REACTIVE & FUNCTIONAL POLYMERS
·
2022
·
IF 4.966
Yi Ning,Dian-sen Li,Lei Jiang
This work proposes a facile and solvent-free synthesis of a renewable toughening agent (EGFD) from eugenol , formaldehyde and polyetheramine through the Mannich reaction . EGFD was used to modify bismaleimide (BMI) monomer to synthesize toughened EGFD/BMI resin. Cured EGFD/BMI resin exhibited great toughness evidenced by its tensile elongation at break above 8%. Meanwhile, the cured EGFD/BMI resin showed unique deformation reversibility performance: the compressed resin samples could be quickly restored to its original state when heated at 100 °C for 10 min. In addition, cured EGFD/BMI resin displayed good thermostability with their highest 5% weight loss temperatures (T 5 ) and glass transition temperatures (T g ) of 333 and 122 °C. All the EGFD/BMI resin showed great film uniformity and good dielectric properties : their dielectric constants were from 3.20 to 3.78, and dielectric loss were from 0.0093 to 0.022.
研究领域:
材料科学
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化学工程
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高分子科学
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DOI
高影响因子
EUROPEAN JOURNAL OF NUCLEAR MEDICINE AND MOLECULAR IMAGING
·
2021
·Vol. 49
·期 3
·847-860
·
IF 9.236
Liu Jing-Jing,Wang Zun,Nie Li-Ming,Zhu Yuan-Yuan,Li Ge,Lin Lin-Ling,Chen Min,Zhang Guo-Jun
Purpose Obtaining tumour-free margins is critical for avoiding re-excision and reducing local recurrence following breast-conserving surgery; however, it remains challenging. Imaging-guided surgery provides precise detection of residual lesions and assists surgical resection. Herein, we described water-soluble melanin nanoparticles (MNPs) conjugated with cyclic Arg-Gly-Asp (cRGD) peptides for breast cancer photoacoustic imaging (PAI) and surgical navigation. Methods The cRGD-MNPs were synthesised and characterized for morphology, photoacoustic characteristics and stability. Tumour targeting and toxicity of cRGD-MNPs were determined by using either breast cancer cells, MDA-MB-231 tumour-bearing mice or the FVB/N-Tg (MMTV-PyVT) 634Mul/J mice model. PAI was used to locate the tumour and guide surgical resection in MDA-MB-231 tumour-bearing mice. Results The cRGD-MNPs exhibited excellent in vitro and in vivo tumour targeting with low toxicity. Intravenous administration of cRGD-MNPs to MDA-MB-231 tumour-bearing mice showed an approximately 2.1-fold enhancement in photoacoustic (PA) intensity at 2 h, and the ratio of the PA intensity at the tumour site to that in the surrounding normal tissue was 3.2 ± 0.1, which was higher than that using MNPs (1.7 ± 0.3). Similarly, the PA signal in the spontaneous breast cancer increased ~ 2.5-fold at 2 h post-injection of cRGD-MNPs in MMTV-PyVT transgenic mice. Preoperative PAI assessed tumour volume and offered three-dimensional (3D) reconstruction images for accurate surgical planning. Surgical resection following real-time PAI showed high consistency with histopathological analysis. Conclusion These results highlight that cRGD-MNP-mediated PAI provide a powerful tool for breast cancer imaging and precise tumour resection. cRGD-MNPs with fine PA properties have great potential for clinical translation.
