Preparation and performance of AMPS/AA/DMAA/SA copolymer as a filtrate reducer for oil well cementing

A new water-soluble polymer was prepared and evaluated as a filtrate reducer for oil well cementing. The filtrate reducer (WSP) was synthesized from 2-acrylamido-2-methylpropane sulfonic acid (AMPS), acrylic acid (AA), dimethyl acrylamide (DMAA), and sodium allylsulfonate (SA) by aqueous free radical polymerization. The synthesis conditions were optimized by orthogonal experiment. The molecule structure of the synthesized copolymer (WSP) was verified by Fourier transformer infrared spectrum (FTIR) and nuclear magnetic resonance hydrogen spectroscopy (H-1-NMR). The molecule weight of the synthesized copolymer was determined by gel permeation chromatography (GPC). The thermal stability of the synthesized copolymer was tested by thermogravimetry and differential thermogravimetry (TG and DTG). When the dosage of WSP is up to 3% in fresh water cement slurry, the FLAPI can be controlled within 58 mL. In 37% salt water cement slurry, the FLAPI can be controlled within 90 mL when the dosage of WSP is 5%. The thermal degradation of WSP is not obvious before 289 degrees C. Compared with a commercial filtrate reducer BS-100L and a reported copolymer HTF200C, the WSP has better performance. (C) 2016 Wiley Periodicals, Inc.