Polymer Chemistry
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2012
·Vol. 3
·期 12
·3330-3339
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IF 5.321
Cheng-guang Mu,Xiao-dong Fan,Wei Tian,Yang Bai,Zhen Yang,Wei-wei Fan,Heng Chen
We describe the synthesis and self-assembly of a well-defined H-shaped terpolymer in this paper. A block copolymer of poly(ethylene glycol) (PEG) and poly(N,N-dimethylaminoethyl methacrylate) (PDMA), which bears an azido group at the diblock junction (PEG–N3(–PDMA)) was first prepared by atom transfer radical polymerization. Then, an alkynyl-terminated narrow distributed polytetrahydrofuran (PTHF-Alk) was synthesized as another building block via cationic ring opening polymerization. The well-defined H-shaped terpolymer was afforded by clicking PEG–N3(–PDMA) onto both chain-ends of PTHF-Alk. This H-shaped terpolymer can self-assemble into micelles with different sizes and morphologies at various solution pH values. The micellar size also exhibits temperature-dependence at pH 7.4 and 9.2. The variation of size and morphology of the micelles with the solution pH and temperature is ascribed to the pH- and thermo-responsive properties of the PDMA block.
研究领域:
高分子化学
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材料科学
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高影响因子
JOURNAL OF POLYMER SCIENCE PART A-POLYMER CHEMISTRY
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2015
·Vol. 54
·期 8
·1056-1064
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IF 3.113
Wenjuan Wang,Ling Lin,Jiang Lu,Hui Liang,Hao Feng,Lifen Hu
Triblock copolymers (MPEG- b -PCEMA- b -PHQHEMA) bearing cinnamoyl and 8-hydroxyquinoline side groups with different block length are synthesized by a two-step reversible addition fragmentation chain transfer polymerization of cinnamoyl ethyl methacrylate (CEMA) and 2-((8-hydroxyquinolin-5-yl)methoxy)ethyl methacrylate (HQHEMA), respectively. The self-assembly of MPEG- b -PCEMA- b -PHQHEMA in mixture of THF and ethanol is investigated by varying the ratio of THF and ethanol. Spheric micelles with diameter of 63.7 nm and polydispersity of 0.128 are obtained for MPEG 113 - b -PCEMA 15 - b -PHQHEMA 17 in THF/ethanol with a volume ratio (v/v) of 5/5. The PCEMA inner shell of the resulted micelles is photo-crosslinked under UV radiation to give stabilized micelles. The complex reaction of the stabilized micelles with Zn(II) is investigated under different conditions to give zinc(II)-bis(8-hydroxyquinoline)(Znq 2 )-containing micelles. When the complex reaction is carried out in THF/ethanol (v/v = 5/5) or THF/toluene (v/v = 6/4) with zinc acetate, fluorescent Znq 2 -containing micelles are obtained without obvious change in diameters and morphologies. The fluorescent micelles exhibit green emission with λ max at 520 nm. © 2015 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2016 , 54 , 1056–1064
研究领域:
材料科学
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高分子化学
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DOI
高影响因子
JOURNAL OF POWER SOURCES
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2017
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IF 6.395
Chen Xiao Lin,Xiu Qin Wang,Ling Li,Fang Hua Liu,Qiu Gen Zhang,Ai Mei Zhu,Qing Lin Liu
To explore highly conductive and alkaline stable anion exchange membrane (AEM) materials, triblock copolymers bearing alkyl-tethered cycloaliphatic quaternary ammonium-head-groups are prepared via nucleophilic substitution , Friedel-Crafts acylation, ketone reduction and Menshutkin reaction . The designed triblock copolymers composed of quaternized poly(phenylene oxide) segments and poly(ether sulfone) segments are responsible for the microphase separated morphology and well-connected ion domains, as confirmed by transmission electron microscopy . The highest conductivity, up to 105.1 mS cm −1 at 80 °C is achieved for the AEM with ionic exchange capacity (IEC) of 1.81 meq g −1 . Furthermore, the AEMs show robust alkaline stability due to the alkyl-tethered cation-head-groups structure. High retention of hydroxide conductivity (88.9%) and IEC (91.2%) is observed for the AEMs via degradation test in a 1 M aqueous KOH solution at 80 °C for 480 h. Based on the AEM with high conductivity, a H 2 /O 2 fuel cell achieves a peak power density of 176.5 mW cm −2 (80 °C) at a current density of 500 mA cm −2 .
