WATER RESEARCH
·
2024
·
IF 11.4
Rourou Zhang,An Ding,Xuejun Cai,Langming Bai,Guibai Li,Heng Liang,Chuyang Y. Tang
Widespread outbreaks of threatening infections caused by unknown pathogens and water transmission have spawned the development of adsorption methods for pathogen elimination. We proposed a biochar functionalization strategy involving ε-polylysine (PLL), a bio-macromolecular poly(amino acid)s with variable folding conformations, as a "pathogen gripper" on biochar. PLL was successfully bridged onto biochar via polydopamine (PDA) crosslinking. The extension of electropositive side chains within PLL enables the capture of both nanoscale viruses and micrometer-scale bacteria in water, achieving excellent removal performances. This functionalized biochar was tentatively incorporated into ultrafiltration (UF) system, to achieve effective and controllable adsorption and retention of pathogens, and to realize the transfer of pathogens from membrane surface/pore to biochar surface as well as flushing water. The biochar-amended UF systems presents complete retention (∼7 LRV) and hydraulic elution of pathogens into membrane flushing water. Improvements in removal of organics and anti-fouling capability were observed, indicating the broken trade-off in UF pathogen removal dependent on irreversible fouling. Chemical characterizations revealed adsorption mechanisms encompassing electrostatic/hydrophobic interactions, pore filling, electron transfer, chemical bonding and secondary structure transitions. Microscopic and mechanical analyses validated the mechanisms for rapid adsorption and pathogen lysis. Low-concentration alkaline solution for used biochar regeneration, facilitated the deprotonation and transformation of PLL side chain to folded structures (α-helix/β-sheet). Biochar regeneration process also promoted the effective detachment/inactivation of pathogens and protection of functional groups on biochar, corroborated by physicochemical inspection and molecular dynamics simulation. The foldability of poly(amino acid)s acting like dynamic arms, significantly contributed to pathogen capture/desorption/inactivation and biochar regeneration. This study also inspires future investigation for performances of UF systems amended by poly(amino acid)s-functionalized biochar under diverse pressure, temperature, reactive oxygen species of feeds and chemical cleaning solutions, with far-reaching implications for public health, environmental applications of biochar, and UF process improvement.
研究领域:
环境工程
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水处理
·
材料科学
·
生物技术
·
公共卫生
✓ 已验证
产品关联
DOI
PubMed
高影响因子
JOURNAL OF NANOPARTICLE RESEARCH
·
2021
·Vol. 23
·期 1
·1-12
·
IF 2.253
Zhang Gongguo,Liu Zhiang,Fu Xiaowei,Zhao Wenjun,Yin Xunxiao,Niu Xiankang,Kong Rongmei,Qu Fengli,Zheng Yiqun
Branched Au nanocrystals with sub-10-nm arms are synthesized via a one-pot reduction in aqueous phase. The success of current work relies on the use of octadecyltrimethylammonium chloride as the shape-directing capping agent to facilitate the formation of branched products in high purity. Their overall size could be controlled in the range of 16–60 nm by varying the Au precursor amount or concentration of capping agent, and the diameter of arms is limited to sub-10-nm size range. Interestingly, Au nanocrystals with a unique morphology, sheet-wrapped dendrites, could be obtained when the concentration of a reductant was varied. The current strategy is also validated effective in the fabrication of dendritic products composed of other noble metals or alloys in addition to Au by simply using the alternative metal precursor. As compared to spherical counterparts, the current branched Au nanocrystals exhibited noticeable red-shift in UV-Vis extinction spectrum and enhanced catalytic activities for electrooxidation of ethanol in alkaline media. Graphical abstract
研究领域:
材料科学
·
化学
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产品关联
DOI
高影响因子
JOURNAL OF APPLIED POLYMER SCIENCE
·
2016
·Vol. 134
·期 2
·
IF 1.866
Weitao Ye,Wei Wei,Xiaoma Fei,Rongjie Lu,Na Liu,Jing Luo,Ye Zhu,Xiaoya Liu
A six-arm star-shaped poly( ε -caprolactone) (s-PCL) based on cyclophosphazene core was obtained by presynthesis of a hydroxy-teminated cyclophosphazene derivative and subsequent initiation of the ring-opening polymerization of ε -caprolactone, and its use in different proportions as toughening modifier of diglycidylether of bisphenol A/anhydride thermosets was studied. The star-shaped polymer was characterized to have approximately 30 caprolactone units per arm. Differential scanning calorimetry revealed a nonsignificant influence on the curing process of the epoxy-anhydride formulation by the addition of s-PCL. The s-PCL-modified epoxy thermosets exhibited a great improvement in both toughness and strength compared with the neat resin, as the result of a joint effort by the internal rigid core and the external ductile polyester chains of s-PCL. When the addition of the modifier was 3 wt %, an optimal mechanical and thermomechanical performance was achieved. The impact resistance and tensile strength of the cured epoxy resin were enhanced by 150% and 30%, respectively. The glass transition temperature was also increased slightly. Moreover, the addition of the star-shaped modifier had little harmful effect on the thermal stability of the material. Thus s-PCL was proved to be a superior toughening agent without sacrificing thermal and mechanical properties of the thermosets. © 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017 , 134 , 44384.
