Petroleum
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2026
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IF 3.5
Qi Feng,Chengwen Wang,Wenjian Yue,Chengli Wang,Tao Song
Cementing in deep and ultra-deep reservoirs often faces the critical challenge of additive degradation in high-temperature environments. Addressing this, 1-vinylimidazole (VM) was incorporated into the copolymerization of N,N-dimethylacrylamide, itaconic acid, and 2-acrylamido-2-methylpropanesulfonic acid to synthesize a tetrapolymer (PDVI). Using aqueous free radical polymerization optimized by response surface methodology, the resulting PDVI exhibited superior fluid loss reduction in high-temperature and high-salinity conditions. Compared to the control sample PDI, PDVI reduced fluid loss from 64.7 mL to 25 mL at 200°C and from 105.7 mL to 42.5 mL at 240°C, while maintaining filtration below 70 mL in 20% NaCl. Structural characterization via 1 H-NMR and FTIR, combined with TGA and aging tests, confirmed that VM’s rigid five-membered ring significantly enhanced thermal stability; molecular weight retention after aging at 220°C increased from 46.13% to 68.31%. Furthermore, DLS, SEM, and zeta potential analyses indicated that VM’s cationic nature facilitates robust polymer adsorption on cement particles. This mechanism ensures effective particle dispersion and the formation of a dense filter cake even under extreme conditions. These findings provide essential insights for developing high-performance polymeric additives for cementing in complex downhole environments.
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DOI
高影响因子
CERAMICS INTERNATIONAL
·
2019
·
IF 3.45
Shuang Yin,Senchuan Jiang,Limei Pan,Lin Guo,Zhenghao Zhang,Jingxian Zhang,Xiaoyun Li,Tai Qiu,Jian Yang
Herein, a low–toxic N, N–dimethylacrylamide (DMAA) system was used in preparation of porous Si 3 N 4 ceramics by aqueous gelcasting, and variations in microstructure and properties with solid loading and calcination temperature were systematically investigated. In the considered solid loading range of 28–44 vol%, all the slurries exhibited superior rheological properties (≤145 mPa⋅s at 95.40 s −1 for 44 vol% solid loading) perfectly suitable for casting. With increasing solid loading, a decreased bulk density (1.71–1.69 g/cm 3 ), volume shrinkage (37.73–13.77%) and flexural strength (46.56–26.75 MPa) of green bodies were obtained, exhibiting better mechanical properties than those derived from the conventional acrylamide (AM) system. Regarding Si 3 N 4 ceramics with various solid loadings, the increase in calcination temperature favored the phase transformation α→β–Si 3 N 4 and β–Si 3 N 4 growth, however, the increased solid loading exhibited an inhibiting effect on those since mass transport in gas phase was blocked due to the disruption of pore connectivity. The resulting microstructure changes imparted Si 3 N 4 ceramics increasing flexural strength (110.36–367.88 MPa), fracture toughness (2.54–5.03 MPa⋅m 1/2 ), as well as decreasing porosity (54.21–41.05%) and pore size (0.38–0.33 μm). This work demonstrates the potential research value of DMAA system in preparing high–performance porous Si 3 N 4 ceramics through gelcasting technique.
研究领域:
材料科学
·
陶瓷工程
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DOI
高影响因子
POLYMER
·
2026
·
IF 5.1
Shuai Huang,Ziqiang Xiang,Yuhao Zhu,Renfeng Gong,Yicheng Wang,Ruoyi Liu,Guanjun Liu,Qingshan Wu
The rapid evolution of high-power flexible electronics necessitates materials that concurrently enable efficient heat dissipation and high-precision thermal monitoring. Conventional ionogels suffer from intrinsically low thermal conductivity, which induces severe thermal hysteresis, fundamentally compromising their accuracy in dynamic thermal detection. Herein, rather than treating copolymer regulation or h-BN filling as isolated design elements, we propose a thermally coupled ionogel design aimed at reconciling two usually conflicting requirements: rapid heat equilibration and high thermoresistive sensitivity. P(DMAA-co-AAM)/h-BN composite ionogels are fabricated via in-situ UV-initiated free-radical polymerization, in which N,N-dimethylacrylamide (DMAA) and acrylamide (AAM) form a mechanically compliant and ion-transportable copolymer network, lithium bis(trifluoromethanesulfonyl)imide (LiTFSI) provides thermally activated ionic pathways, and hexagonal boron nitride (h-BN) nanosheets introduce filler-assisted thermal transport pathways. Systematic optimization reveals that a DMAA-to-AAM mass ratio of 3:1 with 20 wt% h-BN yields the optimal synergy among mechanical flexibility, thermal transport, and ionic conduction. The resulting composite achieves a thermal conductivity of 0.469 W/(m·K), representing a ∼160% enhancement over the pristine matrix, which effectively suppresses heat accumulation. Concurrently, the ionogel exhibits an ultra-high temperature coefficient of resistance (TCR) of −13.5%/°C and a thermosensitive coefficient (B value) of 3879 K within 0-20°C. Benefiting from the enhanced thermal transport performance, the dynamic thermal response speed of this series of ionogel sensors (30°C → 35°C) is significantly accelerated with the increase of h-BN loading: the T90 response time of the 10 wt%, 20 wt%, and 30 wt% h-BN samples is 32.40 s, 24.34 s, and 15.14 s respectively. Meanwhile, the devices can still maintain stable and reversible resistance switching characteristics over 50 heating-cooling cycles. This study achieves the synergistic enhancement of the thermal management and temperature sensing performance of the ionogel, providing an ideal material platform for the next-generation wearable electronic devices and intelligent thermal management systems.
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DOI
高影响因子
APPLIED CLAY SCIENCE
·
2022
·
IF 5.907
Qinglu Chang,Guoqing Liu,Zhanpeng Dong,Xia Miao,Miaomiao Hu,Jintang Guo
Fluid loss agent (FLA) was adopted to reduce the fluid loss of cement paste to ensure the safety of cementing construction. With the increase of exploration depth, FLA applied at high temperatures has been urgently required. To meet the cementing requirements at 240 °C, the FLA with organic/inorganic intercalated microstructure was prepared. Anionic polymer FLA (ADIS) was comprised of 2-acrylamido-2-methylpropane sulfonic Acid (AMPS), N , N -dimethylacrylamide (DMAA), Itaconic acid (IA) and Sodium p-styrene sulfonate (SSS). The organic-inorganic hybrid FLA (MgAl-ADIS-LDH) was prepared via intercalating ADIS into Mg/Al hydrotalcite (MgAl-NO 3 -LDH) interlayers . The intercalated microstructure was observed by SEM , TG results exhibited that the intercalation of polymer ADIS in MgAl-NO 3 -LDH enhanced the thermal stability of overall FLA. When applied in cement, the cement with MgAl-ADIS-LDH showed a small water loss of 36 mL at 240 °C. Moreover, the structure avoided the decrease in the compressive strength of hardened cement resulted from traditional polymer FLA. Compared with the cement contains 1.6% bwoc ADIS, the compressive strength of specimen with MgAl-ADIS-LDH increased by 20.5% after cured for 3 days.
研究领域:
材料科学
·
化学工程
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DOI
高影响因子
危险品化学品经营许可证（带存储）