研究领域:
材料科学
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燃料电池技术
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高影响因子
CHINESE JOURNAL OF CHEMISTRY
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2015
·Vol. 33
·期 12
·1338-1346
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IF 1.578
Yupeng Wu,Yangchun Tao,Kuan Cai,Siwei Liu,Yi Zhang,Zhenguo Chi,Jiarui Xu,Yen Wei
Two triblock polymers, tetraaniline- block -poly( N -isopropyl acrylamide)- block -poly(hydroxyethyl acrylate) (TA- b -PNIPAM- b -PHEA) and TA- b -PHEA- b -PNIPAM, were synthesized with unambiguous structure by a two step method. The difference of these two diblock polymers is the connection order of carboxyl group to block, e.g ., carboxyl group to PNIPAM block for PNIPAM- b -PHEA and to PHEA block for PHEA- b -PNIPAM. Secondly, block tetraaniline was linked to the diblock polymer through amidation to yield the corresponding triblock copolymer. Both of them have almost the identical chemical compositions. The only difference is the connection order of each block in the triblock polymers. When they were self-assembled at 45°C in a suitable solution, both of their aggregates have spherical shape with slight defects on their surface with the average diameter of about 400 nm. However, when their aggregate dispersion was cooled down to 20°C, only TA- b -PHEA- b -PNIPAM's morphology changed, forming worm-like aggregates with the diameter of about 100–200 nm transformed from spherical aggregates. Both amphiphilic property and position of each block in this triblock copolymer are very essential for this morphology transformation. Since the worm-like aggregates presented here by our group have hollow structure inside, its controlled release properties for doxorubicin were evaluated. Drug release experiment indicated that along with the temperature changes, the rearrangement of the intermediate layer structure caused morphology change in aggregate, thus accelerating the speed of drug release.
研究领域:
材料科学
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生物医学工程
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高分子化学
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DOI
高影响因子
JOURNAL OF CHROMATOGRAPHY A
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2021
·
IF 4.759
Ruijuan Duan,Meiling Qi
This work presents the investigation of using the amphiphilic triblock copolymer composed of poly(ethylene oxide)(PEO)-poly(propylene oxide) (PPO)-poly(ethylene oxide) (PEO) (denoted as EPE) as the stationary phase for gas chromatographic (GC) analyses . The EPE capillary column exhibited moderate polarity and column efficiency of 4348 plates/m determined by naphthalene at 120 °C ( k = 11.52) . Different from the PEG and polysiloxane homopolymers, it showed high-resolution performance towards a wide range of aliphatic and aromatic isomers in terms of polarity and acid-base properties. Particularly, the EPE column displayed distinct advantages for separating the critical isomers of alkanes, anilines and phenols and the components of the lemon essential oil over the commercial PEG and polysiloxane columns. In addition, the EPE column exhibited excellent separation repeatability and reproducibility with the relative standard deviation (RSD) values in the range of 0.03% – 0.08% for run-to-run, 0.14% – 0.61% for day-to-day and 3.1% – 4.0% for column-to-column, respectively. Moreover, the EPE column was investigated in terms of thermal stability, the minimum allowable operating temperature (MiAOT) and sample loadability. Its application to GC-MS analysis of the essential oil demonstrated its feasibility for practical analyses. This work demonstrates the promising future of triblock copolymers as a new class of selective stationary phases for GC analyses, which is barely reported up to date. The findings of this work is of important value for fundamental researches and practical applications.
研究领域:
分析化学
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材料科学
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DOI
PubMed
高影响因子
CHEMICAL ENGINEERING JOURNAL
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2021
·
IF 13.273
Ming Zhu,Tao Yang,Liting Wang,Mengyuan Xiong,Wenjun He,Yaowei Chen,Weili Deng,Xiaoyan Li
Stretchable electronics have attracted great interest due to their mechanical flexibility similar to tissues. In this paper, a superstretchable fiber membrane is designed based on step by step assembly of electrospun poly(styrene-ethylene/butylene-styrene) (SEBS), carbon nanotubes (CNTs) and electropolymerized polyaniline (PANi). The prepared soft membrane has a hierarchical micro-nano structure, forms a good interface with the triblock copolymer fiber, and shows good electromechanical performance. The electrical conductivity of the membrane is about 2.40 S·cm −1 , the tensile strength and the maximum tensile strain can reach 8.2 MPa and 1200% respectively, while the Young’s modulus is only about 0.26 MPa. The conductivity of the prepared membrane remains stable after 1000 cycles, and the fractured composite membrane can be healed by hot pressing. In addition, this stretchable composite membrane has been successfully demonstrated to detect various human motions, and can even work underwater. Our results provide a simple and controllable method to achieve the stable soft stretchable electronics with large strain, and demonstrate promising potential in the expanded application of human motion monitoring.
