Polymers
·
2024
·Vol. 16
·期 12
·1614
·
IF 4.7
Daqi Li,Shuyang Gao,Zhichuan Tang,Huimei Wu,Yayun Zhang
The development of micro cracks in shale formations can easily lead to wellbore instability caused by liquid phase invasion. In order to effectively seal the shale micropores, the surface treatment of nano-SiO2particles was developed using the silicane coupling agent A-1891. Then, the temperature-sensitive polypenic acrylamide polymer was modified onto the surface of the nanoprocal particle through reaction to obtain the nanosomal blocking agent ASN. The infrared spectrum shows that there are chemical bonds between the generated polymer chains, rather than simple physical composites, indicating the successful synthesis of the temperature-responsive nanosealing agent ASN. The particle size analysis showed that the synthesized nanoparticles in ASN have a uniform particle size distribution and display no agglomeration phenomenon. Applying ASN as a sealing agent in drilling fluid effectively fills the nanoscale micropores and microcracks in shale, making shale denser and significantly improving the wellbore stability of shale formations. In addition, it has good temperature resistance, can adapt to reservoirs at different temperatures, is non-toxic and environmentally friendly, and has good prospects for stable applications in shale formation wellbore.
研究领域:
石油工程
·
材料科学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
COMPOSITES PART B-ENGINEERING
·
2020
·
IF 7.635
Xingang Wang,Zhongfa Chen,Wei Xu,Xingjing Wang
Fluorescence labelling and self-healing microcapsules (FLSM) with fluorescein sodium labelled epoxy resin as core materials and urea-formaldehyde resin as shell materials were synthesized by in situ polymerization via ultrasonic dispersion. Micromorphology, chemical structure , thermal stability and reactivity of FLSM were studied by ESEM , FTIR, TGA and DSC . Laser scanning confocal microscopy (LSCM) was served to characterize the surface microcracks repair process of cement paste mixed FLSM. The results showed that FLSM with full spherical particles and a certain roughness on the surface were well dispersed in the range of 150–300 μm of particle size. The addition of fluorescein sodium has no significant effect on the micromorphology, chemical structure, thermal stability and reactivity of FLSM. After being cut by the blade, the fluorescence width of FLSM increased from 9 μm to 22 μm within 0–12 h. The core materials of FLSM was basically lost, which indicated that the core materials had good fluidity. When the microcracks occur on the surface of cement paste, FLSM can not only detect the specific location of the microcracks and repair them, but also infer the width of the microcracks. It provides a new method for detecting and repairing microcracks on the surface of cement matrix .
研究领域:
材料科学
·
建筑工程
✓ 已验证
产品关联
DOI
高影响因子
Geoenergy Science and Engineering
·
2025
·
IF 4.6
Xu Liang,Ke Xu,Qingzhong Zhu,Dingwei Weng,Pinhong Zhu,Cunchuan Zheng,Wei Wang
Due to the contradiction between the size, sedimentation of proppants and the complex fracture network created by low-viscosity fluids, fractures of various sizes are difficult to be effectively supported through traditional hydraulic fracturing technology, thus the in-situ self-propping fracturing fluid (ISSPFF) technology came into being. This technology only injects liquid into the wellbore to create fractures, autogenous proppants (APs) are then formed in the reservoir in situ with the increased temperature, which greatly improves the efficiency of reservoir stimulation. Herein, styrene is first selected as the polymerization reaction monomer for the synthesis of a novel ISSPFF system and the corresponding APs. Owing to the reduced interfacial energy, a stable water/oil dispersion system of the ISSPFF is formed, further confirmed by the molecular dynamics simulation. By optimizing component concentrations, the synthesized APs exhibit remarkable properties of uniform particle size, enhanced compressive strength, high conductivity, and long-term stability, better than those of the quartz sand. On this basis, the solidification behavior of the ISSPFF system with formation fluids, core column, crustal stress, and narrow fractures is thoroughly explored. The ISSPFF system can effectively open and support the microfractures with the average permeability and Kirschner permeability increased by 18 times and 42 times, respectively, revealing its great potential in improving the conductivity of microfractures. As a result, the developed ISSPFF system is highly expected to be applied in hydraulic fracturing for unconventional reservoir stimulation.
