This study was conducted to develop a new type of sealing material: double‐doped polymer‐modified cement‐based sealant (DPCS) and to verify its sealing performance. The aim is to improve the sealing effect of borehole, improve the gas extraction efficiency, and reduce methane emissions. Two kinds of polymers are doped in DPCS, namely the water‐soluble polymer emulsion (A1) and the cationic polymer (A2). The fluidity, expansion, compactness, and mechanical properties of DPCS and the single‐doped polymer‐modified sealant were tested and compared. Additionally, the effects of the polymer–cement ratio and the dispersant dosage on the sealing performance of DPCS were analyzed. To evaluate these competing effects of multiple factors on sealing performance of DPCS comprehensively, an orthogonal test was designed with range and variance analyses. The results show that with a polymer–cement ratio of 6%, 0.10% expansion agent dosage, and 1.2% dispersant dosage, the DPCS performs best on mechanical and expansion properties. A field site test at the working face 15201 of the Baiyangling coal mine was conducted to verify DPCS's sealing performance. The test results indicate that the novel DPCS can improve the concentration of extracted gas, and is also a better choice than the common sealing materials used in the mine economically. © 2020 Society of Chemical Industry and John Wiley & Sons, Ltd.

中文翻译：

---

一种新型的双掺杂聚合物改性水泥基密封胶，可增强钻孔密封性并减少甲烷排放

进行这项研究是为了开发一种新型的密封材料：双掺杂聚合物改性水泥基密封胶（DPCS）并验证其密封性能。目的是提高井眼的密封效果，提高瓦斯抽采效率，减少甲烷排放。DPCS中掺杂了两种聚合物，即水溶性聚合物乳液（A1）和阳离子聚合物（A2）。测试并比较了DPCS和单掺杂聚合物改性密封胶的流动性，膨胀性，致密性和机械性能。此外，还分析了聚合物与水泥的比例和分散剂的用量对DPCS密封性能的影响。为了全面评估多种因素对DPCS密封性能的竞争影响，设计了具有范围和方差分析的正交试验。结果表明，在聚合物与水泥的比例为6％，膨胀剂用量为0.10％，分散剂用量为1.2％的情况下，DPCS在机械和膨胀性能方面表现最佳。在白洋岭煤矿工作面15201进行了现场测试，以验证DPCS的密封性能。测试结果表明，新型DPCS可以提高抽采瓦斯的浓度，并且比经济上用于矿井的普通密封材料更好。©2020年化学工业协会和John Wiley＆Sons，Ltd. 测试结果表明，新型DPCS可以提高抽采瓦斯的浓度，并且比经济上用于矿井的普通密封材料更好。©2020年化学工业协会和John Wiley＆Sons，Ltd. 测试结果表明，新型DPCS可以提高抽采瓦斯的浓度，并且比经济上用于矿井的普通密封材料更好。©2020年化学工业协会和John Wiley＆Sons，Ltd.