Water-dispersible compositions

An additional opportunity that arises from applying polymer-based materials is the preparation of water-dispersible composites, which is an essential feature for biomedical purposes, as it is possible to attach bio-active molecules to the poly-mer/CNTs systems and specifically deliver them to cells. In this manner, plasmid DNA, siRNA (Fig. 3.11) and several anticancer agents have been successfully bound and delivered [61]. The stratagem to generate materials with good solubility in aqueous media usually involves the presence of water-soluble polar groups (e.g. phosphates, protonated amines etc.) embedded in the polymer chain. 

R. J. Lo, J. L. Chen, and H. B. Scher, Dry Water-Dispersible Compositions of Mieroencap-sulated Pesticides, United States Patent 6,358,520,2002. 

Recent patents describe the use of solvents to improve the properties of agricultural chemicals. In one invention, a carrier was developed from an agglomerated composition of plant fibers and mineral filler. The purpose of the carrier is to absorb and hold a large quantity of pesticide until it is delivered to the application site. The pesticide must be in a form of low melting liquid. In order to reduce its melting point, solvents selected from aromatic hydrocarbons are used to dissolve pesticide. In a water dispersible composition of insecticide, solvent is used to convert insecticide to a liquid form at room temperature. Solvents proposed for this application are from a group of aUcyl aromatic hydrocarbons, methyl esters of alkanoic acids, and ester mixtures derived from plant oils. 

By depolymerizing PET waste with a polyol and subsequently condensing the oligomeric product with a polycarboxylic acid or anhydride, polyester resins are produced which have wide industrial applications. Depending on the polyol and polycarboxylic acid or anhydride used, saturated resins, alkyd resins, or unsaturated resins are obtained. PET wastes have been used for the production of alkyd resins in water thinnable paints. The materials obtained from the reaction of PET with a mixture of fatty acids high in linoleic acid content and trimethylolethane have been used in the preparation of water-dispersible coatings. Products of the depolymerization of PET with trimethylolpropane and pentaerythritol are used in the manufacture of high-solids paints. In the first step, PET is depolymerized with trimethylopropane and pentaerythritol at temperatures of 230-240°C. The final paint compositions contain 30-50% of PET depolymerization products.12... 

A mixture of monolauryl phosphate sodium salt and triethylamine in H20 was treated with glycidol at 80°C for 8 h to give 98% lauryl 2,3-dihydro-xypropyl phosphate sodium salt [304]. Dyeing aids for polyester fibers exist of triethanolamine salts of ethoxylated phenol-styrene adduct phosphate esters [294], Fatty ethanolamide phosphate surfactant are obtained from the reaction of fatty alcohols and fatty ethanolamides with phosphorus pentoxide and neutralization of the product [295]. A double bond in the alkyl group of phosphoric acid esters alter the properties of the molecule. Diethylethanolamine salt of oleyl phosphate is effectively used as a dispersant for antimony oxide in a mixture of xylene-type solvent and water. The composition is useful as an additive for preventing functional deterioration of fluid catalytic cracking catalysts for heavy petroleum fractions. When it was allowed to stand at room temperature for 1 month it shows almost no precipitation [241]. 

Carotenoid/ curcumin/porphyrin Water dispersion without using compositions surface-active substance... 

Colorant containing annatto and Ca caseinate as carrier mixed with water to be added directly to cheese milk yielding uniform colored cheese mass Water-dispersible beadlet of p-carotene is mixed with oil to attein composition that remains stable even in presence of polyphosphates and with antioxidant action even in absence of ascorbic acid Blending carotenoid pigment and soybean fiber (wifii tomato juice) as effective ingredient for dispersion stability... 

Dispersant compositions for the treatment of oil spills at the surface of the water consist of a mixture of water, a hydrocarbon solvent, and a mixture of surfactants consisting of 55% to 65% by weight of emulsifiers and 35% to 45% by weight of dioctyl sodium sulfosuccinate. The emulsifying agents consist of a mixture of various sorbitan oleates [351-354]. 

A. Charlier. Dispersant compositions for treating oil slicks on the surface of water (compositions dispersantes pour le traitement de nappes d huile a la surface de I eau). Patent EP 254704, 1988. 

A. Charlier. Dispersant compositions for treating oil slicks on cold water. Patent EP 398860, 1990. 

J. G. Doolan and C. A. Cody. Pourable water dispersible thickening composition for aqueous systems and a method of thickening said aqueous systems. Patent US 5425806, 1995. 

Y. Inoue, Photocatalytic activity of the Ru02-dispersed composite p-block metal oxide LiInGe04 with d10-d10 configuration for water decomposition,... 

Dye-doped polymeric beads are commonly employed in different formats (Fig. 5), namely as water-dispersible nanosensors, labels and in composite materials (DLR-referenced and multianalyte sensors, sensor arrays, magnetic materials, etc.). The sensing properties of the dye-doped beads are of little or no relevance in some more specific materials, e.g., the beads intended for photodynamic therapy (PDT). The different formats and applications of the beads will be discussed in more detail in the following section, and the relative examples of sensing materials will be given. 