研究领域:
石油工程
·
材料科学
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF MOLECULAR LIQUIDS
·
2025
·
IF 5.2
Dongzhi Wang,Yanji Zhu,Hongda Zhou,Xinyu Bu,Huaiyuan Wang
Reducing the microcracks in concrete materials is critical for extending service life and improving safety in civil engineering. Despite much progress in self-healing concrete materials, the meticulous research in healing mechanisms is still inadequate. In this paper, self-healing microcapsules are prepared by in-situ polymerization method and the interfacial enhancement healing mechanism of microcracks based on organic–inorganic interpenetrated network is proposed. The epoxy resin, as core material, was encapsulated by urea–formaldehyde resin to prepare self-healing microcapsules (PUF-E). The microcapsules were pre-embedded in concrete composites to achieve healing of microcracks. The concrete composites containing 5 wt% PUF-E microcapsules demonstrate significant self-healing efficiency, which can completely repair microcracks and improve mechanical strength. The compressive and flexural strengths of the healed concrete are 22.36 MPa and 3.73 MPa, with recovery rates of 98.90 % and 112.69 %, respectively. The self-healing mechanism with triple enhancement reactions is investigated. On the one hand, the rapidly releasing epoxy resin from PUF-E microcapsules fills microcracks and cures to form the first polymer network. Subsequently the second inorganic skeleton is introduced through the hydrogen bonding between epoxy and inherent hydration products (calcium silicate hydrate), building an interpenetrating structure with the polymer network. On the other hand, the coordination interaction between epoxy groups and Ca 2+ further improves the strength of the interpenetrating structure and enhances interfacial adhesion, achieving excellent self-healing performance of the concrete composites. The interface-enhanced healing mechanism of organic–inorganic interpenetrated networks provides new ideas for the design and development of high-performance self-healing concrete materials.
研究领域:
土木工程材料
·
材料科学
✓ 已验证
产品关联
DOI
高影响因子
POLYMER SCIENCE SERIES B
·
2017
·Vol. 59
·期 3
·292-299
·
IF 0.621
Wang Chunyu,Bu Yuhuan,Zhao Letian
Water and oil dual-absorption materials for application in oil well cement for self-healing micro creaks has been synthesized through bicontinuous microemulsion polymerization. Bicontinuous structure of microemulsion was used to implement the performance of absorbing both water and oil. Phase behavior of the microemulsion system was analyzed by “ε–β fish-shape phase diagram” from which middle phase line was obtained to provide the formula of polymerization. The product was characterized using scanning electron microscope (SEM), pore size distribution (BET), water/oil absorption rate test and water/oil absorption speed test. SEM analysis showed that neither water absorption component nor oil absorption component formed separated particles, while they formed continuous component respectively. Due to the bicontinuous structure and pores, the materials have fast water and oil absorption rate.
