School of Chemistry and Chemical Engineering in Chongqing University of Science Technology
提出基于可逆加成-断裂链转移(RAFT)水溶液聚合制备调驱用微纳米级聚丙烯酰胺凝胶分散体，以期解决传统调驱剂制备工艺复杂及需要添加有机溶剂的问题。首先合成了一种新型水溶性RAFT剂，再用该链转移剂在纯水中一步制备出调驱用聚丙烯酰胺凝胶分散体。探究了反应物配比、聚合温度、聚合时间及固含量对其性质的影响，测试了凝胶分散体的流变性和粘弹性特征。表征了凝胶分散体的温度响应性、盐度响应性及pH响应性。结果表明，凝胶分散体的粘度随温度升高而降低、随pH值升高而降低，但影响程度较小，而其粘度几乎不受矿化度影响。最后用原子力显微镜(AFM)、扫描电镜(SEM)以及纳米粒度分析仪表征了其微观形貌及粒径。结果表明，凝胶分散体为不规则球状结构，且凝胶分散体的微米粒径在0.92 ~ 6.13 μm，纳米粒径为48 ~ 76 nm之间，证实了凝胶分散体的分子尺度为微纳米级别。
Based on reversible addition fragmentation chain transfer (RAFT) aqueous polymerization, the micro/nano-polyacrylamide gel dispersions for profile-controlling and flooding were prepared to solve the problems of complicated preparation processes of common profile-controlling and flooding agents and the need to add organic solvents. A new water-soluble RAFT agent was synthesized, and then polyacrylamide gel dispersions were prepared by using the RAFT agent in water. The effects of reactant ratio, polymerization temperature, polymerization time and solid content on its properties were investigated. The rheological and viscoelastic properties of gel dispersions were tested. The temperature response, salinity responsiveness and pH responsiveness of gel dispersions were characterized. The results showed that the viscosity of gel dispersions decreased with the increase of temperature and decreased with the increase of pH value, but had little effect, and their viscosity was almost not affected by mineralization. Finally, the microstructure and particle size were characterized by atomic force microscope (AFM), scanning electron microscope (SEM) and nano particle analyzer. The results showed that the gel dispersion was irregular globular structure. The micron diameter of the gel dispersions was 0.92 ~ 6.13 μm and the diameter of the nanoparticles was 48 ~ 76 nm, which confirmed that the molecular scale of gel dispersions prepared by RAFT aqueous polymerization was micro/nano scale.