Dispersion in solvent

Pigment dispersions are stabilized by charge repulsion and entropic, ie, steric or osmotic, repulsion. Although both types of stabilization force may be present in most cases, for pigment dispersions in solvent-bome coatings entropic repulsion is usually the most important mechanism for stabilization. 

Particle-Size Distribution. Particle size, crystal shape, and distribution of vanillin are important and greatly affect parameters such as taste, flavor, solubility, case of dispersion in solvent, flowability of the powder, caking effect, and production of dust. 

Non-structural adhesives used on CELCXDN arc usually one-component, room-temperature-curing systems based either on thermoplastic resins or elastomeric materials dispersed in solvents. They are normally used in applications which will not be exposed to temperatures over 180°F. Neoprene rubber adhesives are examples. (7). 

IC50S (tearing) impacts from eye exposure to vapor from Tear Agents dispersed in solvents occur at concentrations as low as 0.15 mg/m (10 minute exposure). 

It is evident from these results, as well as from results cited later in this discussion, that the choice of solvent is of critical importance in achieving the best film properties from a resin system. The cheapest solvent combination may not and probably will not give best film properties. It is also evident that in the process of evaluating the merits of resins, conclusions could be erroneous unless the optimum solvent blend is chosen for each resin. Extrapolating these considerations further, it can be expected that the same resin could yield entirely different properties if it is applied to a surface in different forms, for example, as a solution, a dispersion in solvents, a dispersion in water, or as a powder. 

Svedberg s primary focus as a physical chemist was the field of colloid chemistry. Colloids are mixtures of very small particles that when dispersed in solvents are not dissolved, but are held in suspension by various actions of the solvent. Svedberg and his collaborators studied the interaction of colloid suspensions with light and their sedimentation processes. These studies showed that the gas laws could be applied to colloidal systems. Svedberg s Ph.D. thesis on the diffusion of platinum colloidal particles elicited a response from Albert Einstein, since it supported Einstein s theory concerning the Brownian motions of colloidal particles. 

When block and graft copolymers are dispersed in solvents, the solutions have properties that depend on whether or not the copolymer is eventually fully solvated. If the solvent is a good solvent for both sequences—for example, chloroform in the case of natural rubber graft copolymerized with poly(methyl methacrylate) (Halasa et al., 1976)—then both segment types are expanded and films cast from dilute solutions will usually be intermediate in properties to the... 

Chem. Descrip. Copolymer with acidic groups Uses Wetting agent, dispersant in solvent-based coatings, automotive/ OEM, industrial coatings, architectural paints, pigment cones., inks Features Exc. gloss and low haze in topcoats improves durability of wh. topcoats... 

Solution monomer dispersed in solvent with soluble catalyst free radical, ionic, Zeigler Nichols thermosets, acrylics, PVAlc, PVC, polybutadiene, polypropylene, melamine phenolic resins, polyisoprene, polycarbonate, chlorinated polyesters glass or s/s STR (2-8 kW/m mixen heat transfer area = 1-4 m /m depending on the volume of the reactor with small area associated with large volumes). 

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