Gels
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2025
·Vol. 11
·期 8
·578
·
IF 5.3
Yancheng Yan,Tao Tang,Biao Ou,Jianzhong Wu,Yuan Liu,Jingbin Yang
In petroleum exploration and production, lost circulation not only significantly increases exploration and development costs and operational cycles but may also lead to major incidents such as wellbore instability or even project abandonment. This paper constructs a polymer gel plugging system by optimizing high-molecular-weight polymers, crosslinker systems, and resin hardeners. The optimized system composition was determined as 1% polymer J-1, 0.3% catechol, 0.6% hexamethylenetetramine (HMTA), and 15% urea–formaldehyde resin. Experimental studies demonstrated that during the initial stage (0–3 days) at 120 °C, the optimized gel system maintained a storage modulus (G′) of 17.5 Pa and a loss modulus (G″) of 4.3 Pa. When the aging period was extended to 9 days, G′ and G″ decreased to 16 Pa and 4 Pa, respectively. The insignificant reduction in gel strength indicates excellent thermal stability of the gel system. The gel exhibited superior self-filling capacity during migration, enabling complete filling of fractures of varying sizes. After aging for 1 day at 120 °C, the plugging capacity of the gel system under water flooding and gas flooding conditions was 166 kPa/m and 122 kPa/m, respectively. Furthermore, a complete gel barrier layer formed within a 6 mm wide vertical fracture, demonstrating a pressure-bearing capacity of 105.6 kPa. This system shows good effectiveness for wellbore isolation and fracture plugging. The polymer gel plugging system studied in this paper can simplify lost circulation treatment procedures while enhancing plugging strength, providing theoretical support and technical solutions for addressing lost circulation challenges.
研究领域:
石油工程
·
钻井液
·
高分子科学
·
油藏工程
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产品关联
DOI
PubMed
高影响因子
JOURNAL OF APPLIED POLYMER SCIENCE
·
2020
·Vol. 138
·期 7
·49856
·
IF 2.52
Donglei Liu,Xufeng Dong,Huiying Liu,Yiping Zhao,Min Qi
Motivated by a need to replicate structural and viscoelastic properties of soft tissue, such as cartilage, the structural hydrogels with viscoelastic feature have been of interest in biomedical application. However, the effect of pore alignment on their viscoelastic properties has been largely underestimated. This work prepared cellulose nanocrystal (CNC)/collagen hydrogels with different pore orientations, including horizontally aligned pores, random pores and vertically aligned pores, and integrated them into a multilayered hydrogel with multi-structure which mimics cartilage construct. The stress relaxation rate (τ 1/2 ), creep rate (γ 1/2 ), storage modulus ( G′ ) and loss modulus ( G″ ) increased in the order of the vertical, random, multi-structural, and horizontal. G′ value of the horizontal increased up to 300% relative to the vertical in the strain amplitude and frequency sweep. Maxwell–Weichert and Variable Network Density models were used to explain phenomena, and the experimental curves fitted well with the theoretical models. These results reveal that the viscoelastic properties of hydrogel can be influenced by pore orientation except conventional component concentration.
研究领域:
生物材料
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组织工程
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生物力学
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高分子科学
·
再生医学
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DOI
高影响因子
LWT-FOOD SCIENCE AND TECHNOLOGY
·
2025
·
IF 6.6
Lihua Zhang,Yuli Ning,Yingying Xin,Yinjiao Wei,Xinfang Liu,Bakht Ramin Shah,Xiaofan Zhang,Wei Xu
This study investigates the effects and underlying mechanisms of freeze-thawing on the mechanical properties of Pickering emulsion gels composed of konjac glucomannan/κ-carrageenan (KGM/CRG) induced by K 2 CO 3 . The results showed that as the number of freeze-thaw cycles increased, syneresis and water loss during the squeezing of the gels significantly rose, while their shear strength gradually increased. After two freeze-thaw cycles, the gel exhibited maximum hardness. Microstructural analysis revealed that ice crystals disrupted the original gel network, leading to the aggregation of oil droplets and the dissipation of water. During freezing, the crystallization of water enhanced interactions among polysaccharide molecules, resulting in a more robust and denser KGM-CRG network. X-ray diffraction analysis confirmed an increase in the crystallinity of the gel following freeze-thaw cycle treatment. Furthermore, compared to fresh samples, the freeze-thawed emulsion gels displayed higher storage and loss modulus. These findings suggest that Pickering emulsion gels show increased mechanical properties after treatment. Additionally, this study illustrated the potential mechanisms by which freeze-thaw treatment modifies the microstructure of Pickering emulsion gels and influences their gel properties, providing a theoretical foundation for the design of emulsion-gel foods through freeze-thaw cycle treatment.
