Gelling agent phosphates

Anionic Association Polymer. Another type of lost circulation agent is a combination of an organic phosphate ester and an aluminum compound, for example, aluminum isopropoxide. The action of this system as a fluid loss agent seems to be that the alkyl phosphate ester becomes crosslinked by the aluminum compound to form an anionic association polymer, which serves as the gelling agent [1488]. 

D. A. Huddleston. Liquid aluminum phosphate salt gelling agent. Patent US 5110485,1992. 

C. K. Jones, D. A. Williams, and C. C. Blair. Gelling agents comprising aluminium phosphate compounds. Patent GB 2326882, 1999. 

In 1970, Monroe and Rooker(28) claimed the use of aluminum salts of acid orthophosphate esters as viscosity builders for use in fracturing fluids. The application of these materials began a new era of hydrocarbon gelling agents. Monroe(29) later claimed the use of Fe30it as a metal activator of phosphate esters and in 1971 described several other metals(30) that could be used with amine neutralization agents. Numerous metallic ionic derivatives can be used as effective "activators" or crosslinkers to prepare a gel. 

Large volumes of soap are used in industrial applications as gelling agents lor kerosene, paint driers, and as surfactants in emulsion polymerization. See also Soaps. Concern over water eutrophication resulted in a ban of phosphorus in laundry detergents. Phosphates have been effectively replaced by combinations of zeolite, citrate, and polymers, coupled with rebalanced synthetic active systems. Soap itself is generally present only as a minor component of surfactants. 

The build-up of Ca(0H>2 or Mg(OH)2 at the anolyte interface of the membrane-brine system can be prevented by addition of certain sequestering-gelling agents into the brine such as phosphoric acid or phosphate salts (43). A strongly hydrogen bonded non-stoichiometric calcium orthophosphate gel is formed at pH s greater than 5 to sequester the divalent ions at the membrane-brine interface, but the gel dissolves at pHs of 2-3.5. 

Chemg A, Takagi S, Chow LC. Effects of hydroxypropyl methylcellulose and other gelling agents on the handling properties of calcium phosphate cement. J Biomed Mater Res. 1997 Jun 5 35(3) 273-7. 

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