研究领域:
材料科学
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电子工程
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生物医学工程
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DOI
高影响因子
FUEL
·
2022
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IF 8.035
You Zhao,Wenkai Zhao,Yonghou Xiao,Qidong Zhao,Chengbin Li,Xiaoying Dong,Shengnan Lu
As an efficient fuel purification technique, adsorption desulphurization has attracted wide attention. Silicon oxide has been verified as a promising candidate for adsorption desulfurization reagent due to the advantages of stable structure, inexpensiveness and accessibility. However, its adsorption desulfurization performance is always weakened by the limited pore channel size leading to pore diffusion resistance over the traditional microporous silicon oxide, and it suffers from the poor shape selectivity of mesoporous silicon oxide as well. In this work, we successfully prepared a novel super microporous silica material (SMS) with a unique bimodal micro-mesoporous pore size distribution mainly around 1.2 nm, 1.6 nm and 1.8 ∼ 3.5 nm, using a pluronic triblock copolymer with approximately an average molecular weight of 3858 as template by hydrothermal synthesis. The SMS possessed the characteristics of Ia3d cubic phase and super microporous as well as mesoporous silica structure, according to the X-ray diffraction characterization as well as nitrogen adsorption isotherms. The SMS could effectively reduce the diffusion resistance and exhibit improved shape selectivity compared to microporous or mesoporous silicon oxide, respectively, by virtue of its bimodal micro-mesoporous pore size distribution. Under an optimized crystallization temperature of 100 °C for 24 h, the as-synthesized SMS displayed a notable desulfurization performance with a breakthrough capacity of 0.122 mmol S/g benzothiophene, which was significantly superior to that of traditional mesoporous silica KIT-6 (0.04 mmol S/g). Furthermore, the desulfurization performance of SMS adsorbent was not significantly reduced after three cycles of regeneration. The SMS exhibited high desulfurization capacity, easy regeneration and satisfactory regeneration performance, and it could be applied in adsorptive desulfurization technology.
研究领域:
材料科学
·
能源化学
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DOI
高影响因子
FOOD CHEMISTRY
·
2023
·
IF 8.8
Chunmiao Bo,Yinhai Li,Bin Liu,Bolin Gong,Xiaofan Tang,Guijuan Ma,Yan Li
High-selectivity and high-exclusion restricted access materials (RAMs) benefit the analysis of biological samples. Herein, triblock copolymer–functionalized poly(4-vinylbenzyl chloride- co -divinylbenzene) (P VBC/DVB ) microspheres were prepared via the sequential surface-initiated atom radical polymerization of hydrophobic styrene (St), ionic vinylimidazole (VIm), and zwitterionic sulfobetaine methacrylate (SBMA), affording RAMs with multiple interaction–adsorption sites and zwitterionic polymer exclusion sites on the internal and external surfaces of P VBC/DVB . The preferential extraction of fluoroquinolones (FQs) is realized based on the hydrophobic/π–π/ion exchange interactions due to the grafted poly-St–VIm, and the zwitterionic poly-SBMA block in the triblock copolymers can efficiently exclude various proteins. A sensitive detection method for FQs in chicken was established by solid phase extraction with RAMs as adsorbent combined with UPLC-MS/MS, achieving wide linearity (2.0–200.0 ng mL −1 ), low limit of detection (0.5 μg kg −1 ) and limit of quantification (1.5 μg kg −1 ), and good inter- and intraday precision with satisfactory recoveries (104.1%–117.7% and 115.3%–121.2% with RSDs < 12%).
研究领域:
分析化学
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生物医学工程
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DOI
PubMed
高影响因子
ACS Sustainable Chemistry & Engineering
·
2019
·
IF 6.97
Wenmei Ao,Juan Han,Lei Wang,Chunmei Li,Yanli Mao,Yun Wang
A novel fractional purification approach of crude polysaccharides with a boronic acid-tagged thermoresponsive triblock copolymer PEG113-b-PVBA49-b-PNIPAM105 was designed in this paper. The fractional precipitation of polysaccharides was realized through simple temperature regulation based on the difference in the lower critical solution temperatures of the triblock copolymer–dextran complex. The precipitated polysaccharides from the extracting solution was in a descending order of molecular weight. Under optimal conditions, four astragalus polysaccharide fractions (APS1, APS2, APS3, and APS4) with narrow distribution of molecular weights were obtained with the temperature-controlled fractional precipitation. The structural properties, monosaccharide compositions, and molecular weights of APS1, APS2, APS3, and APS4 were characterized by the Fourier transform infrared spectrum, Congo red spectrophotometric method, gas chromatography, and gel permeation chromatography. The differences in the biological activities of various APS indicate that the molecular weights of polysaccharides have an influence on the activities of APS. This novel temperature-controlled fractional precipitation method has a favorable prospect in the fractional purification of polysaccharides.
