Synthesis and Study of Cement Retarder for Large Temperature Difference

The development of unconventional oil and gas fields presents significant challenges for traditional retarders due to the large temperature variations in deep wells and long sealing sections. This study synthesized a retarder using 2-acrylamide-2-methylpropanesulfonic acid (AMPS), itaconic acid (IA), and acrylamide monomers, which offers excellent thermal stability and low-temperature cement strength development. Experimental results show that the retarder has an initial thermal decomposition temperature of 281.3℃, indicating high thermal stability. Under thickening conditions at temperatures up to 160℃, the retarder demonstrated effective time-regulating properties, allowing for precise control of cement slurry thickening time. Additionally, the cement slurry prepared with this retarder meets requirements for water loss, free water, and sedimentation stability, ensuring stability in complex environments. At 60℃, the slurry developed a compressive strength of over 10 MPa, ensuring reliable cementing performance. This study presents a new solution for deep and ultra-deep well cementing operations, capable of addressing high temperatures and significant temperature variations.