微嵌段长度对疏水缔合聚合物流变性能的影响

Effect of Micro-block Length on Rheological Performance of Hydrophobically Associating Polymer

彭田杰 柳建新 赵众从 陈友准

PENG Tianjie，LIU Jianxin，ZHAO Zhongcong，CHEN Youzhun

为揭示疏水缔合聚合物结构与性能的关系，采用稳态应力扫描、剪切速率扫描、频率扫描等流变性实验方法，研究了疏水缔合聚合物（丙烯酰胺、丙烯酸钠和十二烷基丙烯酰胺共聚物，疏水单体十二烷基丙烯酰胺含量0.2 mol%）的微嵌段长度（NH）对其流变性能的影响规律。研究结果表明：随着微嵌段长度的增加，聚合物的缔合效应加强，更易于形成可逆空间网络结构；同时其临界缔合浓度（CAC）逐渐降低，会使其增黏能力、黏弹性能均有很大提升；当NH 从3.3 增至12.5 时，CAC 从1684 mg/L 降为846 mg/L，零剪切黏度从204.73 mPa·s 增至65833.19 mPa·s，松弛时间从0.07 s 增至12.64 s。流变实验结果表明，疏水缔合聚合物的缔合与解缔合是一个可逆的动态过程，微嵌段长度越长，经剪切作用破坏后的结构黏度重新恢复速度越慢，但其恢复后的黏度越高。在一定范围内升高温度和增加溶液离子强度有利于增强缔合效应，从而促使疏水缔合聚合物的抗温、抗盐性能在一定程度上提高。图8表1 参33

In order to discover the relationship between structure and performance of hydrophobically associating polymer, the effect of the length of the micro block length（NH） on the rheological properties of the hydrophobically associating polymer，a acrylamide-sodium acrylate-N-Dodecylacrylamide copolymer, containing 0.2 mol% N-Dodecylacrylamide hydrophobic monomer chain，was studied by using the method of steady state stress，shear rate and frequency scanning. The results showed that，with the increase of micro-block length，the associative effect of the polymer enhanced and the polymer solution was easier to form a space network structure，and the critical association concentration（CAC） decreased and thickening performance and viscoelastic properties were greatly improved .When NH increased from 3.3 to 12.5，CAC decreased from 1684 mg/L to 846 mg/L，and zero shear viscosity increased from 204.73 mPa·s to 65833.19 mPa·s，and relaxation time increased from 0.07 s to 12.64 s. The rheological experiments confirmed that the association and disassociation of hydrophobically associating polymer was a reversible dynamic process，the longer the micro block length，the slower the recovery rate of structural viscosity after shear damage，but the higher viscosity after the recovery. Under the same conditions，increasing the temperature and the ionic strength of the solution was beneficial to enhance the association effect within certain range，which resulted in enhancing the resistance to temperature and salt performance of associative polymer to a higher level.

10.19346/j.cnki.1000-4092.2016.04.020