研究领域:
医学影像
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癌症手术
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纳米技术
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生物医学工程
✓ 已验证
DOI
PubMed
高影响因子
FIRE SAFETY JOURNAL
·
2025
·
IF 3.3
Haoran Jiang,Yong Hu,Yong Jiang,Rong Qiu,Hui Huang
Due to the increased risk of phosphate depletion, there is an increasing demand for low-phosphorus or bio-based phosphorus flame inhibitors. Therefore, two novel composites with biologically-based phosphorus sources that chelate transition metal ions were synthesized via assembly method, i.e., Mn-PMC and Ni-PMC, the structure and binding states of the composites were examined by SEM, TEM, FTIR, XRD, XPS, BET and TGA. The results indicated that Mn-PMC and Ni-PMC (ⅰ) are nanoscale materials with well dispersed, (ⅱ) have an amorphous structure and have sites that bind to other substances, (ⅲ) contain no halogen elements. Then the combustion inhibition experiments of downward flame spread and TG-IR-MS analysis revealed (ⅰ) that the inhibition efficiency of the two prepared inhibitors was higher than that of commercial phosphate-containing inhibitor ADP. Among them, Ni-PMC had the best suppression effect, and the flame of cellulose sample containing it would automatically extinguish after igniting with a smallest dosage, (ⅱ) two inhibitors reduced the laminar flame velocity and flame temperature. (ⅲ) their flame suppression mechanism was indicated as that the pyrolysis releases inert gas to dilute the free radical concentration. This work is helpful for the development of efficient transition metal fire extinguishing agents to replace traditional phosphorus resources.
研究领域:
材料科学
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燃烧学
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环境科学
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF MATERIALS SCIENCE
·
2024
·Vol. 59
·期 18
·7779-7792
·
IF 3.5
Zhan Qingyan,Yang Po
Frontal ring-opening metathesis polymerization (FROMP) of dicyclopentadiene (DCPD) shows promise for manufacturing thermosets and composites. To widen the applications, this work develops a novel approach for the upgrading of polydicyclopentadiene (PDCPD) and fiber-reinforced composites via sequential FROMP and radical reactions to achieve high performance. Herein, we mixed DCPD, Grubbs catalyst and radical initiators in one pot, and initiated FROMP, a self-perpetuating reaction, to obtain FROMP-prepared PDCPD. Then, the further radical reactions were carried out at elevated temperature. With our strategy, the performances of PDCPD and its composites were dramatically upgraded. For instance, the T g of PDCPD could be significantly improved from ~171 °C to ~240 °C. The T g , flexural strength and modulus of FROMP fabricated composite were successively increased from 141 °C, 135.3 MPa and 36.9 GPa to 262 °C, 467.1 MPa and 43.2 GPa, respectively. We believe that this novel strategy will greatly improve the performance of PDCPD and composites, and open new avenues to apply FROMP to wider applications. Graphical Abstract
研究领域:
材料科学
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高分子化学
·
复合材料
✓ 已验证
产品关联
DOI
高影响因子
ACS Applied Polymer Materials
·
2022
·
IF 4.855
Yuan-Yuan Liu,Jian-Hua Cao,Ying Wang,Shao-Gang Shen,Wei-Hua Liang,Da-Yong Wu
In this study, we intend to solve the problem of the low glass transition temperature (Tg) and the high coefficient of thermal expansion (CTE) that colorless polyimide (PI) films always exhibit. First, we copolymerized 2,2′-bis(trifluoromethyl)-[1,1′-biphenyl]-4,4′-diamine (TFDB) with 4,4′-(hexafluoroisopropene) diphthalic anhydride (6FDA) and p-phthaloyl chloride (TPC) and obtained a series of transparent and colorless films (PAI-10). These PAI films showed a high Tg of 346–362 °C and a low CTE of 25.2–62.9 ppm/K, which were better than those of PI6FDA-TFDB. Subsequently, three rigid diamines, p-phenylenediamine (p-PDA), 5-amino-2-(4-aminophenyl)benzoxazole (DAPBO) and 5-amino-2-(4-aminophenyl)benzimidazole (DAPBI), were used to replace 10% of the TFDB (PAI-9P-5, PAI-9O-5, and PAI-9I-5, respectively) to investigate the effect of the rigid structure on the thermal and optical properties. The results showed that rigid structures can greatly improve the thermal properties but impair transparency to some extent. Among these, PAI-9O-5 possessed the best performance with T430 of 81.9%, Tg of 364 °C, and CTE of 19.8 ppm/K. Furthermore, we fabricated an organic light-emitting diode (OLED) with PAI-9O-5 as the substrate. The flexible and bendable OLED@PAI-9O-5 showed typical green emission at 520 nm, a turn-on voltage of 2.9 V, a luminance of 1000 cd/m2 at 5 V, a current efficiency (CE) of 2.53 cd/A, and an external quantum efficiency (EQE) of 0.81%, which were comparable to those of devices fabricated on conventional glass substrates.
