Abstract Novel chloride-substituted octylphenoxy polyoxyethylene (COP20, polymerization degree: 20) was synthesized. Xanthan gum (XG) was then modified by using COP20 to produce XGP20. XGP20 could be expected to be applied in polymer flooding. Compared with XG, the XGP20 solutions exhibited lower interfacial tensions in additional to higher apparent viscosities and salt-thickening effect. Its critical micelle concentrations (CMC) were 0.3 g/L in water and 5 g/L NaCl at 30 °C, and the interface tension was 0.46 mN/m in the saline solution. Large associating structures formed in the XGP20 saline solution. The thermodynamic data of micellization revealed that the micelle formations were spontaneous from 30 to 50 °C. Both standard enthalpy and entropy increased clearly with temperature. Compared with XG, the resistance and residual resistance factors were evidently higher in 5.177 g/L salt for XGP20. Nuclear magnetic resonance images showed that the sweep efficiency of water was enhanced significantly after XGP20 polymer flooding.

中文翻译：

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两亲性改性黄原胶在水溶液中的聚集热力学行为和提高采收率的驱油性能

摘要 合成了新型氯代辛基苯氧基聚氧乙烯（COP20，聚合度：20）。然后通过使用 COP20 对黄原胶 (XG) 进行改性以生产 XGP20。XGP20有望应用于聚合物驱。与 XG 相比，XGP20 溶液除了具有更高的表观粘度和盐增稠效应外，还表现出更低的界面张力。其临界胶束浓度（CMC）在水中为 0.3 g/L，在 30 °C 下为 5 g/L NaCl，在盐水溶液中的界面张力为 0.46 mN/m。在 XGP20 盐水溶液中形成大的缔合结构。胶束化的热力学数据表明胶束的形成在 30 到 50 °C 是自发的。标准焓和熵均随温度明显增加。与XG相比，XGP20 在 5.177 g/L 盐中的抗性和残留抗性因子明显较高。核磁共振图像显示XGP20聚合物驱后水的波及效率显着提高。