Abstract:

The present paper dealt with the synthesis of the AMPS/AM/AA terpolymer as a temperature-resistance, salt-tolerance fluid-loss additive, which used 2-acrylamido-2-methylpropanesulphonic acid(AMPS), acrylamide(AM) and acrylic acid(AA) monomers and initiated by a new type of the azoic initiator, V50. Optimal conditions of the synthesis determined through orthogonal experiments were proposed as a 45∶45∶10 mole ratio for AMPS, AM and AA, respectively, 60℃ for polymerization temperature, 9% for the weight fraction of monomers, 0.60% for the initiator dosage, pH 8 for the medium and 4 hours for polymerization time. The structure of the terpolymer was confirmed by infrared spectrum(IR) analysis. Differential scanning calorimetry(DSC) and thermogravimetry(TG) tests showed that a good thermo-stabilization of the terpolymer could be maintained at 300℃. The performance tests of cement slurry demonstrated that this terpolymer fluid-loss additive could control the API fluid-loss amount below 100 mL under the condition of 180℃/6.9 MPa saturated brine.

Key words: AMPS/AM/AA terpolymer, temperature-resistance, salt-tolerance, fluid-loss additive, conversion rate

摘要：

以2-丙烯酰胺基-2-甲基丙磺酸(AMPS)、丙烯酰胺(AM)、丙烯酸(AA)为单体，采用新型偶氮类引发剂(V50)合成了AMPS/AM/AA三元抗高温耐盐油井水泥降失水剂，通过设计正交实验，确定了共聚物的最佳合成条件为：AMPS/AM/AA的摩尔比为45∶45∶10，聚合反应温度为60℃，单体质量百分数为9%，引发剂摩尔百分比为0.60%，反应介质pH值为8；反应时间4 h。通过红外光谱分析验证了三元共聚物的结构；采用DSC与TG证实了三元共聚物在300℃具有较好的热稳定性；水泥浆性能测试表明,该降失水剂能够在180℃/6.9 MPa、饱和盐水中,控制水泥浆API失水量小于100 mL。

关键词: AMPS/AM/AA三元共聚物, 抗高温, 耐盐, 降失水剂, 转化率