研究领域:
材料科学
·
化学工程
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF INDUSTRIAL AND ENGINEERING CHEMISTRY
·
2023
·
IF 6.1
Xiaona Huang,Hao Zhang,Xuguang Wang,Xiutian Yang,Rongzhuang Lin,Fan Zhang,Ying Liu,Kun Xu,Chao Zhou,Pixin Wang
During cementing construction, H 2 S gas leak from micro-cracks of cement ring or cementing interface, seriously damaging wellbore integrity and shortening the life of wells. Therefore, microcrack self-healing cement technology is of great significance for oil wells to maintain the durability of cement rings and adapt to complex underground environments. Herein, acrylamide (AM), acrylonitrile (AN) and N-vinylformamide (NVF) were used as functional monomers , and laponite was added to prepare Laponite-poly(acrylamide-acrylonitrile-n-vinylformamide) nanocomposite hydrogel (L-PMAN) with excellent mechanical strength as micro-crack repair agent for gas-triggered cementing cement sheath. Considering the difference of chemical environment in the process of wellbore cement slurry sealing and subsequent micro-fracture plugging, different structural units were selected to design amphoteric structure. The construction of zwitterionic structure makes it exhibit excellent swelling behavior in salt solution while maintaining 80% of the original mechanical strength. More importantly, after adding L-PMAN powder,cement stone (C 1 ) can achieve good repair of microcracks under the trigger of H 2 S within 3 days, and the maximum gas breakthrough pressure can reach 2.5 MPa, indicating the great potentials of the L-PMAN for plugging microcracks in cement sheath.
研究领域:
材料科学
·
石油工程
✓ 已验证
产品关联
DOI
高影响因子
Coatings
·
2024
·Vol. 14
·期 4
·387
·
IF 2.9
Liang Yang,Xiang Chen,Linhao Gu,Yan Chen,Shuang Shi
A new kind of modified emulsified bitumen used to plug a microcrack was studied. The sizes of high-temperature emulsified bitumen were fit for the sizes of the microcrack, which were approved by the scanning electron microscope and laser particle size analyzer. Some tests have been designed to demonstrate that the polymer could be used to promote the softening point of modified asphalt, and the high-temperature emulsified bitumen has also shown an excellent performance in terms of static filtration, the viscous coefficient, and extreme pressure lubrication, as well as to inhibit ting shale expansion. The permeability recovery could reach 88.26%, which meets the specification requirements. The mud cake, which was formed by high-temperature emulsified bitumen as an additive, was thin, tough, and dense, which was proved by the scanning electron microscope. The process used to obtain this additive was simple, and the performance of the plugging microfracture was excellent, so this kind of plugging agent could have a better application future.
研究领域:
材料科学
·
石油工程
✓ 已验证
DOI
高影响因子
REACTIVE & FUNCTIONAL POLYMERS
·
2022
·
IF 4.966
Xiaona Huang,Yinchuan Wang,Xuguang Wang,Xiutian Yang,Hao Zhang,Fan Zhang,Chao Wang,Yungang Bai,Ying Liu,Jiarui Wang,Xinyue Wang,Hui Chi,Chao Zhou,Kun Xu,Pixin Wang
During the completion of a natural gas well , the annular gas migration of the cement paste significantly damages the cement quality. Thus, the cement with self-repairing property has great significance in oil well applications. In this work, chemically cross-linked hydrogels were synthesized by the solution polymerization of acrylamide , acrylic acid , and 2-(dimethylamino)ethyl methacrylate (DMAEMA) with NMBA as cross linker to plug the CO 2 -triggered microcracks in the cement paste. The mechanical strength of the hydrogel (Cu-PMAD) was significantly enhanced by complexation between Cu 2+ and the carboxyl group of the hydrogel network. As a self-healing plugging material, Cu-PMAD hydrogel powder was mixed with cement to prepare self-repairing cement slurry. The amphoteric structure of hydrogel was triggered by CO 2 due to the DMAEMA unit of the hydrogel was protonated, and the hydrogel can swell further by the anti-polyelectrolyte effect under CO 2 of nature gas and formation salt-bearing fluid. The good swelling ability and mechanical properties endowed the Cu-PMAD hydrogel with excellent plugging ability for cement microcracks triggered by CO 2 .
