摘要
将工业品蒙脱土提纯,与铵盐进行离子交换,在PHP(HPAM)水溶液中冷冻干燥,得到蒙脱土的固态化纳米前驱物NPP,再用某种齐聚物包裹,得到核 壳结构颗粒(最大粒径0.5～2μm),在单体聚合时颗粒剥离或分散,蒙脱土的粒径降至20～70nm,团聚颗粒占3%～5%,成为纳米复合材料(纳米颗粒)。介绍了2种纳米化前驱物的特性。超细颗粒与聚合物之间的强相互作用使纳米复合材料中聚合物的热降解性减小。用钻井液常规测定方法考察了所制备的纳米颗粒(主要是NPP PHP纳米颗粒)悬浮液的流变及其他特性:增粘性远大于蒙脱土+PHP混合物浆;AV,PV,YP值对聚合物浓度很敏感;n、k值变化相对较小;在150℃热处理后粘度、滤失量、密度变化小;滤饼致密光滑;随聚合物浓度增大,pH迅速降至一恒定值(符合Kubo等的超微颗粒电中性理论);AV值随NaCl加量增大而增大,随CaCl2加量增大而减小。在NPP PHP泥饼中检出ZnS,CaS,CaCO3等物质,应为超细蒙脱土的生成物,生成反应有利于去除H2S和CO2,其不利影响有待研究。图5表2参12。
Through purification, ion exchange with an ammonium salt, freeze vacuum drying in aqueous PHP solution of montmorillonites (MMTs), solidified nanoparticle precursors NPPs are obtained. The NPPs are treated with an oligamer to form coreinshell particles with size no more than 0.5—2.0 μm and the latters are mixed with polymerizable monomer and in polymerization process exfoliate or disperse with MMTs size diminished to 20—70 nm and agglomeration rate of 3—5%. Thus nanocomposites (nanosized particles) are prepared. The characteristics of 2 NPPs are presented. The rheologic and other behavior of nanoparticles, mainly NPPPHP, in aqueous suspension is investigated by standard methods of testing drilling fluids and following results are obtained: the viscosifying capacity is notably higher than that of MMTs/PHP mixture; the values of AV,PV and YP are sensitive to organic phase concentration while changes in n and k values are relatively even; changes in viscosities, filtrate loss, and density after ageing at 150℃ are small; the cake formed is compact and smooth; the pH value decreases quickly to a constant with increase in organic phase concentration—a phenomenon in accordance with Kubos concept of electric neutrality for ultrafine particles; the AV value increases with increasing NaCl concentration and decreases with increasing CaCl2 concentration. In NPPPHP cakes ZnS, CaS, CaCO3, etc are detected and might originate from ultrafine MMTs particles, the reactions leading to their formation are favorite to removal of H2S and CO2 and the negative effects are a subject of further study.
出处
《油田化学》
CAS
CSCD
北大核心
2003年第2期99-102,共4页
Oilfield Chemistry
基金
中国石油天然气集团公司创新基金项目(编号J0206)
重质油加工国家重点实验室资助项目(编号J0220)。
关键词
蒙脱土-聚合物纳米复合材料
油田开发
水基钻井液
流变性
耐热性
montmorillonites
solid precursors
polymers
nanocomposites
water base drilling fluid
rheologic behavior
heat resistance
