EUROPEAN POLYMER JOURNAL
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2025
·
IF 6.3
Xiyu Zhang,Aoxiang Ge,Yong Tang,Wei Wei,Xiaojie Li
The inherent brittleness and flammability of epoxy resin (EP) significantly limit its applications in high-performance fields. To address these challenges, a P-functionalized diphenyl-methylvinyl-copolysiloxane additive (DOPS) was synthesized via a simple method using diphenylsilane, dimethoxymethylvinylsilane, and 9,10-dihydro-9-oxa-10-phosphaphenanthrene-10-oxide (DOPO). This additive was incorporated into epoxy systems cured with 4,4′-diaminodiphenylmethane (DDM), effectively enhancing both toughness and flame retardancy. When the DOPS content reached 6.93 wt%, the DOPS-4 thermosets achieved a V-0 rating in the UL-94 test. Additionally, the total heat release (THR) and total smoke production (TSP) of the DOPS-4 sample decreased by 41.34 % and 39.04 %, respectively, compared to the neat EP thermoset. These improvements were attributed to the trapping effect of P-containing radicals and the formation of a P/Si-containing char layer, which effectively inhibited combustion and reduced smoke and heat release. In addition, the flexural and impact strengths of DOPS-4 were improved by 15.6 % and 95.3 %, respectively, compared to the neat EP thermoset. These enhancements were ascribed to the rigid phosphaphenanthrene segments and abundant flexible chains in DOPS. Moreover, the DOPS-modified epoxy thermosets still exhibited excellent thermal stability. In sum, this work provides a facile and effective strategy to enhance the toughness and flame retardancy of epoxy thermosets, offering promising potential for advanced material applications.
研究领域:
材料科学
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化学工程
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产品关联
DOI
高影响因子
Materials Today Communications
·
2024
·
IF 3.7
Gaoxi Cui,Tongyang Li,Ziyue Wang,Lujie Wang,Yuan Yu,Huaguo Tang,Zhuhui Qiao
Soft metal as the second phase to enhance the mechanical and tribological properties of Si 3 N 4 ceramics was a focus of current research. Limited by the doping method and the low melting point of the metal, there were often phenomena such as nonuniform distribution and melting overflow of the second phase, which seriously deteriorated the properties of Si 3 N 4 . In this study, Cu-containing Si 3 N 4 was prepared by in-situ method using copper citrate as the second phase additive. The highly dispersed second phase helped Si 3 N 4 achieve significant improvements in fracture toughness and tribological properties. The phase composition, microstructure, hardness, fracture toughness, and tribological properties of Cu-containing Si 3 N 4 were investigated. XRD results indicated that the reinforcement phase was in the form of Cu 3 Si. When the Cu 3 Si phase content was 3 wt%, the fracture toughness of Cu-containing Si 3 N 4 could be increased by 27.1 % compared to the Si 3 N 4 . When the Cu 3 Si phase content reached 12 wt%, the wear rate at room temperature was reduced by 59 % compared to the substrate. The toughing mechanism could be summarized as the crack bridging and deflection of the Cu 3 Si phase. The anti-wear mechanism could be concluded as the reduction of micro-cracks in the friction film with the participation of Cu 3 Si phase, thus reducing the loss in the friction process.
研究领域:
材料科学
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机械工程
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产品关联
DOI
高影响因子
Science China-Chemistry
·
2025
·
IF 9.7
Li Jiatian,Khan Abdul Qadeer,Zhao Weiqiang,Lai Zhipeng,Bao Qiankun,Rafique Muhammad,Ye Fazhi,Bai Jie,Zhou Qiang,Mai Liqiang,Wang Zongqian,Liu Enzhao,Zhou Xiang,Liu Zunfeng
The pursuit of biomimetic fibers with simultaneous high toughness and strength persists, despite their inherent trade-offs. However, for artificial spider silk based on gel fiber, it is still unclear for the molecular chain attributes related to the improvement of the strength and toughness. Here, a hydrogel fiber was prepared by mimicking the molecular structure of natural spider silk, and we delved into the molecular chain structure characteristics related to the strength, toughness and damping capacity of gel fiber, such as crosslinking density, molecular chain orientation and hydrogen bond interaction. The results indicate that a certain increase in crosslinking density and molecular chain orientation contributes to the enhancement of tensile strength, while the toughness and damping remain essentially unaltered. The thermal dissociation of hydrogen bond could enhance the toughness in a specific range, while the humidity destruction of hydrogen bond would reduce the toughness. Through well-regulation control of the weight ratio of polyacrylamide (PAM) to poly(acrylic acid) (PAA), the PAM@PAA gel fibers could reach maximum breaking strength of 1.02 GPa, maximum toughness of 149 MJ m −3 , and damping capacity of 95%. PAM@PAA gel fiber has demonstrated excellent wound healing performance and biocompatibility in vivo evaluation as a surgical suture, which indicates its potential in biomedical applications.
