(308g) Dynamic Binary Complexes As Super-Adjustable Viscosity Modifiers for Hydraulic Fracturing Fluids

Production of fossil fuel from unconventional reservoirs has increased in the past decade due to the advances in extraction technologies horizontal drilling and hydraulic fracturing. However, the recovery of oil and gas in place from unconventional reservoirs is currently estimated to be less than 20% by recent studies. One of the leading reasons for the low production is the inability of current hydraulic fracturing processes to stimulate the reservoir area contacted by the wellbore effectively. Here we describe a novel hydraulic fracturing fluids involving dynamic binary complexes (DBCs) to overcome some of these challenges. DBCs relies on the dynamic complexation of long-chain amino-amine with a carboxylic acid through electrostatic and hydrophobic interactions to produce multilayered, flexible, entangling nanowires with pH-sensitive viscosities. Their viscosity can be changed in a reversible-fashion through changing pH between base and acid. At the high viscosity state, such pH-responsive DMCs display high mesh rigidity and ultra-long persistence lengths. At the low viscosity state, the multilayered nanowires responsible for high viscosities and mesh rigidity can completely disassemble into molecular building blocks. This feature is especially suitable to minimize any risk to the proppant formation and permeation damage after the fracturing and fluid injection step.