研究领域:
材料科学
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高分子化学
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光电学
·
柔性电子学
✓ 已验证
产品关联
DOI
高影响因子
ACS Applied Materials & Interfaces
·
2024
·
IF 8.3
Ji Ma,Kaili Zhang,Lili Du,Xujie Wang,Zhijie Chen,Hao Chen,Changfeng Chen,Ping Qiu
Corrosion-resistant coatings with self-healing capabilities are still a great challenge for metal protection. In this study, a corrosion-resistant coating with intrinsic self-healing capabilities was developed by compounding hydroxy-terminated silicone oil (HTSO) with 2-ureido-4[1H]-pyrimidone (UPy) derivatives. The smooth surface of the coating was shown by scanning electron microscopy (SEM), and good smoothness was also exhibited in the cross-section, which indicated that the coating is very homogeneous from the top to the bottom. Thermogravimetric analysis (TG) was employed to illustrate the temperature-resistant characteristics of the coating, revealing its significant chemical stability up to 360 °C. The corrosion resistance of the coating is assessed through electrochemical impedance spectroscopy (EIS), the typical impedance at 0.01 Hz is 1.70 × 109 and 2.44 × 108 Ω·cm2 before and after exposure to a 3.5 wt % NaCl solution for 70 days. There was no significant change in the water contact angle of the coatings before and after immersion; however, the adhesion strength was reduced. Notably, the coating demonstrates immediate and multiple self-healing properties. The tensile stress of the associated healing sample experiences an augmentation within the temperature range of 30–120 °C, with the critical fracture strain of the healed sample reaching 235% at 120 °C. The self-healing mechanism of the coating is systematically investigated using in situ Raman spectroscopy.
研究领域:
材料科学
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化学工程
·
表面科学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
CARBOHYDRATE POLYMERS
·
2013
·
IF 3.479
Jie Chen,Cheng Peng,Jun Nie,John F. Kennedy,Guiping Ma
The hyaluronic acid (HA) fibers scaffold with an extracellular matrix mimic structure has been prepared via lyophilization. The morphology of the HA fibers varying the concentration from 0.05 wt% to 0.15 wt% was characterized by scanning electron microscope (SEM). The diameter of HA fibers increased and the morphology changed from fiber to sheet-like structure as the concentration of HA solution increased. To enhance the water-resistance, the pure HA fiber membranes were chemical cross-linked by 1-ethyl-3-(3-dimethylaminopropyl) carbodiimide hydrochloride (EDC), and confirmed by fourier transform infrared (FT-IR) spectra. In vitro degradation behavior of cross-linked HA fiber membranes in both of water and PBS solutions was investigated, the physical properties were also studied by differential scanning calorimetry (DSC) and thermogravimetry (TG). The results showed that the bonding water capacity increased after crosslinking, and indicated that the crosslinked HA fibers could be used as scaffold in tissue engineering.
