Abstract: According to the mechanism of associative polymers forming large-size congeries through association of hydrophobic side chains, the association degree of the associated polymer was controlled using β-cyclodextrin with the amphiphilic structure, and the association degree of the associating polymer in porous media was indirectly calculated by the viscosity of polymer solution. Viscosity was used for evaluation of association degree of polymer in porous media indirectly. The paper provided a detailed experimental study of association behavior in porous media, including effect of β-cyclodextrin concentration on the polymer viscosity, congeries form, and association degree under different permeability. The results showed that β-cyclodextrin was only wrapped on the hydrophobic side chains of the associative polymer, but had no effect on the molecular backbone of associative polymer and the molecular structure of linear polymer. The contribution rate of association viscosity to apparent viscosity was more than 94%. The association degree of associative polymer in the porous medium increased with the increase of the permeability. The size of the aggregates formed by the association polymer was more compatible with the pore size of the core due to the presence of the association. The degree of association of the polymer in the core with permeability below 4 000 × 10-3 μm2 was less than 10%.

Key words: Associative polymer, Association degree, β-cyclodextrin, Evaluation methods, Porous media

摘要： 根据缔合聚合物通过疏水侧链的缔合作用形成大尺寸聚集体的作用机理，提出利用具有两亲腔体独特结构的β环糊精控制缔合聚合物的缔合程度，并利用聚合物溶液黏度间接计算缔合聚合物在多孔介质中的缔合程度。实验从β-环糊精质量分数对缔合聚合物黏度、聚合物聚集体形态、缔合聚合物在不同渗透率条件下的缔合程度几方面研究了缔合聚合物在多孔介质中的缔合行为。结果表明，β-环糊精仅对缔合聚合物的疏水侧链进行包裹，而对缔合聚合物分子主链和线性聚合物分子结构没有影响，缔合聚合物缔合黏度对表观黏度的贡献率超过94%。缔合聚合物在多孔介质中的缔合程度随渗透率增加而增加，同时由于缔合与解缔合作用的存在，缔合聚合物形成的聚集体尺寸更易与岩心孔喉尺寸相匹配，缔合聚合物渗透率在4 000×10^-3 μm²以下，岩心中的缔合程度均小于10%。

关键词: 缔合聚合物, 缔合程度, &beta, -环糊精, 评价方法, 多孔介质