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
COLLOIDS AND SURFACES A-PHYSICOCHEMICAL AND ENGINEERING ASPECTS
·
2017
·
IF 2.714
Xiao-Hui Dai,Wei-He Yang,Wen-Li Yan,Jia-Ming Hu,Yi-Rong Dai,Jian-Ming Pan,Yong-Sheng Yan
Different generations of porphyrin-cored dendrimers consisting of novel siloxane- poly(amido amine) dendron-like arms have been synthesized via copper(I)-catalyzed Huisgen 1,3-dipolar cycloaddition reaction of azide-modified 5,10,15,20-tetrakis(4-hydroxyphenyl)-porphyrin with different generations of propargyl focal point novel siloxane-poly(amido amine) typed dendron (Si-PAMAM). The used different generations of Si-PAMAM were obtained by the “arm-first” strategy based on the Michael addition reaction and Amidation reaction, orderly. The structure of porphyrin dendrimers is established by 1 H NMR, 13 C NMR, MALDI-TOF-MS and FT-IR analysis. PP-Si-PAMAM-Dm (m = 1, 2, and 3), not only gave strong fluorescence emission and the intensity increased significantly as the generation growing, but also showed a remarkable pH-responsive in fluorescence emission. These interesting properties indicate that synthesized porphyrin dendrimers may be able to act as pH-responsive probes suitable for biomedical imaging, diagnosis and treatment.
研究领域:
有机化学
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材料科学
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生物医学工程
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产品关联
DOI
高影响因子
Polymer Chemistry
·
2012
·Vol. 4
·期 4
·1107-1114
·
IF 5.321
Haiyang Gao,Ying Tang,Zhilong Hu,Qirui Guan,Xinbo Shi,Fangming Zhu,Qing Wu
A tandem synthetic strategy combining chain walking polymerization and azide–alkyne click chemistry was successfully used to prepare amphiphilic copolymers with a dendritic polyethylene core and poly(ethylene oxide) (PEO) arms. Dendritic polyethylene (DPE) tethered with multi-reactive hydroxyl groups (DPE-(OH)11) was synthesized by copolymerization of ethylene and trimethylsilyl-protected 2-hydroxyethyl acrylate using an α-diimine palladium catalyst under low ethylene pressure of 0.1 atm. Alkynyl-terminated DPE (DPE-()11) was quantitatively obtained by esterification reaction of DPE-(OH)11 with pentynoic acid. Using a “grafting to” technique, PEO precursors with a terminated azido group were introduced to the DPE core with high efficiency by azide–alkyne click coupling reaction. The self-assembly behaviors of the obtained core–shell amphiphiles in selective solvents including water and hexane were studied by TEM, AFM and fluorescence. Supramolecular vesicles, unimolecular micelles, and multi-molecular micelles were observed, which is dependent on selective solvent as well as number and chain length of PEO arm.