研究领域:
材料科学
·
生物医学工程
·
组织工程
✓ 已验证
产品关联
DOI
PubMed
高影响因子
SCIENCE OF THE TOTAL ENVIRONMENT
·
2020
·
IF 6.551
Wenmei Tao,Wenyan Duan,Chunbo Liu,Dongdong Zhu,Xiaoxi Si,Ruizhi Zhu,Patryk Oleszczuk,Bo Pan
The presence of persistent free radicals (PFR) in biochars may greatly broaden the application of biochars in pollution control , but may also cause negative impacts to the environment. Understanding the structural basis and the formation mechanisms of PFR is essential for a targeted biochar production and application. This study used rice straw (RS), a ubiquitous agricultural waste , to investigate the generation processes of PFR in relation to RS pyrolysis kinetics. Based on a detailed thermogravimetric (TG) and derivative thermogravimetric (DTG) analysis, the activation energy was calculated by Kissinger-Akahira-Sunose (KAS) and Flynn-Wall-Ozawa (FWO) methods. This work combined pyrolysis kinetics analysis and solid particle characterization. Our results showed that lignin started to pyrolyze at a lower temperature than cellulose and hemicellulose. Lignin was the main factor for PFR generation. Chemical bond breaking contributed only slightly to PFR formation. The reconfiguration of the carbonaceous structures may be a more important contributor to PFR formation, while the cross-linking between different compositions and the interactions between the chemical compositions and inorganic minerals may play a significant role for PFR generation and stabilization in RS. This study provides useful theoretical basis to understand the thermal pyrolysis process of RS and the manipulation of biochar properties.
研究领域:
环境科学
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农业工程
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化学工程
·
材料科学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
INTERNATIONAL JOURNAL OF BIOLOGICAL MACROMOLECULES
·
2023
·
IF 8.2
Qing Yin,Jiali Liu,Zicheng Zhong,Yueyuan Zhang,Feiran Zhang,Mingming Wang
In this study, chitosan (CS) and phytic acid (PA) were employed as raw materials to synthesize a range of chitosan–phytic acid complexes (CP) with different ratios (CS:PA = 12:1, 9:1, 6:1, 3:1, 1:1). The structures and elemental compositions of the compounds were characterized using Fourier-Transform Infrared Spectroscopy (FT-IR) and Scanning Electron Microscopy with Energy-Dispersive X-ray Spectroscopy (SEM-EDS). The thermal stability of the synthesized materials was analyzed using a Thermogravimetric Analyzer (TG). Electrochemical testing was conducted to explore the corrosion inhibition effect of the modified inhibitors with varying ratios on Q235 steel in 3.5 wt% NaCl solution. Additionally, Scanning Electron Microscopy (SEM) was utilized to investigate the surface morphology of the immersed samples. When the CS:PA ratio was 3:1, CP exhibited an impressive corrosion inhibition efficiency of 94.9 %. Furthermore, the antimicrobial properties of CP were evaluated using the colony plate counting method. At a CS:PA ratio of 1:1, CP demonstrated the minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) at 0.1250 % and 0.5000 %, respectively. This research introduces a novel green corrosion inhibitor capable of simultaneously reducing the electrochemical corrosion of Q235 while inhibiting biocorrosion, avoiding the antagonistic effects arising from the simultaneous use of biocides and corrosion inhibitors in the system.
研究领域:
材料科学
·
腐蚀工程
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生物技术
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化工工程
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Catalysis Science & Technology
·
2023
·Vol. 13
·期 21
·6185-6197
·
IF 5
Hui Guo,Tingting Ge,Yuchao Li,Yuxia Li,Yanxia Zheng,Xinpeng Guo,Haofei Huang,Ming Wang,Cuncun Zuo
Organic solvent method was used to prepare the active component VPO, which was loaded on ball-milled γ-Al2O3 support. VPO/γ-Al2O3 catalysts were synthesized by in situ generation for the synthesis of acrylic acid (AA) by the aldol condensation of acetic acid (HAc) and formaldehyde (HCHO). The effects of the calcination temperature and the loading of the active component VPO on catalytic activity were systematically investigated. XRD, BET, SEM, CO2/NH3-TPD, FT-IR spectroscopy, and TG techniques were used to characterize the VPO/γ-Al2O3 catalysts. The results showed that the catalyst had the best crystal structure and acid–base activity center at a calcination temperature of 350 °C. The catalytic performance was evaluated using a fixed bed reactor. 60% VPO/γ-Al2O3 exhibited the highest reactivity, and the yield of AA was up to 51.5%. Response surface methodology (RAM) was used to optimize the reaction conditions for aldol condensation. The kinetic equation and reaction order of the aldol condensation reaction were determined using the VPO/γ-Al2O3 catalyst. It provides guidance for the in-depth study of aldol condensation reactions in the future.