研究领域:
生物材料学
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分子生物学
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医学工程
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DOI
高影响因子
HIGH PERFORMANCE POLYMERS
·
2021
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IF 2.161
Hailong Li,Sipei Zhao,Li Pei,Zihe Qiao,Ding Han,Zhanxin Liu,Qingsong Lian,Guizhe Zhao,Zhi Wang
Polybenzoxazines are emerging as a class of high-performance thermoset polymers that can find their applications in various fields. However, its practical application is limited by its low toughness. The cyclic β-cyclodextrin and a newly synthesized derivative (β-cyclodextrin-MAH) were separately blended with benzoxazine to improve the toughness of polybenzoxazine. The results revealed that the maximum impact strength of the blend was 12.24 kJ·m−2 and 14.29 kJ·m−2 when 1 wt.% of β-Cyclodextrin and β-Cyclodextrin-MAH, respectively, were used. The strengths were 53% and 86% higher than that of pure polybenzoxazine. The curing reaction, possible chemical structures, and fractured surface were examined using differential scanning calorimetry, Fourier transform infrared spectroscopy, and scanning electron microscopy techniques to understand the mechanism of generation of toughness. The results revealed that the sea-island structure and the presence of hydrogen bonds between polybenzoxazine and β-cyclodextrin and β-cyclodextrin-MAH resulted in the generation of toughness. Furthermore, the curves generated during thermogravimetric analysis did not significantly change, revealing the good thermal properties of the system. The phase-separated structure and the hydrogen bonds present in the system can be exploited to prepare synergistically tough polybenzoxazine exhibiting excellent thermal properties. This can be a potential way of modifying the thermoset resins.
研究领域:
材料科学
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高分子化学
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产品关联
DOI
高影响因子
INTERNATIONAL JOURNAL OF BIOLOGICAL MACROMOLECULES
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2024
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IF 7.7
Xikun Zhang,He Zhang,Xue Lv,Ting Xie,Junzheng Chen,Di Fang,Shurui Yi
Conductive hydrogels , as novel flexible biosensors, have demonstrated significant potential in areas such as soft robotics, electronic devices, and wearable technology. Graphene is a promising conductive material , but its dispersibility in aqueous solutions exists difficulties. Here, we discover that untreated graphene, after exfoliation by different ionic liquids , can disperse well in aqueous solutions. We investigate the impact of four ionic liquids with varying alkyl chain lengths ([Bmim]Cl, [Omim]Cl, [Dmim]Cl, [Hmim]Cl) on the dispersibility of grapheme, and a dual physically cross-linked network hydrogel structure is designed using acrylamide (AM), acrylic acid (AA), methyl methacrylate octadecyl ester (SMA), ionic liquid@graphene (ILs@GN), and chitosan (CS). Notably, SMA, CS, AA and AM act as dynamic cross-linking points through hydrophobic interactions and hydrogen bonding , playing a crucial role in energy dissipation. The resulting hydrogel exhibits outstanding stretchability (2250 %), remarkable toughness (1.53 MJ/m 3 ) in tensile deformation performance, high compressive strength (1.13 MPa), rapid electrical responsiveness (response time ∼ 50 ms), high electrical conductivity (12.11 mS/cm), and excellent strain sensing capability (GF = 12.31, strain = 1000 %). These advantages make our composite hydrogel demonstrate high stability in extensive deformations, offering repeatability in pressure and strain and making it a promising candidate for multifunctional sensors and flexible electrodes.
研究领域:
材料科学
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生物医学工程
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产品关联
DOI
PubMed
高影响因子
CARBOHYDRATE POLYMERS
·
2023
·
IF 11.2
Lisong Hu,Yitong Xie,Shishuai Gao,Xiaoyu Shi,Chenhuan Lai,Daihui Zhang,Chuanwei Lu,Yi Liu,Lei Du,Xuezhi Fang,Feng Xu,Chunpeng Wang,Fuxiang Chu
Stretchable and tough polysaccharide-based functional hydrogels have gained popularity for various applications. However, it still remains a great challenge to simultaneously own satisfactory stretchability and toughness, particularly when incorporating renewable xylan to offer sustainability. Herein, we describe a novel stretchable and tough xylan-based conductive hydrogel utilizing the natural feature of rosin derivative. The effect of different compositions on the mechanical properties and the physicochemical properties of corresponding xylan-based hydrogels were systematically investigated. Owing to the multiple non-covalent interactions among different components to dissipate energies and the strain-induced orientation of rosin derivative during the stretching, the highest tensile strength , strain, and toughness of xylan-based hydrogels could reach 0.34 MPa, 2098.4 %, and 3.79 ± 0.95 MJ/m 3 , respectively. Furthermore, by incorporating MXene as the conductive fillers, the strength and toughness of hydrogels were further enhanced to 0.51 MPa and 5.95 ± 1.19 MJ/m 3 . Finally, the synthesized xylan-based hydrogels were able to serve as a reliable and sensitive strain sensor to monitor the movements of human beings. This study provides new insights to develop stretchable and tough conductive xylan-based hydrogel, especially utilizing the natural feature of bio-based resources.
