摘要
聚合物分子空间构型从一维线型向三维体型转变,是改变传统油田化学处理剂分子设计的新思路,有利于新型多功能水基钻井液聚合物处理剂开发。为阐明体型高分子形态特征及其作为钻井液处理剂的有效功能,采用实验合成、结构表征、性能评价与分子模拟相结合的方法,系统开展了微球聚合物PAA-AM-AMPS强化水基钻井液稳定性研究。首先,合成了具有体型结构的微球聚合物PAA-AM-AMPS,评价了微球聚合物微观结构及其在恒流变和超高温水基钻井液体系的核心作用;然后,基于体型高分子基团空间分布的“补偿效应”模型,从分子水平揭示了体型构象对高分子-膨润土片层吸附的强化作用。研究结果显示:合成体型聚合物PAA-AM-AMPS是一种具有核-壳结构的微球粒子,平均粒径为198.3 nm;微球聚合物热解分为5个阶段,空间构型展示了良好热稳定性;微球聚合物分子具有内紧外疏的空间构型,活性基团—COOH、—CO(NH2)、—SO3H在球壳上的分布确定了体型结构活性位点,其中羧基C=O是主导活性基团;比较了链型和球型聚集态结构,后者具有更小的回转半径Rg和更大的径向分布函数g(r),显示了球型构象不仅提高结构的温度稳定性,也有利于维持壳层有效活性基团数量,确保与黏土片层的吸附缔合作用,最终提高水基钻井液宏观性能的稳定。
The spatial configuration transformation of polymer molecules from linear one-dimension to spatial three-dimension is a new clue for the molecular design of oilfield chemical additives through modification of conventional oilfield chemicals,and this method is beneficial to the development of new multi-functional polymeric water-based drilling fluid additives.To illuminate the morphological characteristics of the spatial polymers and the effective functions of these polymers as drilling fluid additives,studies on strengthening the stability of water based drilling fluids with polymer microsphere PAA-AM-AMPS are systematically conducted using methods such as experimental synthesis,structure characterization,performance evaluation and molecular simulation.First,the polymer microsphere PAA-AM-AMPS is synthesized.The microstructure of the polymer microsphere as well as the core role that the polymer microsphere plays in constant-rheology and ultra-high-temperature water based drilling fluids are examined.Then,based on the model of the“compensation effect”prevailed in the spaces of the spatial polymer groups,the strengthening effect of the spatial configuration on the adsorption of polymer molecules onto the bentonite layers is revealed from molecular point of view.The study shows that the synthesized spatial polymer PAA-AM-AMPS is spherical with a core-shell structure,with an average particle size of 198.3 nm.Its thermal degradation includes 5 steps,and the spatial configuration shows good thermal stability.The polymer microsphere molecule has a spatial configuration of“internal compactness and external sparsity”.The distribution of the active groups such as—COOH,—CO(NH2)and—SO3H on the shell of the microsphere determines the active position of the spatial structure.In these groups,the carboxyl group C=O is the dominant active group.Comparison of the chain and spheric structure shows that the spheric structure has smaller gyrational radius Rg and bigger radial distribution function g(r),indicating that the spheric configuration not only improve the thermal resistance of the structure,it also is beneficial to the retention of the number of the active groups on the surface of the shell,thereby ensuring the adsorption and association between the polymer molecules and the clay particles,and thus improving the stability of the macro-properties of the water based drilling fluid.
作者
许林
许力
吴舒琪
包宇
王晓棠
沈佳敏
孟双
王浪
XU Lin;XU Li;WU Shuqi;BAO Yu;WANG Xiaotang;SHEN Jiamin;MENG shuang;WANG Lang(School of Petrochemical&Environment,Zhejiang Ocean University,Zhoushan 316022;School of Chemistry and Chemical Engineering,Queen’s University of Belfast,Belfast BT95AG,UK;College of Petroleum Engineering,Yangtze University,Wuhan 430100)
出处
《钻井液与完井液》
CAS
北大核心
2023年第6期693-702,共10页
Drilling Fluid & Completion Fluid
基金
舟山市科技计划项目“海洋油气井密封损伤的压力控释靶向修复技术研发”(2019C21006)
浙江省基础公益研究项目“海洋油气开发微泄漏压差激活密封剂及其自适应修复机理研究”(LGG20E040002)。
关键词
微球聚合物
水基钻井液
流变稳定性强化
构效关系
分子模拟
Polymer microsphere
Water-based drilling fluid
Strengthening of rheology stability
Structure-activity relation
Molecular simulation