研究领域:
材料科学
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高分子化学
✓ 已验证
DOI
高影响因子
Catalysis Science & Technology
·
2022
·Vol. 12
·期 22
·6687-6703
·
IF 6.177
Furong Cao,Yun Wang,Xing Wang,Wenjuan Zhang,Gregory A. Solan,Rui Wang,Yanping Ma,Xiang Hao,Wen-Hua Sun
Five types of N-(2-(diphenylphosphino)ethyl)-2-R-5,6,7,8-tetrahydroquinolin-8-amines (R = H L1, Me L2, iPr L3, Cl L4, Ph L5) along with one example of an N-isopropyl-5,6,7,8-tetrahydroquinolin-8-amine (L6) have been prepared and employed as neutral ligand supports for zinc(II) chloride complexes, LZnCl2 (Zn1–Zn6). All zinc compounds were characterized by multinuclear NMR spectroscopy (1H/13C/31P) and elemental analysis, while the structures of Zn2 and Zn5 were further studied by single crystal X-ray diffraction: distorted tetrahedral geometries with the diphenylphosphine moieties non-coordinated were a feature. Pre-treatment of Zn1–Zn5 with two equivalents of either LiCH2SiMe3 or LiN(SiMe3)2 led to catalysts displaying good to exceptionally high activity for the ring opening polymerization (ROP) of ε-caprolactone (ε-CL) at 50 °C. For example, Zn4/2LiCH2SiMe3 displayed a TOF of 2.1 × 104 h−1 with 71% conversion seen within 10 minutes with the ε-CL : Zn molar ratio at 5000 : 1; the resulting polycaprolactone (PCL) comprised predominately cyclic structures along with lower levels of trimethylsilylmethyl-capped linear PCL. By comparison, Zn1–Zn5 on treatment with two equivalents of LiN(SiMe3)2 at the same high monomer to zinc ratio, led to catalysts exhibiting an order of magnitude higher activity. Zn1/2LiN(SiMe3)2 in the presence of BnOH exhibited a remarkable TOF of 1.35 × 105 h−1 with 90% monomer conversion within two minutes. In these cases, a distinct selectivity towards linear polymers capped with CH3O end-groups (derived from the quenching solvent) was observed with cyclic polyesters only observable with larger amounts of ε-CL. As a general observation, the 2-R substituent on the chelating ligand showed noticeable effects on the efficiency and on the molecular weight of the PCLs, with 2-Cl-containing Zn4 in combination with LiCH2SiMe3 and BnOH affording the highest molecular weight PCL of the study (9.57 × 104 g mol−1). Based on the microstructural properties of the PCL, distinct mechanisms (viz., coordination–insertion and ring expansion) have been proposed to account for the mode of propagation mediated by Zn/2LiCH2SiMe3 and Zn/2LiN(SiMe3)2. In addition, a zinc silylamido L1−HZn[N(SiMe3)2] (Zn7) species has been tentatively assigned (obtained via deprotonation of L1 with Zn[N(SiMe3)2]2), that proved inactive for the ROP of ε-CL but displayed good activity for ROP of rac-LA.
研究领域:
有机化学
·
高分子化学
·
材料科学
✓ 已验证
DOI
高影响因子
LANGMUIR
·
2020
·
IF 3.557
Shaoqiao Li,Zhuliu Xiao,Kairui Guo,Huihui Gan,Jirong Wang,Yong Zhang,Liping Yu,Zhigang Xue
Porous membranes fabricated from poly(vinylidene fluoride) (PVDF) and a star polymer with linear poly(ethylene glycol) (PEG) arms and cycloPEG cores were fabricated via the phase-separation method. The porous gel polymer electrolytes (PGPEs) were obtained by immersing the porous membranes in the electrolyte solution. When the additive amount of star polymer was up to 20 wt %, the prepared membrane had the largest porosity and the pores were uniformly distributed in the membrane. The star polymer can not only decrease the crystallization of PVDF and enhance the absorption of liquid electrolyte but also offer ion conduction channels (cycloPEG cores). Therefore, the PGPE with 20 wt % star polymers exhibited competitive ionic conductivities of 1.27 mS cm–1 at 30 °C and 2.89 mS cm–1 at 80 °C. To stabilize the liquid electrolyte in the holes of porous membranes, a gelator was introduced in the liquid electrolyte to form gelled porous gel polymer electrolytes (GPGPEs), and the leakage of liquid electrolytes was thus remarkably reduced. The ionic conductivity of GPGPEs with 20 wt % star polymer and 1.5 wt % gelator was importantly improved at high temperatures (6.02 mS cm–1 at 80 °C). We systematically investigated the electrochemical performances of PGPEs without star polymer, PGPEs with star polymer, and GPGPEs with star polymer. The incorporation of star polymers with linear PEG arms and cycloPEG cores into the PGPEs and GPGPEs significantly improved the electrochemical performances of the lithium metal/LiFePO4 cell assembled with the PGPEs or GPGPEs.