研究领域:
材料科学
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生物工程
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产品关联
DOI
PubMed
高影响因子
COMPOSITES SCIENCE AND TECHNOLOGY
·
2021
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IF 8.528
Jiayao Yang,Hengxu Wang,Xiaohuan Liu,Shenyuan Fu,Pingan Song
The intrinsic brittleness has significantly restricted practical applications of epoxy resins. Existing toughening strategies often lead to degraded mechanical strength . Hence, it has been attractive but a huge challenge to design high-performance sustainable additives that can simultaneously improve strength and toughness of epoxy resins. Here, we report the synthesis of a nano-TiO 2 /regenerate cellulose (RC) biohybrid via a facile microwave method for strengthening and toughening a soft epoxy resin system (modulus below 1 GPa). Our results show that with 10 phr nano-TiO 2 /RC, the resultant epoxy composite exhibits simultaneous enhancements in tensile strength and impact toughness , ca. 38% and 40% higher than corresponding values of virgin epoxy resin because of improved interfacial compatibility. Moreover, the addition of as-designed nano-TiO 2 /RC can enhance thermostability of epoxy resin. It has a slightly negative effect on the curing reaction but does not change the curing mechanism of epoxy resins. This study provides a facile, efficient and green method for preparing bifunctional additive for creating strong and tough epoxy composites, which are expected to find wider applications in industries.
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
CARBOHYDRATE POLYMERS
·
2023
·
IF 11.2
Qingye Liu,Jianfeng Zhang,Yarui Hou,Xiaohui Wang,Xiaojun Li,Tie Chen,Xiaojuan Xu
The traditional κ-carrageenan (κCG)-based hydrogel obtained from hot water can rupture easily under mechanical loading. To address this vulnerability, here we presented a robust all-κCG hydrogel without employing the second synthetic network. By simply regulating the polymer chains from random coil to stiff chain conformation in NaOH/urea solvent system via the freeze-thawing process, the as-prepared hydrogel with homogeneous structure can display an enhanced stretchability from 42.1 to 156 %, while maintaining the similar fracture stress. Moreover, upon the stepwise mechanical training and subsequent incubation in KCl aqueous solution, more helical segments of κCG were aligned and involved into the association domains, thus leading to the increment in both the crystallinity and anisotropy. Consequently, a fast self-strengthening behavior occurred, and a more stretchable (fracture strain up to 396 %), strong (stress ∼ 0.55 MPa) and tough (∼1.52 MJ m −3 ) κCG hydrogel was obtained. In comparison to the traditional one, the fracture strain and toughness are increased by 8.5 and 11.5 times, respectively. In addition, this κCG hydrogel can demonstrate good recovery and shape-memory behaviors under medium deformation. Hence, this tough all-κCG hydrogel is expected to be tailored into the biomaterials as the wearable device, artificial tendon, and cartilage in the future.
研究领域:
材料科学
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生物医学工程
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产品关联
DOI
PubMed
高影响因子
JOURNAL OF APPLIED POLYMER SCIENCE
·
2017
·Vol. 134
·期 17
·
IF 1.86
Hui Zhang,Liting Yang,Yantao Li,Zijian Tang,Zhihuan Zheng,Li Zhang
In order to improve the flexibility properties of conventional epoxy resin, two novel soybean oil–based curing agents were synthesized. The curing agent obtained from the reaction between epoxy soybean oil and ethylene diamine was named EEDA, and another curing agent derived from epoxy soybean oil and isophorone diamine was named EIPDA. Several techniques were used to systematically investigate the effects of the structure and content of the two curing agents on the properties of the cured products. The Fourier transform infrared analysis demonstrated that epoxy resin reacted with soybean oil–based curing agents. The differential scanning calorimetry analysis showed that the curing process between diglycidyl ether of bisphenol-A (DGEBA) and soybean oil–based curing agents only had an exothermic peak. Thermogravimetric analysis indicated that the cured DGEBA/EIPDA system was more stable than the DGEBA/EEDA system below 300 °C. Mechanical tests and Shore D hardness tests suggested that excessive EEDA greatly enhanced the toughness of cured products because of the introduction of aliphatic chains.© 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017 , 134 , 44754.