研究领域:
材料科学
·
石油工程
✓ 已验证
产品关联
DOI
高影响因子
Energy Reports
·
2023
·
IF 5.2
Xingxing Ding,Qing You,Jianfa Wu,Jian Zhang,Jiawei Liu,Caili Dai,Ning Sun,Linan Wei,Yongpeng Sun
With high clay content in shale gas reservoir, the hydration is easy during hydraulic fracturing, which will affect the fracture conductivity and productivity of gas wells. The illite content of the Longmaxi formation shale in Yongchuan District is high (more than 80% of clay mineral content), and gas wells have a high productivity after fracturing and shut-in. However, the hydration effect mechanism of fracturing fluid on illite rich shale is not clear. Therefore, in this paper, core hydration experiments are performed for the illite rich shale reservoir. The water imbibition characteristic of near-fracture shale is obtained, and the micro-morphology and microfracture development characteristics of hydration are studied. Moreover, the hydration mechanism of near-fracture shale is then explored from the aspects of ion diffusion and mineral interlayer spacing variation. It is deduced that the fracturing fluid is spontaneously imbibed into small pores preferentially during well shut-in after fracturing. After the near-fracture shale is touched by water, some clay minerals peel and fall off from the fracture surface after hydration, accompanied by the development of microfractures. The interlayer spacing of clay minerals expands (smectite expands by 8.8% and illite 1.5%) after water immersion, and the ion diffusion occurs. The first 15 h is the rapid diffusion stage (surface effect), while the second 15 h is the stable rising stage (internal effect). This study systematically analyzes the hydration characteristics of near-fracture illite rich shale and reveals its hydration mechanism, which are crucial for the optimization of well shut-in time and exploitation system of shale gas reservoir after fracturing.
研究领域:
石油工程
·
地质学
✓ 已验证
产品关联
DOI
高影响因子
Arabian Journal of Chemistry
·
2023
·
IF 6
Baimei Dai,Peng Xu,Mingbiao Xu,Qisheng Jiang,Qinglin Liu,Siwei Wang
It is difficult to seal oil-based drilling fluids in the large pore and micro-fracture formation, and there are few suitable materials for the oil phase with good sealing ability at present. In order to solve the problem of the lack of sealing ability of oil-based drilling fluids, acrylamide, 2-acrylamido-2-methylpropane sulfonic acid, and acryloyl morpholine were used as monomers, N' N -methylenebisacrylamide was used as a cross-linking agent, Span-80 and Tween-60 were used as emulsifiers, and 2,2′-azobis(2-methylpropionamidine) dihydrochloride was used as an initiator. Polymer microsphere emulsion OPME was synthesized by inverse emulsion polymerization. The structure of polymer microspheres was characterized by infrared spectroscopy, scanning electron microscopy, electron microscopy, H NMR, laser particle size analysis and thermogravimetric analysis. The optimal synthesis conditions were determined by the control variable method: the monomer ratio of acrylamide, 2-acrylamido-2-methylpropane sulfonic acid, and acryloyl morpholine was 45:20:15, the amount of emulsifier was 8%, and the reaction temperature was 55℃. The synthetic polymer microspheres were added to the oil-based drilling fluids to perform filtration and loss plugging at atmospheric pressure and high-temperature and high-pressure, as well as pore and artificial fracture core plugging evaluation. The evaluation results show that the permeability reduction rate of pore core can reach 82%, and that of fracture core can reach 100% by adding polymer microspheres with 3% dosage. Finally, the pressure transmission experiment proves that the addition of polymer microspheres can slow the pressure transmission and filtrate intrusion, and enhance the stability of wellbore. Therefore, polymer microspheres are a micron-level plugging agent with good compatibility and high performance with oil-based drilling fluids, and the 3% dosage can better seal the formation of large pores and micro-fractures, which has a good potential for field application.
