Thickening polymer

In addition to the normal problems of completely dissolving particles of water-thickening polymers, xanthan gum contains insoluble residues which decrease polymer injectivity. Various methods of reducing insolubles content and improving xanthan solution injectivity are available (80—87). None appears economically viable. Oxygen scavengers (88) and bactericides (77,89) are commonly used to stabili2e injected polyacrylamide and xanthan gum solutions (90—102). 

Surfactants evaluated in surfactant-enhanced alkaline flooding include internal olefin sulfonates (259,261), linear alkyl xylene sulfonates (262), petroleum sulfonates (262), alcohol ethoxysulfates (258,261,263), and alcohol ethoxylates/anionic surfactants (257). Water-thickening polymers, either xanthan or polyacrylamide, can reduce injected fluid mobiHty in alkaline flooding (264) and surfactant-enhanced alkaline flooding (259,263). The combined use of alkah, surfactant, and water-thickening polymer has been termed the alkaH—surfactant—polymer (ASP) process. Cross-linked polymers have been used to increase volumetric sweep efficiency of surfactant—polymer—alkaline agent formulations (265). 

Thickener polymers include polyurethanes, polyesters, polyacrylamides, natural polymers, and modified natural polymers [510]. 

Fluid loss additives such as solid particles and water-thickening polymers may be added to the drilling mud to reduce fluid loss from the well bore to the formation. Insoluble and partially soluble fluid loss additives include bentonite and other clays, starch from various sources, crushed walnut hulls, lignite treated with caustic or amines, resins of various types, gilsonite, benzoic acid flakes, and carefully sized particles of calcium borate, sodium borate, and mica. Soluble fluid loss additives include carboxymethyl cellulose (CMC), low molecular weight hydroxyethyl cellulose (HEC), carboxy-methYlhydroxyethyl cellulose (CMHEC), and sodium acrylate. A large number of water-soluble vinyl copolymers and terpolymers have been described as fluid loss additives for drilling and completion fluids in the patent literature. However, relatively few appear to be used in field operations. 

Both nonionic and anionic surfactants have been evaluated in this application (488,489) including internal olefin sulfonates (487, 490), linear alkylxylene sulfonates (490), petroleum sulfonates (491), alcohol ethoxysulfates (487,489,492). Ethoxylated alcohols have been added to some anionic surfactant formulations to improve interfacial properties (486). The use of water thickening polymers, either xanthan or polyacrylamide to reduce injected fluid mobility mobility has been proposed for both alkaline flooding (493) and surfactant enhanced alkaline flooding (492). Crosslinked polymers have been used to increase volumetric sweep efficiency of surfactant - polymer - alkaline agent formulations (493). 

Adsorption reactions on nonporous surfaces are generally quite rapid (unless there is a large activation energy barrier). By contrast, surface polymerization reactions are usually much slower. Thus it is likely that the initial high level of arises from adsorption, while the subsequent small, but continuous, increase in is caused by the thickening polymer film. 

Laun, H. M. Bung, R., and Schmidt, F. 1991. Rheology of extremely shear thickening polymer dispersions passively viscosity switching fluids. / Rheol. 35 999-1034. 

Figure 1.4 Network structure formed by an aqueous surfactant solution mixed with an associative thickening polymer hydroxyethylcellulose (HEC) with cetyl (16-carbon alkyl) side branches. (Reprinted from Clarke 1993, by courtesy of Marcel Dekker, Inc.)...

Aqueous concentrate of an associative thickening polymer, and use of a nonionic surfactant for reducing the viscosity of the concentrate... 

U.S. 5366653 (1994) [127] Corring (Lever Bros.) Dry-blending thickening polymer and sodium trimetaphosphate Concentrated liquid... 

Natural or modified polymers are often used as thickening or gelling agents, especially polysaccharides. Figure 6.1 gives examples of the effect of polymer concentration on apparent viscosity. Clearly, polysaccharides can be very effective thickeners. Polymers may be used to obtain a certain... 

Those factors that were previously mentioned that produce finer-textured foams also produce more stable foams. Factors such as surfactant type, concentration, increasing pressure, and higher inputs of mechanical energy generate more stable foams. For higher temperatures such as those that exist downhole, dynamic foam stability relies upon surfactant type and concentration rather than the addition of thickeners (polymer stabilizers). It is not known what rates are necessary to maintain dynamic stability in fractures, or whether those conditions typically exist. 

Among the carboxylic acid and anhydride functional monomers that have been employed in the synthesis of these thickener polymers are acrylic acid, methacrylic acid, itaconic acid, citraconic acid, maleic acid, fumaric acid, crotonic acid, maleic anhydride, and citraconic anhydride. The copolymers containing maleic and citraconic anhydride monomers are either hydrolyzed or partially esterified to obtain the required carboxyl functionality. Among these carboxylic monomers, maleic anhydride and particularly methacrylic acid are most frequently favored. Carboxylic homopolymers, where they can be formed, might be considered the simplest examples of ASTs were it not for the fact that they are not copolymers as defined, and some are water soluble in their un-ionized states. Examples of carboxylic homopolymers are the un-ionized free-radical-polymerized atactic forms of polyacrylic acid (i) and polymethacrylic acid (2), which are both readily soluble in water. 

What is understood by the term "traditional thickener" in general is a thickening agent which, when present in the coating, increases the viscosity of the aqueous phase and which do not significantly associate with the other ingredients. The polymer concentration at which polymer coils start to overlap is indicated by the critical polymer concentration (c ). Above this concentration, the viscosity is increased by a traditional thickener polymer dissolved in the aqueous phase, because of the entanglement of the polymer chains. (Fig. 1). 

Antibacterial and antifungal activities Thickening polymer Role on surfactant stability stabilize emulsion Make hair softer, increase mechanical strength Protecting elastic film on hairs, increasing their softness lacquers. Hair sprays Time release deliveries (chitosan beads, gels or granules)... 

Jarnstrom, L., Strom, G. and Stenius, P., The adsorption of dispersing and thickening polymers and their effect on the rheology of coating colors, Tappi /, 70, 101-107 (1987). 

Cellulose Hemicelluloses Fibres textile, paper, composites Derivatives methylcellulose, carboxymethylcellulose. Fibrous substrate Gelling and/or thickening polymers... 

Lambda (X) thickening polymer (polysaccharides extracted from Gigartina pistillata, Chondrus crispus). 

In order to improve production from waterflooding operations, various water-soluble thickening polymers are incorporated into the injection fluid (Mohanty and Caneba, 2005). The idea is that there is a need for a relatively high capillary number, Ac, in order to realize more efficient oil displacement from solid surfaces. Note that the capillary number is related to the displacing fluid viscosity, fx, interstitial velocity, V, and interfacial tension (IFT), y, (Pope and Baviere, 1991)... 

Synthetic polymers are ubiquitous in the personal care industry. Chapter 6 strives to address this rather broad topic in a straightforward and easily readable fashion. The chapter starts with a brief discussion of how synthetic polymers are made and the nomenclature used to describe some of the more basic structural principles of synthetic polymers. It expands to address many of the synthetic polymers used in personal care formulations based principally on their primary mode of operation, including thickening polymers, fixative polymers, conditioning polymers, and encapsulating polymers, the last subject becoming more important as formulators develop more sophisticated topical systems to deliver active materials. 

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