Viscosity-control additives

Polyacrylamides are used in many other oilfield appUcations. These include cement additives for fluid loss control in well cementing operations (127), viscosity control additives for drilling muds (128), and fracturing fluids (129). Copolymers [40623-73-2] of acrylamide and acrylamidomethylpropanesulfonic acid do not degrade with the high concentrations of acids used in acid fracturing. 

Examples of commonly used viscosity control additives are calcium ligno-sulfonate, sodium chloride and some long-chain polymers. These additives also act as accelerators or retarders so care must be taken in designing the cement slurry with these materials. 

Turner, S.R., Walker, T.O. and Thaler, W.A. "Sodium Styrene Sulfonate Co-Sodium N-(4-Sulfo Phenyl) Maleimide An Improved Viscosity Control Additive," US Patent 4,478,727(1984). 

Can be used as a nonionic emulsifier or coupling agent. It is used as a defoaraer in water base coatings, a viscosity depressant in vinyl plastisols, a viscosity control additive in hair rinse formulations, and as a paper softener. 

Danzik, M., Viscosity Control Additives for Foaming Mixtures in Petroleum Recovery., U.s. Patent No. 

These lipophilic members are used as emulsifiers and solubilizers for mineral oils, fats and solvents, as emulsifiers for kerosene and agricultural chemical sprays as emulsifiers in metal working fluids, Industrial lubricants and textile lubricants and as viscosity control additives in amphoteric toiletry preparations. 

Oil-soluble coemulsifier and lubricant in self-emulsifiable textile and industrial oils, mold release agent, viscosity control additive. 

Emulsifier, coupling agent defoamer in water-based coatings viscosity depressant in vinyl plastisols viscosity control additive in hair rinses paper softener. 

Drilling fluid viscosity control additive United States 3,332,872 1967 Monsanto... 

All of the eommereial alkyl eyanoaerylate monomers are low-viseosity liquids, and for some applications this can be an advantage. However, there are instances where a viseous liquid or a gel adhesive would be preferred, sueh as for application to a vertical surface or on porous substrates. A variety of viscosity control agents, depending upon the desired properties, have been added to increase the viscosity of instant adhesives [21]. The materials, which have been utilized, include polymethyl methacrylate, hydrophobic silica, hydrophobic alumina, treated quartz, polyethyl cyanoacrylate, cellulose esters, polycarbonates, and carbon black. For example, the addition of 5-10% of amorphous, non-crystalline, fumed silica to ethyl cyanoacrylate changes the monomer viscosity from a 2-cps liquid to a gelled material [22]. Because of the sensitivity of cyanoacrylate esters to basic materials, some additives require treatment with an acid to prevent premature gelation of the product. 

Commercial products are listed in the literature. These include bactericides, corrosion inhibitors, defoamers, emulsifiers, fluid loss and viscosity control agents, and shale control additives [58-61,65]. 

The viscosity of a cement affects the pumping properties. The viscosity must be kept low enough to ensure pumpability of the slurry during the entire operation period. In deep wells, because of the increased temperature, the viscosity becomes increasingly lower, which leads to undesirable flow characteristics of the slurry. This effect can be serious, because the viscosity follows the Arrhenius law. Some of the additives used for viscosity control also... 

A graphical representation of the viscosity of a system versus salt concentration. This curve can be an important characteristic of formulated systems in which viscosity control is necessary, such as in shampoo formulas. Solutions Salting in is when the addition of electrolyte to a solution causes an increase in the solubility of a specified solute. Salting out is when the addition of electrolyte causes a decrease in the solubility. 

The emulsification process is simple but must be carefully controlled. Epoxy resin is loaded into a high-speed disperser, and the surfactant is added. A defoamer is generally added to prevent excessive aeration, and high-shear mixing is employed. Water is then slowly added to the mixture. The system at this stage has the epoxy resin as the continuous phase and the water as the dispersed phase. As the water addition continues, the ratio of the dispersed phase to the continuous phase increases until a phase inversion occurs. The inversion occurs at about 65 percent volume ratio of dispersed to continuous phase and is accompanied by a rapid reduction in viscosity. Water addition is then continued until the desired solids concentration is achieved. Additional additives and modifiers can be incorporated into the formulation at this stage. 

Only these five will be described in detail in the following section, and simplified chemical structures of the four basic technologies are given in Fig. 5.1. Some VI improver compositions have pour point depression activity and/or dispersancy, in addition to their basic viscosity control properties. The former are described as appropriate in the following sections but are described in greater detail in Section 6.2. 

McGeehan, J.A. (1983) Effect of piston deposits, fuel sulphur, and lubricant viscosity on diesel engine od consumption and cylinder bore polishing. S7LE Trans. 92 Paper 831721. Texaco Inc. (1988) Diesel Lubricating Qd Consumption Control Additives . European... 

Thus, an increase in viscosity, leading to a reduced quenching rate constant (Equation 14.8), will result in an increased lifetime of the reactive intermediate (Equation 14.9). Depending on the nature of the diffusion-controlled reaction and the reactivity of the products formed, a rise in viscosity by addition of cosolvents like glycerol to the parenteral preparation can lead to improved or reduced photochemical... 

Viscosity control Some require external thickeners Thickened by addition of cosolvent Governed by polymer MW... 

OTHER COMMENTS used as a chemical intermediate in latex surface coating resins, in textile, dye and paper industries used as an oil additive for viscosity control, high pressure performance, and oxidation resistance use in rubber and pharmaceutical industries used in floc-culants in petroleum refining and in rocket propellant fuels. 

Although surface active agents, foam stabilizers, blowing agents, and viscosity control compounds are used as additives, the foams are primarily (90%) sulfur. 

Modifiers. A very large number of modifications in the cured and uncured properties of anaerobic formulations can be brought about by the addition of components that have little or no effect on the fundamental anaerobic cure chemistry. These modifiers can increase the viscosity, control thixotropy, add color or fluorescence, increase sealing effectiveness, reduce strength, increase toughness, increase heat resistance, provide lubrication, and reduce settling of fillers. 

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