POLYMER
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2023
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IF 4.6
Xinlan Hu,Yanyun Li,Hongfeng Chen,Jue Cheng,Qingsong Lian
Dispersion of Graphene (GE), high cost of massive usage of GE, and synergistic efficiency of GE and other fillers on epoxy resin (ER) are still challenges. This work not only achieves the uniform dispersion of few-layered GE through π-π interaction between GE and phenyl glycidyl ether (PGE), but also presents an equation in calculating the synergistic efficiency of multiple tougheners. The results show that the strength , modulus, elongation at break, and impact strength of ER can be simultaneously improved when D8 (an epoxy resin with side aliphatic chains) and PGE/GE are used together (D8/PG-X samples) or alone, and the D8/PG-X samples exhibit incomparable positive synergistic efficiency in both strength and toughness with ultralow GE content. The improvement of the impact strength , elongation at break, tensile modulus , and tensile strength in the optimum D8/PG-5 system is 115.5 %, 45.7 %, 17.8 %, and 28.3 % compared with unmodified ER system. We demonstrate that the improved comprehensive properties of the D8/PG-X samples as well as the improved interlaminar shear strength (ILSS) of the carbon fiber (CF)/ER composites can be ascribed to synergistic strengthening-toughening effect of self-assembly effect of aliphatic chains in D8 and uniformed dispersed GE (by π-π interaction). The impressive synergistic strengthening-toughening strategy can provide theoretical guidance for the preparation of high-performance ER with ultralow GE content.
研究领域:
材料科学
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复合材料
✓ 已验证
产品关联
DOI
高影响因子
INDUSTRIAL & ENGINEERING CHEMISTRY RESEARCH
·
2024
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IF 3.8
Yuming Bo,Anru Guo,Baojiang Hou,Heng Zhao,Baochen Han,Dong Liu
Simultaneously achieving high strength and toughness is a dilemma for most high-performance materials, especially solidified epoxy resins (ERs). Here, we used a sustainably sourced tannic acid (TA) molecule, a natural polyphenol hyperbranched polyester, as both a reinforcing and toughening agent for preparing high-strength epoxy adhesives with increased toughness. Benefiting from a highly branched structure and abundant active phenolic hydroxyl groups, TA molecules can be functionalized as multiple physiochemical cross-linking points for generating high-performance ERs. The optimal TA-modified ER (TA/ER-3) shows a high tensile strength of 112.2 ± 3.6 MPa and a high elongation at break of 3.7 ± 0.20%, illustrating increased tensile strength by 37.2% and elongation at break by 32.4% compared with pristine ERs, respectively. Combining scanning electron microscopy and dynamic mechanical analysis reveals that the TA molecules not only promote the curing and cross-linking reaction of epoxy resin but also possess good interface interaction with the matrix, which tune the cross-linking density and dissipate fracture energy through deformation, resulting in strengthening and toughening ERs. This work offers sustainably sourced additives for developing high-performance epoxy adhesives, which can be extended to reinforce other types of polymers or nanomaterials.
研究领域:
材料科学
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化学工程
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环境科学
✓ 已验证
产品关联
DOI
高影响因子
MATERIALS LETTERS
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2023
·
IF 3
Xiaobao Li,Wenxia Xia,Liming Shen,Weiming Tan,Xinliang Luo
To improve the mechanical properties of epoxy resin (EP), cellulose nanoparticles (CNP)/EP composites were prepared using an in-situ reaction method. Fourier-transform infrared spectroscopy analysis showed that cellulose nanocrystalline (CNC) decomposed into CNP in the reaction, and grafted with epoxy resin E44. Environmental scanning electron microscope analysis showed that the CNP had good interfacial compatibility and dispersion in the EP. TEM analysis showed that the CNC decomposed into CNP during the process of copolymerization with epoxy resin E44, and the size of the CNP was around 50–100 nm. With the addition of 0.3 wt% CNC, the tensile strength of the CNP/EP composite film increased by 24%, the tensile modulus increased by 26%, the elongation at break increased by 61%, and tensile toughness increased by 101%. Therefore, in this work, we presented a novel cellulose nanoparticle to simultaneously strengthen and toughen epoxy resin.