研究领域:
催化
·
化学工程
·
材料科学
·
物理化学
✓ 已验证
产品关联
DOI
高影响因子
POLYMER DEGRADATION AND STABILITY
·
2022
·
IF 5.204
Xinming Ye,Yu Feng,Panpan Tian,Zhimao Li,Yingchun Li,Wensheng Wang,Jie Li,Liang Qiao,Kun Wang,Wenchao Zhang,Ye-Tang Pan,Rongjie Yang
Despite remarkable advances in developing flame retardants and smoke suppressants for epoxy resin (EP), engineering nitrogen-containing polyhedral oligomeric silsesquioxane (N-POSS) to impart superior fire safety properties to EP has remained an intractable challenge. In this work, two nitrogen-containing polyhedral oligomeric silsesquioxanes (N-POSSs), namely, aminoethyl-aminopropyl-hepta-phenyl polyhedral oligomeric silsesquioxane (AEAP-POSS) and aminopropyl-hepta-phenyl polyhedral oligomeric silsesquioxane (AP-POSS), were synthesized through the “corner-capping” reaction. The molecular structures of N-POSSs were fully characterized by FTIR, 1 H NMR, 29 Si NMR and MALDI-TOF MS, and the synthesized AEAP-POSS and AP-POSS were introduced into EP to solve the shortcomings of flammability. TGA results showed that the incorporation of 4 wt% N-POSS nanoparticles distinctly improved the char residue at 800 °C, which significantly enhanced the thermal stability of the EP composites. When 4 wt% of AP-POSS was introduced into EP, reductions in the peak of heat release rate (p-HRR), fire growth index (FGI), peak of smoke production rate (p-SPR), and the peak of CO production rate (p-COP) reached to 60.6%, 70.2%, 52.3% and 60.4%, respectively. Subsequently, TG-FTIR and XPS were utilized to investigate the flame retardancy and smoke suppression mechanism. Our work presented a considerable advancement for the facile fabrication of flame retardants based on nitrogen-containing polyhedral oligomeric silsesquioxane compounds.
研究领域:
材料科学
·
化学工程
·
高分子科学
·
消防安全工程
✓ 已验证
DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2021
·
IF 13.273
Kang Xue,Huaiyu Li,Lun Pan,Yiran Liu,Xiangwen Zhang,Ji-Jun Zou
With the continuous development of advanced fuel and engine technology, the boundary between liquid and solid fuel is more and more blurred, so the development of new solid-liquid two-phase fuels has become a major opportunity and challenge. Herein, two kinds of [email protected] energetic particles ( [email protected] and [email protected] ) were fabricated by an in-situ electrostatic self-assembly method. The thermal property, ignition and combustion performances of [email protected] are characterized by TG-DSC, CO 2 laser ignition and constant-volume combustion experiments. The results show that the initial exothermic temperature of [email protected] and [email protected] are reduced by about 60 and 110 °C, respectively, compared with nAl (579.6 °C). Moreover, [email protected] has a lower ignition delay time, higher peak pressure, and faster pressurization rate than nAl, especially [email protected] and [email protected] The combustion process of [email protected] is proposed, which can be obviously enhanced by regulating the interfacial reaction and the generation of microexplosions. In the ignition experiment of nanofluid fuel, [email protected] energetic particles exhibit the bifunction characteristics, which can simultaneously improve the ignition and combustion performances of solid-phase nAl particles and liquid-phase hydrocarbon fuel. This work provides a new strategy for advanced aerospace fuel by introducing MOF shells to construct bifunctional energetic particles with enhanced ignition and combustion properties.
研究领域:
材料科学
·
化学工程
·
航空航天工程
·
能源科学
✓ 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）