and durability under bioconditions if combined with other dispersion technology (1,2).

Dispersion Technology DT100 acoustic spectrometer. This instrument is a modern example of commerciai equipment which, in its basic design, foiiows the transmission tone-burst variabie gap technique pioneered by Andreae [101-103]. Figure 9.16A shows a photograph of a typicai unit. 

Figure 9.16. (A) The Dispersion Technology DT100 acoustic spectrometer. (B) Perspective and top views of the acoustic sensor. (Reproduced with permission of Elsevier, Ref [100].)...

A.S. Dukhin and RJ. Goetz, Ultrasound for Characterising Liquid Based Food Products. Dispersion Technology Inc. Publication, 1999. 

Pen Kem Acoustophor 8000 system (now Dispersion Technology) The system was extended for the measurement of sub-micron particle size distributions in concentrated slurries [238] which resulted in a prototype instrument, the Acoustophor Penn Kem 8000 system. This instrument consists of two flow-through cells for acoustic and electro-acoustic measurements respectively. With this system the acoustic attenuation is... 

Dispersion Technology DT-1200 combines the DT-100 with the DT-200 to give both size and zeta potential. Ultrasound induces a motion of particles relative to the liquid. This motion disturbs the double layer shifting a screening cloud of counter-ions. This displacement creates a dipole moment the sum of which creates an electric field that is measured by two electrode sensors. This field depends upon the value of the zeta potential which can be calculated using the appropriate theory. 

Dispersion Technology Inc., 3 Hillside Avenue, Mount Kisco, NY 10549, (914)241-4791, e-mail dispersi dispersion.com. 

Particle Sizing Systems, 75 Aero Camino, Santa Barbara, CA 93117, (805)968-1497Pascall Ltd, Gat wick Road, Crawley, Sussex, RHIO 2RS, UK Pascal Ltd.,Gatwick Road, Crawley, Sussex, RHIO 2RS, UK PenKem(now Dispersion Technology)... 

Application of Pseudo-Emulsion Based Hollow Fiber Strip Dispersion Technology in Metal Separation. 1059... 

APPLICATION OF PSEUDO-EMULSION BASED HOLLOW FIBER STRIP DISPERSION TECHNOLOGY IN METAL SEPARATION... 

Habib, M.J. Venkataram, S. Hussain, H.D. Fundamentals of solid dispersions. In Pharmaceutical Solid Dispersion Technology, Habib, M.J., Ed. Technomic Publishing Co., Inc. Lancaster, PA, 2001 7-35. 

Vendors of this technology include Sympatec GmbH (OPUS), Malvern Instruments Ltd. (Ultrasizer), Dispersion Technology Inc. (DT series), and Colloidal Dynamics Pty Ltd. (AcoustoSizer). 

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