水解AM/DMDAAC/AMPS聚合物用作饱和盐水钻井液的高温高压降滤失剂

Hydrolyzed AM/DMDAAC/AMPS Copolymer Functioning as Filtration Reducer for Brine Saturated Drilling Fluids under High Temperature and High Pressure

摘要:

通过氧化还原体系引发AM、DMDAAC、AMPS三元共聚，再用NaOH在85 ℃下水解三元共聚物，制得水解AM/DMDAAC/AMPS聚合物。通过IR、NMR表征聚合物的分子结构，用TGA测试聚合物热稳定性。水解度的增加提高了产物热稳定性，并改善了钻井液的表观黏度、塑性黏度和动切力。但水解度存在最佳值，使钻井液的API、HTHP滤失量降到最低。羧基含量最优的水解产物按添加量3.5%（质量分数）配制成膨润土质量分数5%、NaCl质量分数30%的钻井液，在200 ℃下热滚16 h后的API滤失量为14.0 mL，HTHP滤失量（180 ℃）为40.0 mL。

Abstract:

Abstract：Redox iniator was used to conduct the copolymerization of AM, DMDAAC and AMPS. The terpolymer was then hydrolyzed with NaOH under 85 ℃ to synthesize hydrolyzed polymer. The structure of terpolymer and hydrolysate was characterized by IR and NMR, while the thermal stability of those products was studied using TGA. The increment of hydrolysis degree not only improved the thermal stability of hydrolysate but also enhanced the apparent viscosity, plastic viscosity and yield point of drilling fluids. An optimum content of hydrolysis degree, however, was found to reduce both API and HTHP filtration to minimum values. Mud was prepared by adding hydrolyzed polymer with such an optimal proportion of COO- of 3.5 wt%, bentonite of 5 wt% and NaCl of 30 wt%. API filtration and HTHP filtration was 14.0 mL and 40.0 mL respectively, after the mud was rolled for 16 h under 200 ℃.