Paints viscosity control

Paint Pigment, inert filler, viscosity control... 

Polyester paints with high solids contents (65-75 wt% at application viscosity) can be produced from very low molecular mass resins [2.95]. Low-pollution paints can also be produced from water-soluble polyester resins [2.85]. On account of their good water solubility, HMMM resins are particularly suitable for cross-linking these resins. Organic cosolvents (mostly glycol ethers) must be added to waterborne polyester paints to control their viscosity and applicability (leveling, substrate wetting). 

PEG-150 dIstearate, Trylox 5906 viscosity control agent, aq. paints/ coatings... 

The thickening and thixotropic effects in these classes of products attained with silica are too numerous to cite. Usually several effects are attained, namely, flatting or lower gloss, prevention of settling of pigment in storage, stabilization of emulsion, as well as dripless application. However, no information is available as to relative use of silicas versus other. thickeners in these products. Flatting seems to be the effect in paints and finishes most commonly mentioned in manufacturers bulletins. In inks, viscosity control is usually featured. 

Xanthan Xanthan gum is a polysaccharide secreted by the bacterium Xanthomonas campestiis It is composed of pentasaccharide repeat units, comprising glucose, mannose, and glucuronic acid in the molar ratio 2 2 1 In food industry for stabilization and gelling and viscosity control, in oil industry to enhance oil recovery, in the fabrication of tooth pastes and paints... 

Polystyrene, various Triglyceride oils Viscosity control, phase-separates during oil polymerization Oil-based house paints, makes coatings harder, tougher... 

Appiications antiblocking agent in plastic films, copying machines and laser printers (fluid control and prevention of static electricity), cosmetics (lipsticks, skin lotions, skin creams), paints and inks (moisture resistance, viscosity control) ... 

When a microgel is used as a viscosity controlling agent for a paint, a concentration that is much lower than close packing will show plastic or pseudoplastic flow. This is probably due to network formation by microgel aggregates. This structure is destroyed by shear but will reform when the shear is removed, showing a reversible nature. 

Fluidity of liquid compositions such as paints, inks, and adhesives influences handling during manufacturing and use, emulsification and stability of product shape, stickiness and appearance, and the properties of the final product. Microgels are widely used as viscosity controlling agents. 

In order to achieve a VOC-compliant coating, one must consider the molecular weight of the main binder utilized in the coating formulation, as well as the effect of additives on the final paint viscosity. After all, application viscosity, which in turn is affected by the rheology of the coating constituents, is most often controlled by freely adding solvent to achieve the necessary flow and leveling on the part. Addition of the solvent affects the final VOC emission of the paint. 

Uses Viscosity control agent in synthetic resin emulsion such as water-based emulsion paint, emulsion type adhesive thickener in civil engineering/building industry (cement, mortar), textile industry (printing paste), ceramic industry, paper-making... 

Technical uses are in - ceramics, where it aids green strength. M. acts as a flow and viscosity control in paints, and as an emulsifying and suspending agent in drilling muds. It is also used in chromatography. 

Emulsion Adhesives. The most widely used emulsion-based adhesive is that based upon poly(vinyl acetate)—poly(vinyl alcohol) copolymers formed by free-radical polymerization in an emulsion system. Poly(vinyl alcohol) is typically formed by hydrolysis of the poly(vinyl acetate). The properties of the emulsion are derived from the polymer employed in the polymerization as weU as from the system used to emulsify the polymer in water. The emulsion is stabilized by a combination of a surfactant plus a coUoid protection system. The protective coUoids are similar to those used paint (qv) to stabilize latex. For poly(vinyl acetate), the protective coUoids are isolated from natural gums and ceUulosic resins (carboxymethylceUulose or hydroxyethjdceUulose). The hydroHzed polymer may also be used. The physical properties of the poly(vinyl acetate) polymer can be modified by changing the co-monomer used in the polymerization. Any material which is free-radically active and participates in an emulsion polymerization can be employed. Plasticizers (qv), tackifiers, viscosity modifiers, solvents (added to coalesce the emulsion particles), fillers, humectants, and other materials are often added to the adhesive to meet specifications for the intended appHcation. Because the presence of foam in the bond line could decrease performance of the adhesion joint, agents that control the amount of air entrapped in an adhesive bond must be added. Biocides are also necessary many of the materials that are used to stabilize poly(vinyl acetate) emulsions are natural products. Poly(vinyl acetate) adhesives known as "white glue" or "carpenter s glue" are available under a number of different trade names. AppHcations are found mosdy in the area of adhesion to paper and wood (see Vinyl polymers). 

The main use of these clays is to control, or adjust, viscosity in nonaqueous systems. Organoclays can be dispersed in nonaqueous fluids to modify the viscosity of the fluid so that the fluid exhibits non-Newtonian thixotropic behavior. Important segments of this area are drilling fluids, greases (79,80), lubricants, and oil-based paints. The most used commercial products in this area are dimethyl di (hydrogen a ted tallow) alkylammonium chloride [61789-80-8] dimethyl (hydrogen a ted tallow)aLkylbenzylammonium chloride [61789-72-8] and methyldi(hydrogenated tallow)aLkylbenzylammonium chloride [68391-01-5]. 

Orifice. Orifice viscometers, also called efflux or cup viscometers, are commonly used to measure and control flow properties in the manufacture, processing, and appHcation of inks, paints, adhesives, and lubricating oils. Their design answered the need for simple, easy-to-operate viscometers in areas where precision and accuracy are not particularly important. In these situations knowledge of a tme viscosity is uimecessary, and the efflux time of a fixed volume of Hquid is a sufficient indication of the fluidity of the material. Examples of orifice viscometers include the Ford, Zahn, and Shell cups used for paints and inks and the Saybolt Universal and Furol instmments used for oils (Table 5). 

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