研究领域:
生物化学
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材料科学
·
药学
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DOI
高影响因子
ACS Applied Materials & Interfaces
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2016
·
IF 7.145
Yufen Li,Yuanna Sun,Ying Xiao,Guorong Gao,Shuhui Liu,Jianfeng Zhang,Jun Fu
Multiresponsive polyelectrolyte hydrogels with extraordinary toughness have great potential in soft device applications. Previously we have demonstrated a series of tough and multiresponsive hydrogels by using multifunctional triblock copolymer (Pluronic F127 diacrylate, F127DA) micelles to cross-link cationic polyelectrolyte chains into 3D network. Herein, we further synthesize negatively charged hydrogels comprising 2-acrylamido-2-methyl propylsulfonic acid (AMPS) monomers by using F127DA micelles as cross-linkers. Similar to the positive nanomicelle (NM) hydrogels, the negative NM hydrogels exhibited a compressive strength up to 59 MPa with a fracture strain up to 98%, and tensile fracture strain higher than 2000%. These charged hydrogels were actuated by electric field when immersed in salt solutions. The effects of electrolyte concentration, electric field strength, and ionic monomer content on the electric actuation behavior of these electroactive hydrogels (EAHs) have been systematically investigated. It is concluded that the electroactive hydrogels show a fast actuation rate with a bending angle up to 87° at 120 s and the bending angle was cyclically reversed upon changing bias direction without a large decrease. This study demonstrates that such tough and multiresponsive electroactive hydrogels may have great potential in sensors, actuators, switches, and artificial muscles.
研究领域:
材料科学
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软体设备工程
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生物医学工程
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DOI
PubMed
高影响因子
AUSTRALIAN JOURNAL OF CHEMISTRY
·
2016
·Vol. 70
·期 6
·712-717
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IF 1.427
Jinjun Deng,Shiping Zhan,Jingchang Wang,Zhijun Liu,Zhiyi Li
Non-fluorous triblock copolymers of poly(l-lactide)-block-hydroxypropyl-terminated poly(dimethyl siloxanes)-block-poly(l-lactide) (PLLA-HTPDMS-PLLA) with two different molecular weights in the range of 4800 to 6500 Da, were prepared by changing the ratio of HTPDMS to l-lactide (L-LA), and were used as stabilizers for the ring-opening dispersion polymerization (RODP) of L-LA to prepare poly(l-lactide) (PLLA) in supercritical carbon dioxide (ScCO2). The experimental results showed that the prepared non-fluorous triblock copolymers were very effective as new stabilizers for the RODP and fine powders of PLLA were obtained. The structure of the stabilizers and PLLA were characterized by 1H NMR and FTIR spectroscopy. The morphology of PLLA was investigated by scanning electron microscopy (SEM). The effects of the CO2-philic/lipophilic segment lengths of the stabilizers on the RODP were explored. The effects of the stabilizer concentration on the polymerization yield, molecular weight, and morphology of PLLA were investigated.
研究领域:
材料科学
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高分子化学
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DOI
高影响因子
POLYMERS FOR ADVANCED TECHNOLOGIES
·
2016
·Vol. 28
·期 6
·658-664
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IF 1.823
Qiyang Jiang,Jinmeng Hao,Yanfeng Wei,Jianxin Mu
Block and random polyhedral oligomeric silsesquioxane (POSS)/fluorinated poly aryl ether sulfone tricopolymers were synthesized using different synthetic strategies to investigate the effect of sequence distribution on their thermal, dielectric, and surface properties. Analyses indicated that all block and random copolymers showed similar growth tendency of water contact angles and T g values, downward tendency of k values with increased content of POSS. The block copolymer displayed higher T g values up to 187°C than random copolymers (173°C) under the same POSS molar percentage, which were highly related to their different sequence distribution. The dielectric constants of the tricopolymers were drastically reduced because of the presence of POSS and fluorine, and the dielectric constant could achieve as low as 2.71 (1 MHz). Besides, sequence distribution has no obvious influence on its surface properties and properties. Meanwhile, the yields of degradation residues of the tricopolymers were significantly improved by the ceramic formation from POSS moieties during thermal decomposition. Copyright © 2016 John Wiley & Sons, Ltd.
研究领域:
材料科学
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高分子化学
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高影响因子
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