The dynamics of oil-in-water dispersion (OWD) are complex and have relevance related to potential toxicity or hazard. In comparing the toxicides to marine animals of oil-in-water dispersions prepared from different oils, not only the amount of oil added but also the concentrations of oil in the aqueous phase and the composition and dispersion-forming characteristics of the parent oil must be taken into consideration. In comparing the potential impacts of spills of different oils on the marine biotic community, the amount of oil per unit water volume required to cause mortality is of greater importance than any other aspect of the crude oil behavior. 

An example of the kinds of data required for land disposal options would be Information on soll/pestlclde Interactions to determine the effect of the pesticide on the soil and soil on the pesticide. The physical composition of the soil and the physical properties of the pesticide and Its formulation will determine the adsorption, leaching, water dispersal, and volatilization of the pesticide which. In turn, determine the mobility of the pesticide In soil. Even pesticides of closely related structures may have very different soil retention properties. Much of this data will be available from that developed to meet other registration data requirements with the exception that disposal rates are often orders of magnitude higher than normal application rates and the difference must be considered. 

Water-dispersible polyisocyanate compositions containing polyethylene oxide were previously prepared by the authors (2) and used as aqueous resin adhesives. 

Comparson of the transitions observed by differential scanning calorimetry in membranes of M. laidlawii and in water dispersions of the lipids from the membranes support the concept that most of the lipids exist as a smectic mesophase in the membranes. The evidence for a bilayer structure is straightforward in this case. Lipid transition temperatures are a function of fatty acid composition and correlate well with biological properties. The calorimeter possesses advantages over high resolution NMR for M. laidlawii, and perhaps in many other systems, because the data can be interpreted less ambiguously. In M. laidlawii membranes the bilayer appears to be compatible with the same physical properties observed in other membranes—a red-shifted ORD, lack of ft structure in the infrared, reversible dissociation by detergents, and poorly... 

In an attempt to overcome the low infusible character and low solubility of aniline, dispersion polymerization of aniline was conducted in water-dispersible colloidal particles that can be cast as films or blended with other materials to prepare composites. HRP mediated polymerization of aniline in a mixture of phosphate buffer and organic solvent resulted in polyaniline composed of ortho-directed units and para-directed units. Increasing the pH or adopting an organic solvent with a high dielectric constant, enhanced the production of ortho-directed units [54]. These ortho-directed polyanilines were more thermally flexible and electrically conductive. 

It is well known that water dispersions of amphiphile molecules may undergo different phase transitions when the temperature or composition are varied [e.g. 430,431]. These phase transitions have been studied systematically for some of the systems [e.g. 432,433]. Occurrence of phase transitions in monolayers of amphiphile molecules at the air/water interface [434] and in bilayer lipid membranes [435] has also been reported. The chainmelting phase transition [430,431,434,436] found both for water dispersions and insoluble monolayers of amphiphile molecules is of special interest for biology and medicine. It was shown that foam bilayers (NBF) consist of two mutually adsorbed densely packed monolayers of amphiphile molecules which are in contact with a gas phase. Balmbra et. al. [437J and Sidorova et. al. [438] were among the first to notice the structural correspondence between foam bilayers and lamellar mesomorphic phases. In this respect it is of interest to establsih the thermal transition in amphiphile bilayers. Exerowa et. al. [384] have been the first to report such transitions in foam bilayers from phospholipids and studied them in various aspects [386,387,439-442]. This was made possible by combining the microscopic foam film with the hole-nucleation theory of stability of bilayer of Kashchiev-Exerowa [300,402,403]. Thus, the most suitable dependence for phase transitions in bilayers were established. 

This study investigated the potential of ex situ water-dispersible colloids with diverse mineralogical composition to desorb Pb from the contaminated soil matrix of undisturbed soil monoliths and co-transport it to groundwater. The study employed intact monoliths contaminated by Pb, which were flushed with colloid suspensions of different mineralogical composition and D-H20, used as a control. The soil monoliths represented upper solum horizons of the soils used in Case Study 1 (Maury and Loradale). The soil colloids were fractionated from low ionic strength Bt horizons of Alfisols with montmorillonitic, mixed, and illitic mineralogy. 

Water-dispersible lecithins are made by chemical modification, or by mixing ordinary lecithin with nonionic surfactants. Many of the products recommended in the literature and technical brochures for water-based compositions include such chemically modified, water-dispersible, lecithin compounds (e.g., hydroxy-lated, acylated, fractionated, and refined grades) (428, 431 33). Usually 0.5% to 1% modified lecithin is recommended in polyvinyl acetate-based paints, acrylic emulsions, and in butadiene—styrene emulsion paints. 

Alderman DA, Schulz GJ. Method of making a granular, cold water dispersible coating composition for tablets. United States Patent No. 4,816,298 1989. 

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