Thickeners suspension stability

Uses O/w emulsifier, thickener, suspension stabilizer, lubricant, antitackifierfor cosmetics and phannaceuticals... 

The most common thickener is the circular basin type shown in Figure 7. After treatment with flocculant, the feed stream enters the central feed well which dissipates the stream s kinetic energy and disperses it gently into the thickener. The feed finds its height in the basin where its density matches the density of the inside suspension and spreads out at that level. Solids concentration increases downward in an operating thickener giving stability to the process. 

In addition to the above, there are emulsion and suspension stabilizers that act as protective colloids and in some cases as thickeners gums (such as acacia and traga canth), alginates, starch and starch derivatives, casein, glue, egg albumin, methyl cellulose, hydrated Mg and Al silicates, etc Refs Same as in previous item... 

Kollidon 30 is also used for this purpose. It can be combined with all conventional suspension stabilizers (thickeners, surfactants, etc.). 

Interest in these alkyl modifled polymeric structures was relatively low for some time, but about 20 years ago was heightened when it was realized that interalkyl chain association, as well as intrachain association, could take place, effectively increasing the molecular weight of the polymer and, therefore, the viscosity of the solution. Hence the term associative thickener evolved and now includes polyamphiphilic structures, i.e., not necessarily only polyionic structures. The presence of hydrophobic groups endows these polymers with surface and interfacial activity and hence with potential as foam, emulsion, and suspension stabilizers as well as surface conditioners. 

Surfactants and dispersants are used to disperse pigment, mineral and latex particles to promote suspension stability, to minimize the viscosity contribution of particle flocculation or agglomeration, and to enable higher solids content. Adjusting paint theology for optimal in-can stability and application properties normally requires the use of thickeners, thixotropes and rheology modifiers of various types. 

Mineral thixotropes - The mineral thixotropes are not used as the primary thickener in water-based coatings as their efficient is low compared to the polymers. They are,however, commonly used with conventional thickeners, particularly the cellulosics, to provide synergistic improvements in yield value (for suspension stabilization) and viscosity. Smectite and hormite cl s provide thixotropic aqueous dispersions and can impart a controlled degree of thixotropy to paints thickened with the conventional polymers. 

Uses Suspending agenL vise, builder, thickener, compatiblllzer, stabilizer in medicines, foods (ind. ice cream, juices), cosmetics (mousses) for suspensions, sol ns., emulsions bulking agent, filler, fiber supplement, thickener, stabilizer, sec. emulsifier, fat replacer In foods, ice cream, frozen desserts, salad dressings, drink mixes, lowfat and nonfat prods. 

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