双网络上临界溶液温度型深部调剖缓膨凝胶颗粒的制备及性能

Preparation and Evaluation of Dual-Network UCST-Type Deep Profile Control Slow-Swelling Particles

摘要:

以甲基丙烯酰胺（MAAm）、N,N-二甲基丙烯酰胺（DMAA）为单体，N,N-亚甲基双丙烯酰胺（BIS）和2,2-二乙氧基苯乙酮（I-2959）分别作为交联剂和引发剂，通过自由基聚合和浸泡法制备PMAAm/PDMAA双网络UCST型水凝胶，用于调剖堵水。采用SEM、FTIR、流变性能测试对水凝胶的形貌、氢键作用和温度响应性质进行了表征，并探究了其温度响应性的溶胀性能以及不同氢键供体摩尔浓度对于凝胶的机械性能的影响。结果表明，当氢键供体摩尔浓度与氢键受体摩尔浓度比为2时，制备的双网络UCST型凝胶具有较高的转变温度90 ℃，拉伸强度最大可达到13.8MPa，拉伸断裂伸长率为100.9%，压缩应变在80%下其压缩强度可达到最大4.7MPa，具有优异的力学性能。氢键协同作用下使凝胶具有UCST响应，使其能够在低温下抗溶胀，高温下吸水膨胀倍数可达40倍，并且拥有0.65MPa的突破压力，能够有效适用地层调剖堵水作用当中，对地层为开发深处油藏进行控水处理。

Abstract:

A dual-network UCST-type hydrogel (PMAAm/PDMAA) was prepared using methyl acrylamide (MAAm) and N,N-dimethylacrylamide (DMAA) as monomers, N,N-methylene bisacrylamide (BIS) as the crosslinker, and 2,2-diethoxyacetophenone (I-2959) as the initiator via free radical polymerization and soaking method. The gel was developed for profile control and water blocking applications. The morphology, hydrogen bonding interaction, and temperature-responsive properties of the hydrogel were characterized by SEM, FTIR, and rheological performance tests. Additionally, the temperature-responsive swelling behavior and the effect of molar concentration of different hydrogen bond donors on the mechanical properties of the gel were investigated. The results indicate that when the molar concentration ratio of hydrogen bond donors to hydrogen bond acceptors is 2, the prepared dual-network UCST-type gel exhibits a high transition temperature of 90 ℃. The maximum tensile strength can reach 13.8 MPa, and the tensile fracture elongation is 100.9%. Under a compression strain of 80%, the gel can achieve a maximum compressive strength of 4.7 MPa, demonstrating excellent mechanical properties. The synergistic hydrogen bonding interaction enabled the gel to exhibit UCST behavior, allowing it to resist swelling at low temperatures and to swell up to 40 times at high temperatures. It also had a breakthrough pressure of 0.65 MPa, making it highly suitable for deep profile control and water blocking in reservoir development for deep oil fields.