具有双重交联结构的耐高温聚合物微球的制备及耐温机制研究

Because of that the properties and performance of polymer microsphere are not affected by injection water, shearing and gelatinizing environment, it is one of the most important deep profile control agents for oil reservoir. However, the temperature resistant property of current polymer microspheres cannot meet requirement of 120℃or higher. Moreover, in China there are many heterogeneous reservoirs with temperature higher than 120℃, the deep profile control agents with high temperature resistant capacity are desired urgently. Consequently, in this project, we initially use acrylamide (AM) combining with organic crosslinking agent and organo-metallic crosslinker to prepare polymer microspheres. There are both covalent bond and coordinate bond structure existing. Due to this double crosslinking structure, the temperature resistant capacity of polymer microsphere is improved significantly, thus to meet the requirement of high temperature reservoirs. The relation between temperature resistant property and microstructure of polymer microsphere with double crosslinking is studied. Based on this result, the effect of double crosslinking structure on temperature resistant is investigated and the mechanism of temperature resistant of polymeric microsphere with double crosslinking structure is investigated, consequently the theoretical guidance of polymer microsphere preparation can be provided, which is significant to enhance oil recovery of high temperature reservoirs after water flooding.

聚合物微球因其不受配注水、剪切、成胶环境等影响，已经成为重要的油田深部调剖剂。但目前使用的聚合物微球耐温性能还无法满足高温（温度>120度）油藏的深部调剖要求，而我国有很多油田属于高温非均质油藏，急需耐高温的聚合物微球深部调剖剂。为此，本项目首次提出利用丙烯酰胺（AM）同时与有机交联剂和有机金属交联剂反应，使制得的聚合物微球分子结构中同时含有共价键与配位键的双重交联结构。这种双重的交联结构赋予聚合物微球更优异的耐温性能，从而满足高温油藏的深部调剖要求。通过研究具有双重交联结构的聚合物微球的微观结构与宏观的耐温性能间关系，揭示这种双重的交联结构对聚合物微球的耐温性能的影响规律，阐明双重交联结构的聚合物微球的耐温机理，从而为耐高温聚合物微球的制备提供理论指导。这对于提高我国高温油田水驱后期原油采收率具有重要意义。

聚合物微球由于其独特的粒径可控性、较好的溶胀性、耐盐性、优良的弹性和可注入性等特点已经成为了油田深部调剖技术中的一种重要调驱剂。但是由于聚合物微球本身耐温性差的缺点，因此无法满足高温（>120℃）油藏的深部调剖要求。而我国有很多油田属于高温非均质油藏，急需耐高温的聚合物微球深部调剖剂。为此，本课题首次提出利用丙烯酰胺（AM）同时与有机交联剂和有机金属交联剂反应，使制得的聚合物微球分子结构中同时含有共价键与配位键的双重交联结构。这种双重的交联结构赋予聚合物微球更优异的耐温性能，从而满足高温油藏的深部调剖要求。本课题通过在主单体AM中添加耐温单体N-乙烯基吡咯烷酮（NVP）和2-丙烯酰胺-2-甲基丙磺酸（AMPS），同时采用有机交联剂和金属交联剂，首次构建并制备了具有双重交联结构（DCS）的纳微米耐温聚合物微球，该聚合物微球同时具有共价交联结构和配位交联结构使其在150℃高温环境可以稳定存在200 d以上。本课题还对DCS聚合物微球的粒径分布、表面形貌、元素分布及微观结构进行了表征，以及对DCS耐温微球的耐温性能、溶胀性能、耐盐性能、抗剪切性能、封堵运移特性和提高采收率效果进行了研究，所制备的聚合物微球除了具有优异的耐高温性能外，同时具有良好的溶胀、封堵运移特性，提高采收率效果显著。同时研究了具有DCS聚合物微球的微观结构与宏观的耐温性能间关系，探究了DCS耐温聚合物微球的耐温机理。明确了聚合物微球的交联结构与耐温性能及溶胀性能之间的相互关系。确定了同时满足耐温性与溶胀性的聚合物微球交联结构。阐明了DCS聚合物微球的耐温机理，提出“二次交联”机理来解释具有双重交联结构聚合物微球耐温的根本原因，从而为耐高温聚合物微球的制备提供了理论指导。这对于提高我国高温高盐油田水驱后期原油采收率具有重要意义。