新型可延迟膨胀类堵漏剂的合成与性能评价

现有的凝胶堵漏剂吸水膨胀速度过快，导致堵漏剂难以进入漏层；部分进入漏层的堵漏剂，因提前膨胀致使填塞层强度低，堵漏效果差。采用丙烯酸（AA）、丙烯酸甲酯（MA）、2-丙烯酰胺-2-甲基丙磺酸衍生物（AMPSA）、N，N’-亚甲基双丙烯酰胺（MBA）为原料合成可延迟膨胀堵漏剂BZYD-1，对其进行表征，评价了其可延迟性能及承压堵漏能力。结果表明:所合成的可延迟膨胀堵漏剂BZYD-1热稳定性好，抗温达150℃；室温时，清水浸泡几乎不发生吸水膨胀，碱性条件下浸泡4 h膨胀率不大于50%；80℃时，碱性条件下吸水膨胀率达到17.8倍，具有显著的延迟膨胀效果，承压能力为4 MPa。该延迟膨胀堵漏剂具有较好的应用前景。 

Synthesis and Evaluation of a New Swelling Deferrable Lost Circulation Material

Gel lost circulation material (LCM) presently in use swells fast when absorbing water, making it difficult for the LCM to enter into the flow channel in formation through which mud is lost. Part of the LCM entering the flow channel forms plugs of low strength in the flow channels because of early swelling, resulting in poor mud loss control. A swelling deferrable lost circulation material (LCM), BZYD-1, has been synthesized with acryl acid (AA), methyl acrylate (MA), 2-acrylamide-2-methyl propane sulfonic acid derivative (AMPSA), and N,N'-methylene-bis-acrylamide (MBA), and characterized. Laboratory evaluation showed that BZYD-1 had good thermal stability, and was resistant to high temperature to 150℃. At room temperature, BZYD-1 did not swell in fresh water, and rate of swelling after soaking for 4 hours in alkaline water was less than 50%. At 80℃, BZYD-1 soaked in alkaline water swelled to 17.8 times of its original size, demonstrating remarkable deferred swelling. The swollen BZYD-1 had pressure bearing capacity of 4 MPa. This swelling deferrable LCM has good application prospect.