Patent ID: 8505631
Filing Date: 2013-08-13
Classification: A61K,A61Q,C07C,C08F,C09K

Abstract:
1. A method for fracturing a geologic formation, comprising directing a stream of an aqueous composition at a surface of the formation at a pressure and flow rate at least sufficient to initiate, extend, or initiate and extend one or more fractures in the formation, the aqueous composition, comprising: (I) water (II) a pH responsive polymer comprising, based on the total weight of monomeric units, (a) from about 25 to about 70 percent by weight acid monomeric units, each independently comprising a carboxylic acid-functional substituent group, (b) from about 30 to about 70 percent by weight nonionic monomeric units, each independently comprising a nonionic substituent group, and (c) from about 0.05 to about 20 percent by weight hydrophobic monomeric units, each independently comprising a functional group according to structure (I): wherein:  or —O—CH(R (III) at least one of: (a) one or more surfactants selected from anionic surfactant, cationic surfactants, nonionic surfactants, amphoteric surfactants, zwitterionic surfactants, and mixtures thereof, and (b) particles dispersed in the composition.