研究领域:
石油工程
·
材料科学
✓ 已验证
产品关联
DOI
高影响因子
FUEL
·
2025
·
IF 7.5
Hongtao Fu,Kaoping Song,Erlong Yang,Lihao Liang,Yu Zhao,Zhehui Jin
Shale oil is an unconventional energy resource, and its efficient development is a key focus of current energy research. China’s continental shale resources are abundant, with high clay content and poor physical properties. The development of shale oil reservoirs after horizontal well fracturing remains suboptimal, requiring further recovery enhancement. Surfactant imbibition oil recovery technology is recognized as one of the effective methods for enhancing oil recovery in unconventional reservoirs. This study proposes a novel experimental apparatus and method for dynamic imbibition, and also develops a three-dimensional (3D) micro pore-fracture dynamic imbibition model. Furthermore, surfactant selection criteria based on wettability and interfacial tension are established. The results show that Cetyltrimethylammonium bromide (CTAB) forms ion pairs on the surface of shale pores, rapidly removing the oil film covering the shale surface. This induces a wettability reversal, reducing the water-phase contact angle from 132° to 55.1°. The use of the CTAB surfactant solution resulted in an 11.5 percentage points improvement in final imbibition efficiency. After CTAB surfactant solution detaches oil droplets from the shale surface, more of the water phase comes into contact with the clay minerals and micro-damage structures in the shale. Hydration induces new micro-damage in the shale, which accumulate and evolve into micro-fractures, creating flow channels for shale oil transport. Another key mechanism for enhancing the dynamic imbibition efficiency of continental shale oil is to modify the shale surface wettability while strategically adjusting interfacial tension. The selection criteria for surfactants used in shale oil dynamic imbibition should require not only wettability alteration capability but also an appropriate interfacial tension ranging from 2 to 10 mN/m. This balances the promoting effect of capillary forces with the suppressing effect of the Jamin effect, thereby facilitating the movement of oil droplets within deformed pores. Significant variations in average pressure within the pores enhance micro dynamic imbibition efficiency in shale. In the practical development of shale oil reservoirs, providing effective short-cycle energy replenishment and altering the average pressure within shale pores are crucial for guiding the enhancement of recovery in continental shale oil reservoirs.
研究领域:
石油工程
·
非常规能源
·
储层物理
·
界面科学
·
提高采收率技术
✓ 已验证
产品关联
DOI
高影响因子
ARABIAN JOURNAL FOR SCIENCE AND ENGINEERING
·
2025
·
IF 2.9
Yang Chunming,Yu Mengjie,Wang Yuan,Liu Yang,Zhou Chunyuan,Shi Jieyi,Bao Dan,Zhong Cheng,Li Benhui,Li Yifan,Fan Yuzhu,Zhou Chengyu
Wellbore instability is a key challenge in drilling engineering, significantly affecting the efficiency and safety of oil and gas extraction. This study addresses the wellbore instability problem in the Shaximiao Formation and proposes a polyamine drilling fluid system based on micro-nanofillers sealing technology. The system’s efficiency and stability are verified through multi-scale characterization and performance optimization. Techniques such as X-ray diffraction (XRD), scanning electron microscopy (SEM), and contact angle measurement are employed to systematically analyze the mineral composition, microstructure, and surface properties of the Shaximiao Formation. It is revealed that the main cause of instability stems from the hydration expansion of clay minerals and the development of micro-cracks. Based on this, the synergistic effect of the micro-nanofiller sealing agent and the polyamine inhibitor is optimized to construct a high-performance drilling fluid system. Experimental results show that this system exhibits excellent rheological properties (API fluid loss < 5 mL, HTHP fluid loss < 10 mL), significant inhibition (rock sample recovery rate 96.79%, expansion rate < 4%), and long-term temperature stability (48 h). The micro-nanocomposite sealing structure effectively fills the micro-cracks in the formation and reduces pore pressure and permeability, thereby significantly enhancing wellbore strength. Compared to traditional drilling fluids, this system has significant advantages in sealing performance, inhibition, and high-temperature stability. This study provides crucial theoretical foundations and technical support for addressing wellbore instability and inadequate plugging performance of drilling fluids in unconventional reservoir drilling operations.
研究领域:
石油工程
·
钻井液技术
·
地层稳定性
·
纳米技术
·
储层岩石力学
✓ 已验证
产品关联
DOI
高影响因子
危险品化学品经营许可证（带存储）