聚合物基纳米SiO_2复合微球固井降失水剂的合成及表征  

Synthesis and Characterization of Composite Polymer Microspheres Based Nano–Silica for Cementing Fluid Loss Additive

作　　者：张健[1] 彭志刚[1] 邹长军[1] 陈大钧[1] 张博建 焦利宾[1] 

机构地区：[1]西南石油大学化学化工学院,成都610500

出　　处：《硅酸盐学报》2017年第11期1649-1657,共9页Journal of The Chinese Ceramic Society

基　　金：国家863项目"海上大位移井固井关键技术研究"(2012AA09 1501-003)资助

摘　　要：针对目前水溶性高分子类固井降失水剂抗温抗盐能力差、综合性能欠佳等问题,采用无皂乳液自由基聚合法,以苯乙烯(St)、丙烯酸丁酯(BA)、甲基丙烯酸甲酯(MMA)为单体,对苯乙烯磺酸钠(SSS)、2–丙烯酰胺基–2–甲基丙磺酸(AMPS)为离子型共聚乳化剂,纳米二氧化硅为填料,制备P(St/BA/MMA)–g–Si O2复合微球降失水剂(ZJD–220),考察了AMPS/SSS对聚合速率及复合微球性能的影响,评价了含降失水剂(ZJD–220)水泥浆的降失水、抗温抗盐等工程性能,探讨了其在水泥浆中的降失水作用机理。结果表明:复合聚合微球粒径分布均匀且窄,具有典型核壳结构和良好的耐热性能;复合微球(ZJD–220)可以明显改善水泥浆的降失水、耐温耐盐性能,在温度为200℃,复合微球的质量分数为3.0%时,淡水基水泥浆失水量为43 m L,盐水基水泥浆(18%Na Cl)失水量为28 m L;与不同水泥浆体系及外加剂具有良好的配伍性。通过化学分析、电镜扫描等手段揭示降失水剂ZJD–220的降失水作用机理为:聚合物微球在水泥颗粒及滤饼孔隙间通过"吸附架桥–填充堵塞–聚集成膜"的协同作用,改善了水泥浆滤饼质量,降低了滤饼渗透率,控制了水泥浆失水量。P（St/BA/MMA）-g-SiO2 composite microspheres （ZJD-220） were prepared via a soap-free emulsion polymerization method with syrene （St）, butyl acrylate （BA）, methyl methacrylate（MMA） as monomers, sodium p-styrenesulfonate （SSS） and 2-acrylamido-2-methyl propane sulfonic acid （AMPS） as ionic copolymer emulsifiers, and nano-silica as a filler. The effect of AMPS/SSS on the polymerization rate and properties of the composite microspheres was investigated. The engineering performance of fluid loss, temperature resistance and salt tolerance of cement slurry with ZJD-220 were evaluated, and the filtration reduction mechanism of ZJD-220 in cement slurry was further discussed. The results indicate that the particle size distribution of the composite polymer materials with a typical core-shell structure and good temperature resistance. The fluid loss, temperature resistance and salt tolerance of cement slurry are significantly improved by ZJD-220 when the temperature is 200~C and the mass fraction of ZJD-220 is 3%, and the fluid loss of the fresh water and salt based cement slurry （18%NaC1） is 43 mL and 28 mL respectively. Based on the results by chemical analysis and transmission electron microscopy, the mechanism of fluid loss reduction of ZJD-220 was revealed. Polymer microspheres （ZJD-220） in cement particles and filter cake pore can improve the quality and the permeability of filter cake and the fluid loss amount of cement slurry through the synergistic reaction of ＇bridging adsorption-filled and blocked-gathered film＇.

关 键 词：固井 降失水剂 纳米二氧化硅 抗温抗盐 复合聚合物微球 

分 类 号：TQ317[化学工程—高聚物工业] TQ172