Viscosity water dispersion

Baked foods, instant foods, milk powders Salad dressings, release water-based flavor, colors Instant foods. Flavors Cosmetics and soaps, dyes, leather Oil soluble, water dispersible Oil soluble, water dispersible Easily sprayable, low viscosity, water dispersible - - - X X - X - - - X X - X - X X X... 

Hydantoin-Based Epoxy Resins. These resins were commercialized by Ciba-Geigy. Hydantoins are prepared from carbon dioxide, ammonia, hydrogen cyanide, and ketones via the Bucherer reaction and can be epoxidized with epichlorohydrin (67). Cured and imcured resin properties depend greatly on the nature of the substituents R and R. The hydantoin derived from acetone furnishes a low viscosity, water-dispersable epoxy resin, 5,5-dimethyl-l,3-bis(2,3-epoxypropyl)-2,4-imidazolidinedione (R = R = CH3 145 EEM rj at 25°C 2.5 Pa s). A nonsintering solid epoxy resin is obtained if R = R = —(CH2)5—. 

The process of flushing typically consists of the foUowing sequence phase transfer separation of aqueous phase vacuum dehydration of water trapped in the dispersed phase dispersion of the pigment in the oil phase by continued appHcation of shear thinning the heavy mass by addition of one or more vehicles to reduce the viscosity of dispersion and standardization of the finished dispersion to adjust the color and rheological properties to match the quaHty to the previously estabHshed standard. 

Almost all urethane materials are synthesized without the use of solvents or water as diluents or earners and are referred to as being 100% solids. This is true of all foams and elastomers. There are many products, however, which do utilize solvents or water, and these are known as solvent-borne and waterborne systems, respectively. In the past, many coatings, adhesives, and binders were formulated using a solvent to reduce viscosity and/or ease application. However, the use of volatile solvents has been dramatically curtailed in favor of more environmentally friendly water (see Section 4.1.3), and now there are many aqueous coatings, adhesives, and associated raw materials. Hydrophilic raw materials capable of being dispersed in water are called water reducible (or water dispersible), meaning they are sufficiently hydrophilic so as to be readily emulsified in water to form stable colloidal dispersions. 

Modem oil spill-dispersant formulations are concentrated blends of surface-active agents (surfactants) in a solvent carrier system. Surfactants are effective for lowering the interfacial tension of the oil slick and promoting and stabilizing oil-in-water dispersions. The solvent system has two key functions (1) to reduce the viscosity of the surfactant blend to allow efficient dispersant application and (2) to promote mixing and diffusion of the surfactant blend into the oil film [601]. 

We have already referred to the use of stabilisers in the production of water-dispersible flavourings and/or emulsion based cloudifying systems. Such additives, as well as contributing to stability, are also used, where appropriate, in soft drink formulations to impart stability to natural clouds, for example, dispersions of fruit solids, and to improve mouthfeel characteristics by increasing the viscosity of the dr ink. 

The saponification of a ceric-initiated starch-g-PAN was likwise examined at the different ethanol-water ratios, and these results are also shown in Table III. Once again, solubilities were determined for undried water dispersions after exhaustive dialysis. Brookfield viscosity was not used as a measure of crosslinking for these HSPAN preparations, because individual gel particles could not absorb all of the available water at 0.22% solids and thus could not exist in... 

The second soluble starch-g-PAN (No. 3) was prepared by subjecting another starch graft copolymer to a mild acid hydrolysis to partially depolymerize the starch moiety. The ethanol-water solvent system apparently promotes a greater number of starch PAN crosslinks than water, as evidenced by the lower solubilities (45 vs. 71% and 42 vs. 65%) and the higher viscosities for water dispersions (2400 vs. 920 cp and 690 vs. 

Radiation radiation, depending on wavelength and dose, has been shown to have a variety of effects, including increased gelatinization temperature, improved stability and reduced viscosity, swelling power and enzyme susceptibility. Radiation has also been used to promote chemical modification. Marquette et al.118 have a patent for microwaving starch to improve rheological stability and hot water dispersibility. They... 

An initial negative slope of iq, vs ct in a dilute water dispersion (electroviscosity) of a polysaccharide is indicative of polyanionic character. Electroviscosity disappears in excess electrolyte solution and is nonexistent in neutral polymer viscosity profiles. 

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. 

Fig. 39. Apparent viscosity of dispersions of silica (2a = 2 nm) in 0.5 wt% solutions of polyacrylamide (Mw = 5.5 x 103 kg/mol) in 50/50 glycerin-water mixtures (Otsubo and Watanabe, 1987). Different symbols correspond to different weight percentages of silica.

Reduction (sulfite) Reduced viscosity of water dispersion increased viscosity in salt solution and resistance to aggregation ... 

Achayuthakan et al. (2006) studied vane yield stress of Xanthan gum-stareh dispersions. The intrinsic viscosity of Xanthan gum was determined to be 112.3 dl/g in distilled water at 25°C. In addition, the size of the granules in the dispersions of the studied starches waxy maize (WXM), cross-linked waxy maize (CWM), and cold water swelling (CWS) were determined. The values of yield stress of the starch-xanthan dispersions relative to those of the starch-water dispersions (YSA"S0) and relative mean granule diameters (D/DO) plotted against values of c[ ] of xanthan gum are shown in Figure 4-42. With the values of YS/YSO being less than 1.0, there was no synergism between CLWM starch and xanthan gum. 

Easily sprayable, low viscosity, oil soluble Low flavor Water dispersible Dry blendable, oil soluble, water dispersible, low flavor... 

Figure 7.12 Shear-stress dependence of the relative viscosity for dispersions in water of charged polystyrene particles of radius a = 115 nm with nonadsorbing Dextran T-500 polymer (synthesized from glucose) added as a depletion flocculant. The polymer molecular weight is 298,(HX), and its radius of gyration Rg is 15.8 nm. Volume fractions and polymer concentrations are

Water-dispersible Low viscosity low odour non-flammable easy to clean good adhesion, especially to damp concrete good abrasion resistance Primarily concrete coatings, e.g. food factories, showrooms, laboratories, hospitals, nuclear power stations, breweries, etc. adhesives... 

Viscosity (dynamic) dispersions in water at the 1-2% w/v level are thin colloidal suspensions. At 3% w/v and above, dispersions are opaque. As the concentration is increased above 3% w/v, the viscosity of aqueous dispersions increases rapidly at 4-5% w/v, dispersions are thick, white colloidal sols, while at 10% w/v firm gels are formed. Dispersions are thixotropic at concentrations greater than 3% w/v. The viscosity of the suspension increases with heating or addition of electrolytes, and at higher concentrations with aging. 

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