研究领域:
材料科学
·
电化学
·
储能技术
✓ 已验证
DOI
PubMed
高影响因子
Polymer Chemistry
·
2015
·Vol. 6
·期 12
·2192-2203
·
IF 5.52
Yun Zhang,Maohua Chen,Xiaoming Luo,Hong Zhang,Chaoyu Liu,Huiyan Li,Xiaohong Li
Micelle behaviors have been studied intensively for linear block copolymers, and amphiphilic polymers with a non-linear architecture, including star polymers, dendrimers, and hyperbranched polymers are showing advantages in the loading of anticancer drugs. In the current study, multiarmed amphiphilic copolymers with drug conjugates were developed for the construction of micelles to alleviate premature drug release during circulation and to achieve glutathione (GSH)-mediated intracellular drug delivery. Folic acid (FA) was grafted on some of the arms of 4-armed poly(ethylene glycol) (4-arm-PEG) as the targeting groups of micelles, and ε-caprolactone (ε-CL) was copolymerized with PEG from the rest of the arms, followed by camptothecin (CPT) conjugation through dithiodipropionic acid. The effect of the number of arms used for FA conjugation and the length of PCL blocks on micelle properties, reductive sensitivity, cellular uptake, and antitumor activities were evaluated. The amphiphilic copolymers with star-shaped miktoarms were self-assembled into micelles with an average size of around 100 nm and critical micelle concentrations (CMCs) as low as 0.8 μg mL−1. The distribution of hydrophobic PCL segments in more arms resulted in micelles with lower CMCs, higher structural stability, and greater sensitivity of CPT release in the presence of GSH. But, the conjugation of FA on fewer arms led to lower FA densities and less efficient cellular uptake of the micelles. In view of the performance of cellular uptake, CPT loading, and reduction-sensitive release, micelles from 4-armed copolymers with FA conjugation on two arms and PCL copolymerization on another two arms resulted in the most significant antitumor activities. It is suggested that the composition and arm structure of amphiphilic copolymers with star-shaped miktoarms show significant effects on micelle behavior, and optimal antitumor activities can be achieved through judicious selection of multiple arms for conjugating targeting groups and chemotherapeutic drugs.
研究领域:
药学
·
聚合物化学
·
癌症研究
·
药物递送系统
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF MEMBRANE SCIENCE
·
2019
·
IF 7.015
Haicheng Jiang,Qi Zhao,Panpan Wang,Jun Ma,Xuedong Zhai
Fabricating high-flux, low-fouling gravity-driven membranes (GDM) has proved to be an extremely challenging work. In this study, a novel tailored amphiphilic multi-arms polymer poly(propylene glycol)-silane-poly(ethylene glycol) (PPG-Si-PEG) was synthesized and blended into Polyvinylidene Fluoride (PVDF) matrix to fabricate GDM via nonsolvent induced phase separation method. The incorporation of multi-arms polymers affected phase separation and surface segregation behaviors, resulting in the formation of more porous structure, which were demonstrated by scanning electron microscopy (SEM). Moreover, the hydrophilic PEG arms in polymers were enriched onto membrane surface through surface segregation and utilized to improve the hydrophilicity of membranes, which were confirmed by Fourier transform infrared (FTIR), X-ray photoelectron spectroscopy (XPS) and contact angle measurement. The separation and antifouling properties of the membranes were evaluated by using gravity as the driving force, employing bovine serum albumin (BSA) as the model foulant. The water flux of membranes increased from 4.6 L m −2 h −1 for the control membrane to 12.1 L m −2 h −1 for PVDF/PPG-Si-PEG∼5% membrane. The antifouling properties of modified membranes were effectively improved in comparison with that of control membrane. The flux recovery ratio, especially for PVDF/PPG-Si-PEG∼5% membrane, was up to 99.4%. This study provided a new method for antifouling modification of GDM.
研究领域:
材料科学
·
环境工程
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF CATALYSIS
·
2025
·
IF 6.5
Shan Wu,Jian Shi,Qian Duan,Ludan Shang,Xiaodong Zhang,Yuhan Duan
Porphyrins and phthalocyanines are considered as visible light catalysts with great development potential due to their unique π-conjugated structure, strong visible light absorption and structural tunability. However, they are easy to aggregate and difficult to dissolve, and their application in the field of photocatalysis is limited. Based on the above problems, in this study, three four-arms star-shaped thermosensitive copolymers (PcZn-(PNIPAM n -co-PUMPP m ) 4 ) photocatalysts with zinc phthalocyanine as the core and porphyrin thermosensitive copolymer as the arms was constructed by using RAFT polymerization technology and the ’core first’ route. The visible light catalytic activity of the prepared star-shaped copolymers was evaluated by using 1,5-dihydroxynaphthalene (DHN) and methylene blue (MB) as model pollutants. The three copolymers were found to be effective in oxidizing DHN to juglone and degrading MB. Among them, PcZn-(PNIPAM 33.5 -co-PUMPP 1.6 ) 4 (P3) showed the highest DHN conversion efficiency (100.0 %), reaction yield (70.0 %) and MB degradation (96.9 %). 1 O 2 and O 2 · - are the main active substances in the visible photocatalytic process. Based on UV–vis absorption spectra, Fluorescence spectra, EIS Nyquist plots and transient photocurrents, it is confirmed that P3 has a wider range of visible light absorption, and there is effective energy and electron transfer between TTPcZn and UMPP units in P3, which makes it have higher catalytic activity. More importantly, the lower critical solution temperature (32.6 ∼ 32.9 °C) of P3 makes it possible to achieve homogeneous catalysis and heterogeneous recovery through simple temperature regulation in the catalytic process, which makes P3 have good reusability. This work paves a way for the construction of high-performance and recyclable visible polymer photocatalyst.
