WEED SCIENCE
·
2020
·Vol. 68
·期 6
·565-574
·
IF 2.258
Li-Xia Zhao,Mao-Jun Jiang,Jia-Jun Hu,Yue-Li Zou,Shuang Gao,Ying Fu,Fei Ye
Protoporphyrinogen oxidase (PPO) is an important target for discovering new herbicides that interfere with the synthesis of porphyrin. To discover new PPO inhibitors with improved biological activity, a series of new diphenyl ethers containing tetrahydrophthalimide were designed and synthesized. Among them, J6.1 (IC50 = 4.7 nM) and J6.3 (IC50 = 30.0 nM) show higher maize (Zea mays L.) PPO inhibitory activity than the commercial herbicides oxyfluorfen (IC50 = 117.9 nM) and flumioxazin (IC50 = 157.1 nM). The greenhouse herbicidal activity of J6.3 is comparable to that of oxyfluorfen, and it is greater than that of flumioxazin. Even at a dose of 300 g ai ha−1, cotton (Gossypium hirsutum L.) and peanut (Arachis hypogaea L.) show greater tolerance to J6.3, suggesting that J6.3 could be used for further development of new herbicide candidates in those fields. In addition, molecular docking has been used to further study the mechanism of action of J6.3. The results show that the introduction of a nitro group and tetrahydrophthalimide into the diphenyl ether structure is beneficial to biological activity.
研究领域:
植物学
·
药理学
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产品关联
DOI
高影响因子
JOURNAL OF APPLIED POLYMER SCIENCE
·
2017
·Vol. 134
·期 36
·45281
·
IF 1.86
Yijian Wu,Hui Zhang,Baoqing Shentu,Zhixue Weng
This work aimed at studying the role of poly(phenylene oxide) (PPO) and polystyrene (PS) in toughening polyamide-6 (PA6)/styrene-ethylene-butadiene-styrene block copolymer grafted with maleic anhydride (SEBS- g -MA) blends. The effects of weight ratio and content of PPO/PS on the morphology and mechanical behaviors of PA6/SEBS- g -MA/(PPO/PS) blends were studied by scanning electron microscope and mechanical tests. Driving by the interfacial tension and the spreading coefficient, the “core–shell” particles formed by PPO/PS (core) and SEBS- g -MA (shell) played the key role in toughening the PA6 blends. As PS improved the distribution of the “core–shell” particles due to its low viscosity, and PPO guaranteed the entanglement density of the PPO/PS phase, the 3/1 weight ratio of PPO/PS supplied the blends optimal mechanical properties. Within certain range, the increased content of PPO/PS could supply more efficient toughening particles and bring better mechanical properties. Thus, by adjusting the weight ratio and content of PPO and PS, the PA6/SEBS- g -MA/(PPO/PS) blends with excellent impact strength, high tensile strength, and good heat deflection temperature were obtained. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017 , 134 , 45281.
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
Journal of Materials Chemistry B
·
2015
·Vol. 3
·期 20
·4259-4271
·
IF 4.726
Chunhuan Shi,Zhiqing Zhang,Fang Wang,Xiaoqing Ji,Zhongxi Zhao,Yuxia Luan
There are two major hurdles for the current anti-cancer drug delivery systems. One is the emergence of multidrug resistance (MDR) and the other is the conflict between long-circulation and cellular uptake. In the present study, the anticancer drug docetaxel (DTX) was successfully loaded into three series of micelles via self-assembly using a mixture of PEO–PPO–PCL and D-α-tocopheryl poly(ethylene glycol) 1000 succinate (TPGS), for the purpose of prolonging the blood circulation time as well as overcoming MDR of DTX. Three series of copolymers with different PCL molecular weights, PEO68–PPO34–PCL9, PEO68–PPO34–PCL18 and PEO68–PPO34–PCL36, were synthesized. The prepared spherical mixed micelles (MM) were found to possess nanoscale size (25–135 nm). The PEO–PPO–PCL/TPGS mixed micelles had a low critical micelle concentration (∼10−6 g mL−1) and a low hemolysis rate (<5%), which has proved that they are safe for use in vivo. Moreover, they had obvious sustained release behavior in vitro and a longer circulation time than free DTX in vivo. The P-gp inhibition assay, cellular uptake and MTT assay in cancer cells exhibited that DTX-loaded MM could overcome MDR, show higher cellular uptake and higher antitumor efficacy than free DTX. The IC50 values demonstrated that the three series of DTX-loaded MM were 69, 82 and 100 fold effective than free DTX after 72 h treatment with MCF-7 cells, respectively. Therefore, these results demonstrated that the prepared DTX-loaded MM provide desirable application in cancer chemotherapy.
