摘要：The dynamic covalent nature of imine bonds provides a facile avenue to develop stimuli-responsive emulsifiers and has attracted considerable interest. In petroleum engineering, the development of smart emulsifiers that can be switched on demand to achieve the reversible phase inversion of the invert emulsion drilling fluid (IEDF) can effectively aid in its removal during cleanup. To this end, a novel dynamic covalent surfactant (TA-CBA) that can precisely manipulate the emulsion type by responding to acid/base stimuli was synthesized through the Schiff base reaction between 1-tetradecylamine (TA) and 4-carboxybenzaldehyde (CBA). Evaluation of the surface tension and interfacial tension (IFT) showed that the imine-bonded product TA-CBA was a surfactant with strong IFT reduction ability. At pH 7.4, the prepared water-in-oil (W/O) emulsions were stable without any separated phases after storage for 48 h and even after high-temperature aging at 210 degrees C. As the pH decreased from 7.4 to 4, the emulsion inverted from a higher viscosity W/O emulsion to a lower viscosity oil-in-water (O/W) emulsion. Remarkably, after the pH was adjusted back to 7.4, the rheological parameters and stability of the emulsion could be triggered at the original W/O emulsion level. H-1 NMR and IFT measurements revealed that the reversible formation and breakage of covalent imine bonds led to the production of CBA and cationic amine salt (TA(+)), establishing the pH reversibility of the emulsion type and its rheological properties. Finally, we successfully formulated a reversible IEDF using TA-CBA as the sole emulsifier, which not only has reasonable rheological properties, filtration performance, and emulsification stability but also allows for easy cleanup. The IEDF can be phase-inverted into a water-soluble O/W emulsion drilling fluid at pH 4 and achieved a removal efficiency of 98.13 %. (C) 2022 Elsevier B.V. All rights reserved.

关键字：pH-responsive emulsifier; Dynamic covalent bond; Emulsion phase inversion; Reversible invert emulsion drilling fluid

ISSN号：0167-7322

卷、期、页：卷: 364

发表日期：2022-10-15

影响因子：6.165200

期刊分区（SCI为中科院分区）：二区

收录情况：SCIE（科学引文索引网络版）,EI（工程索引）

发表期刊名称：JOURNAL OF MOLECULAR LIQUIDS

通讯作者：王国帅,付玥,杨俊,董腾飞

第一作者：蒋官澄,贺垠博

论文类型：期刊论文

论文概要：王国帅,蒋官澄,付玥,杨俊,贺垠博,董腾飞，pH-responsive water-in-oil emulsions with reversible phase inversion behavior stabilized by a novel dynamic covalent surfactant，JOURNAL OF MOLECULAR LIQUIDS，2022，卷: 364

论文题目：pH-responsive water-in-oil emulsions with reversible phase inversion behavior stabilized by a novel dynamic covalent surfactant