研究领域:
材料科学
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化学工程
✓ 已验证
产品关联
DOI
高影响因子
POLYMER
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2018
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IF 3.483
Zhilong He,Jiacheng Sun,Li Zhang,Yaqi Wang,Huiyan Ren,Jin-Biao Bao
Synergistic reinforcing and toughening of polydicyclopentadiene (PDCPD) nanocomposites reinforced with multi-walled carbon nanotubes (MWNTs) were achieved and enhancing mechanism was investigated. MWNTs were functionalized with vinyl groups via chemical grafting and the vinyl groups functionalized MWNTs (f-MWNTs) were characterized by fourier transform infrared spectroscopy and field-emission scanning electron microscopy. The mechanical properties of f-MWNTs/PDCPD composites were investigated by means of universal testing, notched izod impact testing and dynamic mechanical analysis . Synergistic improvement of yield strength, tensile toughness and impact strength of composites were observed with the incorporation of 0.1–0.4 wt% f-MWNTs compared with pure PDCPD. The maximum yield strength, toughness and impact strength of the composites increased by about 48%, 94% and 97%, respectively. The simultaneous enhancement is probably ascribed to MWNTs’ excellent mechanical properties and high aspect ratio, short and flexible vinyl groups onto MWNTs surface, strong covalent bonds between PDCPD and f-MWNTs.
研究领域:
材料科学
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复合材料工程
✓ 已验证
产品关联
DOI
高影响因子
MACROMOLECULES
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2023
·
IF 5.5
Fengbo Zhu,Shanhao Feng,Zequn Wang,Zhichao Zuo,Shilei Zhu,Wenwen Yu,Ya Nan Ye,Meng An,Jin Qian,Zi Liang Wu,Qiang Zheng
Polyelectrolyte (PE) hydrogels are ubiquitous in nature. Tailoring the interactions between PE gels and salt provides versatile implements to overcome their critical drawbacks such as weak and brittle nature. Adding salts to PE gels introduces both counterions and co-ions, and the variations of PE chain conformations and their macroscopic properties have been mainly attributed to the interplay between PE charged groups and their counterions, yet the role of co-ions is generally ignored. This work demonstrates that by changing co-ion species with larger atomic sizes, monovalent haloids are capable of triggering the phase separation of common poly(acrylic acid) single network (PAAc-SN) hydrogels into polymer-sparse and polymer-rich regions, accompanied by remarkable enhancement in strength and toughness. The capabilities of co-ions inducing phase separation of PAAc-SN gels follow a reverse Hofmeister series: Cl– < Br– < I–. Due to the enhanced polymer–polymer interactions and viscoelastic energy dissipation, the phase-separated PAAc-SN gels exhibit exceptional mechanical properties, with fracture stress and tearing energy of 96.7-folds and 1636-folds larger than those of the as-prepared gels, respectively. The largest fracture stress and tearing energy reach 8.8 ± 1.3 MPa and 29.8 ± 2.4 kJ/m2, exceeding most state-of-the-art PE hydrogels. A combination of FTIR, 1H NMR, and all-atom molecular dynamics simulations reveals that the reverse Hofmeister series-aided phase separation originates from changes of network chain conformation through the following influences rooted in the larger size of co-ions: (i) enhancing hydrophobic polymer–polymer interactions; (ii) accelerating the ion pair formation between carboxyl groups and their sodium counterions. These results not only provide a new method for hydrogel strengthening and toughening but also emphasize the significant role of co-ions in tuning the properties of PE gels.
研究领域:
材料科学
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高分子化学
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软物质物理
✓ 已验证
DOI
高影响因子
ACS Sustainable Chemistry & Engineering
·
2025
·
IF 7.3
Qiushuang Zhang,Wenwen Qiu,Wanjie Zhang,Lifu Yin,Chengwei Lin,Jianquan Wang
As a class of nanocellulose, cellulose nanospheres (CNSs) attract increasing attention due to their unique spherical morphology with larger surface areas, and the development of functional CNS from industrial cellulose derivatives is very promising for their resourceful utilization. In this work, nitrocellulose (abbreviated as NC) was used as a raw material to prepare functional CNSs with tunable sizes via facile denitration, followed by ultrasonication in an aqueous system. The reaction conditions of NC denitration were optimized by orthogonal experiments, and four CNS samples with different degrees of nitration (DoNs) were obtained by changing the NaHS concentration for denitration. The generated CNS samples were featured with a cellulose II-like structure, and their sphere sizes as well as crystallinity indices increased with a decrease in the DoN. One CNS sample with the most residual nitro groups (CNS-0.8) in this study demonstrates excellent strengthening and toughening effects to the poly(n-butyl acrylate) (PBA) matrix at a dosage of only 2 wt % owing to its good dispersity and compatibility in PBA. This presentation not only proposes a simple and green strategy to fabricate functional CNSs compatible with some hydrophobic polymer matrixes but also provides a feasible solution for the resourceful utilization of NC.
研究领域:
高分子材料
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纳米纤维素
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生物基材料
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复合材料科学
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绿色化学
✓ 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）