研究领域:
药学
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肿瘤学
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生物材料
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产品关联
DOI
PubMed
高影响因子
Biomolecules
·
2019
·Vol. 9
·期 10
·514
·
IF 4.694
Li-Xia Zhao,Min-Lei Yin,Qing-Rui Wang,Yue-Li Zou,Tao Ren,Shuang Gao,Ying Fu,Fei Ye
The herbicide fomesafen has the advantages of low toxicity and high selectivity, and the target of this compound is protoporphyrinogen IX oxidase (PPO, EC 1.3.3.4). However, this herbicide has a long residual period and can have phytotoxic effects on succeeding crops. To protect maize from fomesafen, a series of thiazole phenoxypyridines were designed based on structure–activity relationships, active substructure combinations, and bioisosterism. Bioassays showed that thiazole phenoxypyridines could improve maize tolerance under fomesafen toxicity stress to varying degrees at a dose of 10 mg·kg−1. Compound4iexhibited the best effects. After being treated by compound4i, average recovery rates of growth index exceeded 72%, glutathione content markedly increased by 167% and glutathione S-transferase activity was almost 163% of fomesafen-treated group. More importantly, after being treated by compound4i, the activity of PPO, the main target enzyme of fomesafen, recovered to 93% of the control level. The molecular docking result exhibited that the compound4icould compete with fomesafen to bind with the herbicide target enzyme, which consequently attained the herbicide detoxification. The present work suggests that compound4icould be developed as a potential safener to protect maize from fomesafen.
研究领域:
植物保护
·
分子生物学
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DOI
高影响因子
JOURNAL OF THE ELECTROCHEMICAL SOCIETY
·
2021
·Vol. 168
·期 9
·094506
·
IF 4.316
Yiwen Nie,Junjie Chen,Zhihui Wu,Jinyue Zhou,Zhenghan Li,Shanjun Gao,Chunhui Shen
Aliphatic polymers, such as polypropylene, styrene ethylene butylene styrene and norbornene, which show great alkaline stability and flexibility, have become the main research trend of the skeleton of anion exchange membranes. Here, we prepared a copolymer with all carbon atoms on the main chain. Firstly, a new vinylimidazole cationic monomer was prepared, and then copolymerized with styrene and acrylonitrile to obtain a copolymer (PASIm). Furthermore, (2,6-dimethyl-1,4-phenylene oxide) (PPO) was introduced to cross-link with PSAIm to prepare AEMs with different crosslinking degrees (CEM-X, X = 6,12,18,24,30). 1H NMR and FT-IR showed that PASIm was successfully synthesized and crosslinked with PPO. The prepared membranes had high hydroxide ionic conductivity and excellent alkaline stability. AFM showed that the CEM-18 had obvious microphase separation structure, which was beneficial to the construction of ion channels in the membrane. Thus, the CEM-18 showed the highest ionic conductivity, up to 59.21 mS cm−1 at 80 °C. CEM-24 with higher crosslinking degree showed the highest alkaline stability. After immersing in 1 M KOH solution at 80 °C for 240 h, 86.52% of the initial ionic conductivity was retained. These results indicate that the prepared anion exchange membranes have broad application prospects.
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
COMPOSITES PART B-ENGINEERING
·
2019
·
IF 6.864
Jincheng Ran,Jiedong Qiu,Huali Xie,Xuejun Lai,Hongqiang Li,Xingrong Zeng
How to effectively enhance the flame retardancy of polyamide 46/polyphenylene oxide (PA46/PPO) alloy is one of the key issues needed to be addressed. In this work, organic-modified zirconium phosphate (OZrP) nanosheet was incorporated with PU-coated carbon fiber (CF) to flame-retard PA46/PPO alloy. The combination of OZrP and CF showed an outstanding combination effect in improving the flame retardancy and thermal stability of PA46/PPO. With the incorporation of 2 wt% OZrP and 20 wt% CF, the peak heat release rate and peak smoke production rate of PA46/PPO were reduced by 65.6% and 86.2%, respectively. Besides, the T i (temperature at 5% weight loss) and the residue of PA46/PPO/OZrP/CF were increased by 13.2 °C and 20.9 wt%, respectively, compared with PA46/PPO. The flame-retardant mechanism was further studied and revealed: when being burned, CF acted as the skeleton to improve the strength of char; simultaneously, OZrP catalyzed the carbonization of the polymer chains on the CF surface to form a strong and compact protective char layer, which blocked the transmission of heat and combustible gases, thus effectively improved the flame retardancy of the composite.
