一种pH响应性酸化用自增稠聚合物

Research on a self-thickening and pH-responsive acidification polymer

以丙烯酰胺(AM)、N-(3-二甲氨丙基)甲基丙烯酰胺(DMAPMA)与十八烷基二甲基烯丙基氯化铵(DMAAC-18)为原料合成了一种具有pH响应的聚合物自增稠剂(ADD)。优化了ADD的合成条件,利用FTIR分析了ADD的结构,同时对ADD性能进行了评价。实验结果表明,ADD的最优合成条件为:n(AM)∶n(DMAPMA)∶n(DMAAC-18)=94∶5∶1、总单体用量25%(w)、引发剂加量0.5%(w)(基于单体总质量)、50℃、6 h,该条件下制得的ADD溶液最大黏度为532 mPa·s。当ADD含量为1.2%(w)、盐酸含量为5%(w)时,ADD酸液黏度最大,在25℃、170 s^-1剪切下黏度为427 mPa·s。在140℃、170 s^-1下剪切60 min后,ADD残酸液黏度仍可保持100 mPa·s以上,ADD残酸具有良好的黏弹性与抗剪切能力,能够实现地层中酸液转向的目的。

A self-thickening and pH-response polymer(ADD)was synthesized with acrylamide(AM),N-(3-dimethylaminopropyl)methacrylamide(DMAPMA)and octadecyldimethylallyl ammonium chloride(DMAAC-18)as materials.The reaction conditions were optimized,the structure of ADD was characterized by FTIR,and the properties of ADD were studied.The result shows that the optimum conditions are n(AM)∶n(DMAPMA)∶n(DMAAC-18)94∶5∶1,total monomer amount 25%(w),initiator dosage 0.5%(w)(based on the mass of total monomer),50℃,6 h.Under the optimum conditions,the max viscosity of the ADD solution is 532 mPa·s.When ADD content is 1.2%(w),HCl content is 5%(w),the viscosity of the ADD acid reaches its peak value and is 427 mPa·s after sheared at 25℃,170 s^-1.After the residual acid solution of the ADD polymer was sheared under 140℃and 170 s^-1 for 60 min,the viscosity can still maintain 100 mPa·s or more.The ADD acid solution has good viscoelasticity which can achieve the purpose of acidification turning.