研究领域:
材料科学
·
环境科学
·
化学工程
✓ 已验证
产品关联
DOI
高影响因子
POLYMER
·
2015
·
IF 3.562
Huanhuan Liu,Xiao Jiang,Rongjian Bian,Min Tong,Dandan Tang,Xiangdong Zhou,Youliang Zhao
Controlled synthesis of A 2m B 2n -type (m ≈ n ≈ 8) starlike copolymers comprising an oligomeric poly(styrene- co -maleimide) core and two types of V-shaped arms individually generated by ATRP and ROP was described. Multistep syntheses involving RAFT copolymerization , end group removal, ATRP of vinyl monomers such as styrene (St), methoxyethyl methacrylate (MEMA) and tert -butyl acrylate ( t BA), and ROP of ε -caprolactone (CL) were used to construct the target miktoarm stars with controlled molecular weight and relatively low polydispersity (PDI = 1.07–1.22). The resultant star copolymers had high bromide functionality and uniform chain length of ATRP-generated arms, evident from chain extension polymerization and cleavage of arms. Meanwhile, a pH-responsive (PAA) 2m (PCL) 2n star was also obtained by selective hydrolysis. The synthetic strategy via combination of RAFT copolymerization and “core first” approach is versatile in constructing various A 2m B 2n stars, and this study further paves way for facile synthesis and properties of new types of miktoarm stars.
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
CRYSTENGCOMM
·
2023
·Vol. 25
·期 8
·1232-1239
·
IF 3.1
Gui-Mei Huang,Shuang Li,Meng-Xia Ma,Shi-Ming Li,Wen-Qiang Li,Qing-Ling Ni,Liu-Cheng Gui,Xiu-Jian Wang
Four MOFs with mixed ligands, [Zn3(3-BABA)2(bpa)2(H2O)2]n (1), [Cd3(3-BABA)2(bpa)2]n (2), [Cd3(3-BABA)2(bpe)2]n (3), and {[Cd3(3-BABA)2(bib)(DMA)2]·H2O}n (4) (where 3-H3BABA = 4′,4′′′-(((2-carboxyphenyl)azanediyl)bis(methylene))bis(([1,1′-biphenyl]-2-carboxylic acid)), bpa = 4,4′-azopyridine, bpe = 1,2-bis(pyridin-4-yl)ethane, and bib = 1,4-bis(imidazole)butane), have been synthesized. They are characterized by single crystal X-ray diffraction, X-ray powder diffraction (XRPD), thermogravimetric analysis (TGA) and Fourier transform infrared (FT-IR) spectroscopy. In 1, two 3-BABA and two bpa bridge three Zn2+ ions to form a bicyclic [Zn3(3-BABA)2(bpa)2] unit which is further bridged by carboxylate groups with its adjacent units, resulting in a one-dimensional chain. In 2, 3 and 4, the [Cd3(CO2)6] units are bridged by six 3-BABA ligands into a three-dimensional structure. However, the adjacent [Cd3(CO2)6] units in 2 and 3 are doubly-bridged simultaneously by corresponding pyridyl ligands, while the adjacent [Cd3(CO2)6] units in 4 are singly-bridged simultaneously by corresponding pyridyl ligands. The luminescence sensing investigation indicates that compound 1 exhibits extremely sensitive and selective detection of Cu2+ with a detection limit of 0.363 μM, and compounds 2–4 show extremely sensitive and selective detection of Fe3+ with detection limits of 0.539 μM, 0.265 μM, and 0.748 μM, respectively. Competitive experiments in the presence of interfering cations with 1–4 revealed no major change in the quenching efficiency.
研究领域:
化学
·
材料科学
✓ 已验证
DOI
高影响因子
危险品化学品经营许可证（带存储）