研究领域:
材料科学
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高分子化学
✓ 已验证
产品关联
DOI
高影响因子
ELECTROCHIMICA ACTA
·
2024
·
IF 5.5
Zhiyan Sui,Zhe Wang,Song Wang,Yan Wang
Appropriate addition of cation transport sites while maintaining the good mechanical properties of anion exchange membranes (AEMs) can effectively improve the hydroxide ion conductivity. Therefore, a series of poly (2,6-dimethyl-1,4-phenylene oxide) (PPO) based side-chain type AEMs containing dual conduction sites are successfully prepared. The 4-(4-dimethylaminostyryl)-1-methylpyridinium (DASP) side chains are grafted to brominated PPO at different ratios, which is confirmed by Fourier transform infrared spectroscopy (FT-IR). Analysis of the microscopic morphology reveals a distinct microscopic separation pattern of hydrophilic/hydrophobic regions, which provides efficient channels for the transport of hydroxide ions. The ionic conductivity of the PPO-DASP13 membrane reaches 89.97 mS/cm at 80 °C, which is benefited from the double cationic groups contained in the side chains, providing more conduction sites for hydroxide ions. Meanwhile, the tensile strength of membranes range from 17.83 MPa to 29.38 MPa, which have good mechanical properties. The ionic conductivity of all membranes retain about 70 % after a 800 h long-term alkali resistance test, which is related to the steric hindrance contained in the side chain structure and the conjugated system. Furthermore, the single cell based on PPO-DASP13 membrane with the highest ionic conductivity achieves a peak power density of 347.7 mW/cm 2 in H 2 -air (CO 2 -free) at 60 °C.
研究领域:
材料科学
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电化学
·
高分子化学
✓ 已验证
产品关联
DOI
高影响因子
Polymer Chemistry
·
2023
·Vol. 14
·期 16
·1933-1944
·
IF 4.6
Yi-Fang Lu,Song-Hai Wu,Cong Wang,Yong Liu,Fu-Gen Huang,Bao-Dong Song,Xu Han
Preparing low-molecular-weight poly(2,6-dimethyl-1,4-phenylene oxide) (LMW-PPO) with high thermal stability and satisfactory dielectric properties is a challenge. Herein, we reported two methods for synthesizing LMW-PPO using metal and non-metal catalysts. In the presence of Cu(II), PPO with an Mn of 6.0 × 103 can be obtained with peroxydisulfate (PDS) as the oxidant. In the absence of Cu(II) catalysts, mesoporphyrin IX dihydrochloride or methylamine can also catalyze PDS to produce low-molecular-weight and metal-free PPO (Mn of 4.9 × 103 or 4.6 × 103). PDS not only mediates the oxidation of Cu(I) to Cu(II) with Cu(II) catalysts, which is an important step for binding phenolates to form LMW-PPO, but also abstracts H from DMP to give DMP radicals, which then polymerize to LMW-PPO in the absence of the Cu(II) catalysts. In addition, PDS can effectively break the long-chain PPO to give shorter PPO, thus effectively mediating the molecular weight of PPO. Additionally, the decrease in Tg values from 215 °C to 159 °C with decreasing Mn of PPO mediated by peroxydisulfate indicate its improved processability while maintaining high thermal stability (Td5% = 427 °C–439 °C). The satisfactory dielectric properties of the PPO obtained using PDS and metal-free catalysts also imply its high potential to be used for insulating materials.
研究领域:
高分子化学
·
材料科学
✓ 已验证
产品关联
DOI
高影响因子
POLYMER
·
2019
·
IF 3.771
Chao Lv,Ruiyang Wang,Jia Gao,Ning Ding,Shunni Dong,Jingjing Nie,Junting Xu,Binyang Du
Enhanced phase separation and inverse order-to-order phase transition with increasing temperature was observed for a series of poly (acrylic acid)- b -poly (propylene oxide)- b -poly (acrylic acid) triblock copolymers with various block lengths by temperature-variable synchrotron small-angle X-ray scattering (SAXS). This abnormal phase behavior was attributed to the change of hydrogen (H)-bonding interaction in block copolymers upon increasing temperature and theoretically explained from thermodynamic viewpoint. The temperature-dependent FTIR analysis revealed that increasing temperature led to the weakening of overall H-bonding interactions and the increase of free C O and C–O–C groups. The Flory-Huggins interaction parameter χ of PAA and PPO blocks was positive and increased with increasing temperature as determined from the SAXS profiles of disordered block copolymer. The thermodynamic calculation indicated that the increase of Δ H was larger than the decrease of – T Δ S with increasing temperature because of the relatively large value of χ , leading to the increase of overall Δ G mix and hence the enhanced phase separation at higher temperature.
