含高比例疏水单体的降阻剂的合成及性能评价

使用3-溴丙烯和N,N-二甲基十八烷基叔胺合成水溶性阳离子疏水单体N,N-二甲基十八烷基烯丙基溴化铵(DOAB),仅使用水作为溶剂,合成了含有高摩尔分数疏水单体的部分水解聚丙烯酰胺型降阻剂,以核磁氢谱和元素分析得到降阻剂的结构为P(AM0.877-AA0.113-DOAB0.01);激光光散射法测得降阻剂摩尔质量为1.22×10~7 g/mol;黏度法测得临界缔合浓度(CAC)为2.8 g/L。测试了不同质量浓度下降阻剂稀溶液(即滑溜水)在不同流速下的摩阻,以清水为空白组计算降阻率,当降阻剂质量浓度为1.3 g/L时,降阻率最高可达72%;在盐水中,滑溜水降阻率下降,通过提高降阻剂质量浓度的方式可以提升降阻率,盐水中的降阻剂质量浓度为2 g/L时,降阻率最高达70.06%。由SEM得知,降阻剂在水中形成的网状结构是聚合物具有降阻性的直接原因。

Synthesis and Performance Evaluation of a Drag Reducer Agent Containing High Proportion of Hydrophobic Monomer

A water-soluble cationic hydrophobic monomer, N, N-dimethyl octadecyl allyl ammonium bromide, was synthesized by using 3-bromopropene and N,N-dimethyloctadecylamine in acetone. Using water as solvent, a partially hydrolyzed polyacrylamide containing high proportion of hydrophobic monomer was synthesized and aimed to be used as drag reducer agent (DRA). NMR spectrum confirmed that structure of the product was consistent with the preset and hydrophobic monomer accounted for 1%, molecular weight of the drag reducer was 1.22×107 g/mol which characterized by laser light scattering. The critical association concentration measured by the viscosity method is 0.28%. Friction of diluent solution at different flow rates in the pipeline was tested, and drag reductions (DR) were calculated by using the clear water as blank group. When the concentration of DRA is 0.13%, DR can reach up to 72%. In salt water, DR decreases. By increasing concentration of DRA, DR can be increased. When the amount is 0.2%, DR is up to 70.06%. It is known from SEM that network structure formed by DRA in water is the direct cause of the resistance reduction of DRA.