Development and evaluation of a high temperature and high salinity resistant rheological enhancer for water-based drilling fluids

Abstract

A rheology enhancer MMA for water-based drilling fluids was developed using acrylamide (AM), sodium p-styrenesulfonate (SSS), maleic anhydride (MA) and lauryl methacrylate (LMA). MMA has hydrophobic side chains that can form hydrophobic association structures in the drilling fluid, thus giving the drilling fluid the properties of NaCl-promoted viscosity enhancement. When the drilling fluid with 2% MAA was hot-rolling at 200°C and 30% NaCl for 16h, its apparent viscosity and yield point were 29.0 mPa·s and 12.0 Pa, respectively. Meanwhile, its rheological enhancement and viscosity retention properties were better than those of common oilfield products such as CMC, PAC and Driscal D at the same addition.