耐温耐盐疏水缔合聚合物的合成及性能评价

Synthesis and performance evaluation of temperature-resistant, salt-resistant hydrophobic associative polymers

摘要:

以丙烯酰胺(AM)、疏水单体烯丙基十二胺和耐盐单体H-66为原料,通过自由基水溶液聚合制备一种聚丙烯酰胺类聚合物RDTA。通过1H NMR和FTIR表征聚合物结构,通过表观黏度、SEM和流变性能测试研究了RDTA在不同溶液中的缔合效应和该缔合行为随温度变化的影响关系。实验结果表明,RDTA的临界缔合质量分数(W*)在0.25% ~ 0.3%。盐离子对RDTA高分子链的刺激作用能够增强该分子链的结构黏度。弹性模量G′随RDTA质量分数的增加而增大,溶液体系表现出弹性体,体系的空间结构更加密集。70℃、90℃和120℃,170 s-1剪切下,0.5% RDTA在6% NaCl盐溶液中剪切时间 < 300 s时,溶液黏度呈现缓慢上升趋势,说明RDTA在NaCl盐溶液中存在盐刺激RDTA溶液增稠的现象,继续剪切1 h后,剪切剩余黏度仍60 mPa·s以上。

Abstract:

A kind of polyacrylamide polymer RDTA was prepared by free radical aqueous solution polymerization with acrylamide (AM), hydrophobic monomer allyl group dodecylamine and salt tolerant monomer H-66 as raw materials. The polymer structure was characterized by 1H NMR and FTIR, and the association effect of RDTA in different solutions and the relationship between the association behavior and temperature changes were studied through apparent viscosity, SEM, and rheological properties tests. The experimental results indicate that the critical association mass fraction (W*) of RDTA is between 0.25% and 0.3%. The stimulation effect of salt ions on RDTA polymer chains can enhance the structural viscosity of the molecular chain. The elastic modulus G" increases with the increase of RDTA mass fraction, and the solution system exhibits elasticity, resulting in a more dense spatial structure. At 70℃, 90℃, and 120℃, under 170 s-1 shear, when the shear time of 0.5% RDTA in 6% NaCl salt solution is less than 300 s, the viscosity of the solution shows a slow upward trend, indicating that RDTA has a phenomenon of salt stimulating RDTA solution thickening in NaCl salt solution. After further shear for 1 hour, the remaining viscosity after shear is still above 60 mPa·s.