研究领域:
食品科学
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高分子科学
·
胶体与界面科学
·
材料工程
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产品关联
DOI
高影响因子
FOOD CHEMISTRY
·
2024
·
IF 8.5
Huajian Xu,Zhongtao Hu,Zongwei Hao,Changyue Deng,Xiaowen Pi,Binjia Zhang
The effects of amino acids with different R-groups, namely glutamic acid (GLU), glutamine (GLN), and theanine (THE), on the pasting and structure properties of corn starch (CS) were investigated. During gelatinization, GLU decreased viscosity of CS. GLN and THE increased pasting enthalpy of CS from 7.62 to 8.72 and 9.50 J/g, respectively. All starch-amino acid systems had higher storage and loss modulus. Amino acids could adhere to starch granule surface. After co-gelatinization, GLU increased short-range order degree of starch, while GLN and THE decreased. Both infrared spectroscopy and quantum computation showed that non-covalent interaction occurred between amino acids and starch. Molecular dynamics revealed that the interaction between GLU and starch weakened hydrogen bonding between starch and water, promoting cross-linking between starch chains. GLN and THE changed dihedral angle torsion of glycoside bonds, and mainly interacted with starch by electrostatic interaction (50.06 kJ/mol) and van der Waals force (50.30 kJ/mol), respectively.
研究领域:
食品科学
·
化学
·
材料科学
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产品关联
DOI
PubMed
高影响因子
JOURNAL OF DISPERSION SCIENCE AND TECHNOLOGY
·
2018
·
IF 1.454
Lujiao Shi,Yi Wei,Nan Luo,Tianwei Tan,Hui Cao
In the present study, cationic xanthan gum (CXG) was synthesized to enhance the rheological property of xanthan gum (XG) by attaching quaternary amine groups to the backbone of XG. The efficacy of the substitution was confirmed by FT-IR spectra and 13C NMR. The surface morphology was changed considerably as demonstrated by SEM. The examined rheological properties of XG and CXG include steady-state and dynamic rheological properties. The results show that quaternary amine groups are successfully grafted onto the XG molecule. Apparent viscosity, storage modulus, and loss modulus of CXG solutions are greater than those of XG solutions under the same conditions. It is moreover found that apparent viscosity and viscoelasticity increase with the degree of substitution. The data indicate that the modified XG has much better heat resistance.
研究领域:
化学工程
·
材料科学
·
流变学
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产品关联
DOI
高影响因子
INTERNATIONAL JOURNAL OF BIOLOGICAL MACROMOLECULES
·
2020
·
IF 5.162
Kulang Primo Sokiri Kiliona,Mengqin Zhou,Yan Zhu,Ping Lan,Ning Lin
Incompatibility of chitin nanomaterials with organic solvents is challenging in the design of the desirable organogels. The long hydrocarbon chains were covalently grafted on the surface of nanochitins, with the attachment of reactive allyl groups and improved dispersion in organic solvents. The reactive thiol groups of poly (ethylene glycol) were introduced into the allyl-nanochitin suspensions to produce the organogels by the thiol-ene click reaction. Attributed to the UV-induced cross-linking between the soft segments of thiolated−PEG and the allyl-nanochitin, the stable organogels with the storage modulus higher than the loss modulus by one order of magnitude were obtained, exhibiting the significant phase transition and mechanical enhancement on the rheological behavior. The combination of crystalline allyl-nanochitin and polymeric chains played a crucial role in the construction of the micro-network, attributing to the stability and mechanical strength of the organogels.
研究领域:
材料科学
·
化学工程
·
高分子化学
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产品关联
DOI
PubMed
高影响因子
COLLOIDS AND SURFACES A-PHYSICOCHEMICAL AND ENGINEERING ASPECTS
·
2020
·
IF 3.99
Alain Pierre Tchameni,Binqiang Xie,Hui Zhang,Lin Zhao,Mingwang Luo,Jiantai Wen
A novel thermo-thickening hydrophilic copolymer (CGBA) was prepared by free-radical copolymerization of sodium 2-acrylamido-2-methylpropane sulfonic acid (NaAMPS) with a newly-synthesized thermo-sensitive macromonomer (BA) and cross-linking N,N’-methylenebisacrylamide (MBA) in aqueous solution under optimal conditions. Its aqueous solution viscosity behavior with respect to temperature was preliminarily evaluated in comparison with its cross-linked sulfonated copolymer (CPAMPS) counterpart (without BA side-chains). Particular attention is dedicated to the thermo-thickening of the aqueous copolymer solutions as studied by the viscosity measurements . In pure water, and above 0.5 wt.%, CGBA manifested an abrupt macroscopic property above the critical association temperature ( T cass ), while CPAMPS exhibited shear-thinning behavior following an Arrhenius law under the same conditions. The composition and length of BA side-chains were identified as the key parameters to envision the self-assembling behavior of CGBA. The results obtained from complementary experiments, performed by proton nuclear magnetic resonance ( 1 H-NMR), Differential scanning calorimetry (DSC), and pyrene fluorescence showed the phase transition of BA side-chains above the T cass . In addition, well above the T cass (70 and 80 °C), the oscillatory shear experiments proved that the storage and loss modulus could be fitted with the single relation time Maxwell model at low frequencies. Furthermore, the magnitude of the thickening effect and the T cass could be modulated using external factors such as shear rates, salinity, and pH. This, in combination with the cost-effectiveness, and the need to further broaden the established theory of thermo-sensitive comonomer, make this copolymer especially interesting for application not only in polymer flooding, but also in drilling fluid.
研究领域:
高分子化学
·
材料科学
·
胶体与界面科学
·
石油工程
✓ 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）