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
HIGH PRESSURE RESEARCH
·
2020
·
IF 1.315
Xiaonan Wang,Qiang Tao,Yang Han,Qiuyang Hu,Jiaen Cheng,Hongsheng Jia,Pinwen Zhu
Obtaining both high hardness and toughness is a challenge in B4C-nano-adhesive composites. Solving the inhomogeneous distribution of nano-adhesives in B4C and forming the chemical bonding at grain boundary is an effective method. Here, we reported that the uniform distribution of titanium diboride (TiB2)-reinforced B4C composites synthesized by high-pressure and high temperature (HPHT). It is found that HPHT sintering can effectively inhibit the grain growth and increase the relative density. Moreover, HPHT sintering can cross high reaction energy barrier and effectively promote the formation of chemical bonding at grain boundary between B4C and TiB2. The optimal hardness and toughness value reach 30.0 ± 0.9 GPa and 7.87 MPa·m1/2, respectively. The improvement of hardness and toughness in the final products are ascribed to the strengthening of nanoTiB2 connection of B4C boundary and intergranular fracture mechanism. This work suggests a new way to achieve the uniform distribution of nanoTiB2 in B4C and form the chemical bonding at grain boundary, which is of great significance to the further development of TiB2-reinforced B4C composites with excellent mechanical properties.
研究领域:
材料科学
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机械工程
✓ 已验证
产品关联
DOI
高影响因子
Advanced Composites and Hybrid Materials
·
2022
·Vol. 5
·期 4
·3057-3067
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IF 11.806
Zhao Sipei,Li Shuiquan,Liu Huihui,Jiang Jin,Wang Meichen,Liu Haolang,Wang Weiwei,Wang Zhi
As a new thermosetting resin, polybenzoxazine has attracted extensive attention because of its excellent properties. However, the biggest challenge of polybenzoxazine is the balance among impact strength, thermal stability, and processability. In this work, we first introduced a 2-ureido-4[1H]-pyrimidone (UPy, containing quadruple hydrogen bonds) dimer into benzoxazine to tackle this challenge. In the blends containing 3 wt% UPy, its toughness and thermal properties have been simultaneously improved, while maintaining a high modulus and a negligible increasement in viscosity. The impact strength and the glass transition temperature ( T g ) reach 16.39 kJ·m −2 and 221 °C, which are 172% and 10 °C higher than that of polybenzoxazine, respectively. Meanwhile, this strategy was extended to carbon fiber surface modification to enhance the interfacial adhesion between fibers and resins. The mechanical properties of modified fiber composites are significantly improved. Furthermore, we firstly designed the cyclic flexural experiment of material and tried to propose an effective method to verify the effect of hydrogen bond dynamics on flexural properties of polybenzoxazine. Here, we not only provide a new way to get a balance among different properties of polybenzoxazine but also give a broad insight on the application of additional hydrogen bonds in thermoset resins. Graphical Abstract The improved comprehensive performances of polybenzoxazine were realized by introducing quadruple hydrogen bond motif.
研究领域:
材料科学
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化学工程
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产品关联
DOI
高影响因子
Materials
·
2023
·Vol. 16
·期 19
·6476
·
IF 3.4
Sijie Wang,Wen Chen,Xinyue Huang,Xuezheng Chen,De Li,Feng Yu,Yong Chen
As a kind of energy storage device, a flexible supercapacitor has the characteristics of high capacity, fast charge/discharge rate, good stability, portability and softness. Conductive polymer polypyrrole (PPy) can be used as an electrode material for supercapacitors due to its environmental friendliness, simple synthesis process, good conductivity and potential for large-scale production. However, pristine PPy inevitably suffers from structural rupture due to repeated doping/de-doping during charge and discharge processes, which in turn impairs its cycle stability. In general, compounding with flexible substrates like soft carbon materials, cellulose or nylon fabric, is a good strategy to weaken the inner stress and restrain the structure pulverization of PPy. Herein, cellulose is utilized as a soft substrate to compound with PPy based on the electrochemical oxidation of polypyrrole. The interfacial electrodeposition method can successfully obtain a smooth, uniform and flexible PPy/cellulose composite film, which shows good conductivity. The assembled symmetric supercapacitor with PPy/cellulose film has an optimized specific capacitance of 256.1 mF cm−2, even after 10,000 cycles at a current density of 1 mA cm−2. Furthermore, there is no significant capacitance loss even after 180° bending of the device. This work provides a new means to prepare flexible, low-cost, environmentally friendly and high-performance electrode materials for energy conversion and storage systems.Keywords:flexible surpercapacitor;polypyrrole;cellulose;flexibility
研究领域:
材料科学
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电化学
·
能源存储
✓ 已验证
产品关联
DOI
PubMed
高影响因子
危险品化学品经营许可证（带存储）