Abstract: The cationic plugging agent of water base drilling fluid was prepared by emulsion polymerization with styrene (St), butyl acrylate (BA) and cationic polymerizable monomer. The structure characteristics of the plugging agent were analyzed by infrared spectrum. The result of soaking test with clay ball showed that cationic plugging agent emulsion with a mass fraction of 5.0% was equivalent in inhibiting clay hydration property of saturated brine. The effect of cationic plugging agent on the properties of CaCl2 free phase drilling fluid was evaluated. The results showed that the high temperature and high pressure filtration (120~130 ℃) could be controlled at about 10 mL for the non phase drilling fluid with CaCl2 content of 25.0% when the cationic plugging agent is 2.0%.

Key words: Tight oil and gas, Borehole stability, Drilling fluid, Cationic plugging agent

摘要： 以苯乙烯（St）、丙烯酸丁酯（BA）及阳离子可聚合单体，利用乳液聚合方法制备水基钻井液用阳离子型封堵剂，采用红外光谱分析了封堵剂的结构特点。泥球浸泡实验结果表明，质量分数为5.0%的阳离子型封堵剂乳液和饱和盐水抑制黏土水化性能相当。评价了阳离子型封堵剂对CaC12无土相钻井液性能的影响。结果表明，加入质量分数为2.0%的阳离子型封堵剂，可将CaC12质量分数为25.0%的无土相钻井液的高温高压滤失量（120～130 ℃）控制在10.0 mL左右。

关键词: 致密油气, 井壁稳定, 钻井液, 阳离子型封堵剂