关键词: 缓凝剂, 抗高温, 复配, 低密度水泥体系, 温敏性

Abstract: With the oil exploration tending to approach hydrocarbon reservoir, both the length of cementing and the bottom temperature increase accordingly. The temperature resistance of a high temperature retarder needs to be improved. This research synthesized a polymer from AMPS and IA(Itaconate). The synthesis process was optimized by single factor method. With 1% initiator at mixing 6h under 60℃, when the monomer ratio of n(AMPS):n(IA) was 50:20, the conversion rate and initial setting time was the highest. High temperature retarder LY was made by mixing with the polymer and hydroxy carboxylate. The application of this temperature retarder LY in low-density cement showed that this LY retarder had a low temperature sensitivity, confirmed by initial setting time. The dispersion and stability of LY was confirmed by LY's improvement on the rheology of cement slurry. The thickening curve at high temperatures demonstrated that LY can be temperature resistant at as high as at 125℃, satisfying the cementing requirements. The effects of the retarder on cement were analyzed by XRD, providing more data in the investigation of retarding mechanism.

Key words: retarder, high temperature resistance, complex, low-density cement, temperature sensitivity