研究领域:
高分子科学
·
材料科学
·
热力学
·
物理化学
✓ 已验证
DOI
高影响因子
MACROMOLECULAR CHEMISTRY AND PHYSICS
·
2025
·
IF 2.7
Chenglong Wan,Like Hou,Qing Hu,Zihe Zhao,Yanxia Yang,Biao Zhao,Jianping Deng,Kai Pan
A series of thermoplastic polyamide elastomers (TPAEs) utilizing polyamide 66 (PA66) as the hard segment and amorphous diamine-sealed poly(oxypropylene)-poly(oxyethylene)-poly(oxypropylene) (PPO-PEO-PPO) with different molecular weight as the soft segment are synthesized through one-step melt polycondensation method. The chemical structure of TPAEs is confirmed by Fourier transform infrared spectroscopy (FT-IR) and hydrogen magnetic resonance spectroscopy ( 1 H-NMR). Differential scanning calorimetry (DSC) and dynamic mechanical analysis (DMA) results show that short-chain polyetheramine (Jeffamine-ED600) has good compatibility with PA66, which limits crystal growth and greatly reduced crystallinity, can be used as diluent to reduce the melting point of the material. However, the microphase separation of long-chain polyetheramine (Jeffamine-ED900) and PA66 leads to the increase of crystallinity, and the melting temperature does not decrease significantly with the increase of soft segment content. Mechanical properties tests show that all TPAEs exhibit good mechanical properties and excellent energy dissipation, with tensile strength up to 45 MPa and elongation at break up to 630%. The introduction of PEO unit results in the water absorption of TPAEs ranging from 25 to 65%, and the surface resistivity varying between 2.45 × 10⁹ and 1.6 × 10¹⁰ Ω, suggesting the synthesized TPAEs are suitable for use as permanent anti-static materials.
研究领域:
材料科学
·
高分子化学
✓ 已验证
产品关联
DOI
高影响因子
POLYMER COMPOSITES
·
2025
·
IF 4.7
Guangyu Zhu,Jinping Guo,Xi Lu,Yanxia Cao,Yanyu Yang,Jianfeng Wang,Wanjie Wang
Basalt fiber (BF) has been regarded as a promising reinforcement material for high-strength composites because of its good mechanical properties, thermal stability, and eco-friendliness. However, the inherent interfacial incompatibility between inorganic BF and organic polyphenylene ether (PPO) resin severely limits the properties of basalt fiber-reinforced polyphenylene ether (BF/PPO) composites. This work employs maleic anhydride-grafted polyphenylene ether (PPO-MAH) and carboxylated multi-walled carbon nanotubes (CNTs-COOH) as a dual-functional hybrid sizing to improve the interfacial interaction of BF/PPO composites based on synergistic chemical bonding and mechanical interlocking. Compared with the unmodified BF/PPO composite, the interlaminar shear strength, flexural strength, and tensile strength of modified BF/PPO composites increase by 64.0%, 39.8%, and 63.4%, respectively. Furthermore, these modified BF/PPO composites exhibit excellent flame retardancy and display rapid self-extinguishing behavior and no dripping due to CNT-induced carbonization and a dense char layer. These results provide a practical, eco-friendly, and efficient approach to simultaneously improve the interfacial adhesion, mechanical properties, and flame retardancy of BF/PPO composites and enlarge their applications for aerospace, automotive, and defense applications.
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF RADIOANALYTICAL AND NUCLEAR CHEMISTRY
·
2023
·Vol. 332
·期 4
·1047-1054
·
IF 1.6
Hu Yichen,Ma Jiaju,Liu Tonghuan,Zhang Yongjie,Yu Yuhong,Sun Zhiyu,Fang Fang,Dong Tianhao,Zhao Yanhong,Zhou Gen
In this paper, three polymeric bases (styrene, vinyl toluene, methyl methacrylate (MMA)) plastic scintillators were synthesized by thermal and UV irradiation polymerization. The influences of the concentrations of the primary fluorescent agent 2.5-diphenyloxazole (PPO) and wave-shift agent 1,4-bis-2(5-phenyloxazoyl)benzene (POPOP) on plastic scintillators characterization were investigated. The results suggest that the maximum emission wavelength of synthesized plastic scintillators with different polymeric base are all around 423 nm matching with maximum response wavelength of general photoelectric devices, and its decay time with several nanoseconds has reached the same level as the EJ-200. The maximum light yield of the plastic scintillator was achieved when the mass ratio of PPO/POPOP is 1.0%/0.02% for the styrene plastic scintillators.
研究领域:
材料科学
·
核技术
✓ 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）