RSC Advances
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2022
·Vol. 12
·期 46
·29777-29784
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IF 4.036
Zhengyue Wang,Yue Zhao,Yuhan Wei
Biomaterials have drawn considerable attention in recent years because of environmental concerns. In this paper, several different poly(lactide)-b-poly(butadiene)-b-poly(lactide) (PLA-b-PB-b-PLA) triblock copolymers were synthesized by the bulk ring-opening polymerization of lactide initiated by flexible macro-initiator hydroxyl-terminated polybutadiene (HTPB) by adjusting the ratio of HTPB to lactide and the optical isomer of lactide. Afterwards, a chain-extension reaction with hexamethylene diisocyanate (HDI) was carried out to prepare (PLA-b-PB-b-PLA)n multi-block copolymers with enhanced molecular weight. The structures and properties of these block copolymers were then characterized by gel permeation chromatography (GPC), nuclear magnetic resonance (NMR), differential scanning calorimetry (DSC), atomic force microscope (AFM) and Fourier-transform infrared (FTIR). Toughening effect of the (PLA-b-PB-b-PLA)n multiblock copolymers on biodegradable poly(L-lactide) (PLLA) film was investigated and the blended film with higher (poly(D-lactide)-b-poly(butadiene)-b-poly(D-lactide))n (PDLA-b-PB-b-PDLA)n loading (15 wt%) exhibited better toughness nearly without loss of the tensile strength. The mechanical properties of the (PLA-b-PB-b-PLA)n/PLLA blended film were proved to be influenced by the different isomers of PLA and rubbery PB chains.
研究领域:
材料科学
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高分子化学
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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
Polymers
·
2022
·Vol. 14
·期 14
·2894
·
IF 4.967
Jia Qu,Qiang Yang,Wei Gong,Meilan Li,Baoyue Cao
Heavy metal ions and organic pollutants often coexist in industrial effluents. In this work, silica-di-block polymer hybrids (SiO2-g-PBA-b-PDMAEMA) with two ratios (SiO2/BA/DMAEMA = 1/50/250 and 1/60/240) were designed and prepared for the simultaneous removal of Cr(VI) and phenol via a surface-initiated atom-transfer radical polymerization process using butyl methacrylate (BA) as a hydrophobic monomer and 2-(Dimethylamino)ethylmethacrylate (DMAEMA) as a hydrophilic monomer. The removal efficiency of Cr(VI) and phenol by the hybrids reached 88.25% and 88.17%, respectively. The sample with a larger proportion of hydrophilic PDMAEMA showed better adsorption of Cr(VI), and the sample with a larger proportion of hydrophobic PBA showed better adsorption of phenol. In binary systems, the presence of Cr(VI) inhibited the adsorption of phenol, yet the presence of phenol had a negligible effect on the adsorption of Cr(VI). Kinetics studies showed that the adsorption of Cr(VI) and phenol fitted the pseudo-second-order model well. Thermodynamic studies showed that the adsorption behavior of Cr(VI) and phenol were better described by the Langmuir adsorption isotherm equation, and the adsorption of Cr(VI) and phenol were all spontaneous adsorptions driven by enthalpy. The adsorbent still possessed good adsorption capacity for Cr(VI) and phenol after six adsorption–desorption cycles. These findings show that SiO2-g-PBA-b-PDMAEMA hybrids represent a satisfying adsorption material for the simultaneous removal of heavy metal ions and organic pollutants.Keywords:silica;amphipathic;block copolymer;adsorption;Cr(VI);phenol
研究领域:
环境科学
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材料科学
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DOI
PubMed
高影响因子
Nanomaterials
·
2019
·Vol. 9
·期 3
·363
·
IF 4.034
Xinzhi Wang,Jianguo Tang,Guanghui Wang,Wei Wang,Junjie Ren,Wei Ding,Xinbo Zhang,Yao Wang,Wenfei Shen,Linjun Huang,Laurence A. Belfiore
In this research contribution, nano-aggregates have been fabricated by introducing lanthanide (Ln3+) ions into solutions of amphiphilic diblock copolymers of polystyrene-b-poly (acrylic acid) (PS-b-PAA). The coordination of acrylic acid segments to lanthanide cations induces diblock copolymer (BCPs) self-assembly in order to design stable white luminescent hybrid nanoparticles with fine uniform particle size. The introduction of Ln3+ions (Eu3+and Tb3+) bestows the micelles, precisely white light, upon excitation of 342 nm. Lanthanide coordination cross-linking of poly (acrylic acid) segments, or blocks, endows the micelles higher thermal stability than that of BCPs micelles without cross-linking. As the most important key point of this work, the regular and stable nano-particles with high emission quality can make fully flexible electroluminescent devices with self-formation or uncoordinated into polymer hosts. Instead of inorganic luminescent nanoparticles with hard cores, this method can potentially apply for fully flexible white-light emitting diodes (FFWLEDs).Keywords:nano-aggregates;diblock copolymer;fully flexible;white-light
研究领域:
材料科学
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光学
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产品关联
DOI
PubMed
高影响因子
JOURNAL OF FLUORINE CHEMISTRY
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2013
·
IF 1.939
Bingyan Jiang,Lei Zhang,Jingzhi Shi,Shoufa Zhou,Bing Liao,Hailu Liu,Jingxin Zhen,Hao Pang
A well-defined fluorine-containing copolymer with pendant epoxy groups , poly(2,2,3,4,4,4-hexafluorobutyl methacrylate-block-glycidyl methacrylate) (PHFBMA- b -PGMA), was prepared by sequential atom transfer radical polymerization (ATRP). The amphiphilic copolymer PHFBMA- b -PGMA(OH) with pendant hydroxyl groups was obtained after ring-opening reaction of the epoxy groups from PGMA. The macroinitiator agent PHFBMA-Br and its copolymers were proved to be successfully synthesized by characterization of FTIR, 1 H NMR and gel permeation chromatography (GPC). The chain growth experiment demonstrated that a linear first-order relationship was fitted under the conditions. In addition, the fluorinated copolymers with functional groups in the side chain could keep the contact angle and the advantages of fluoropolymers while improving the hydrophilic property. Meanwhile, TGA testing showed that the copolymers had better thermal stability than its homopolymer. TEM observation indicated that microspheres were embedded in the stable micelles when the final copolymer concentration of aqueous solution was 1 wt%.
研究领域:
高分子化学
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材料科学
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纳米医学
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表面科学
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生物材料
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药物递送系统
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DOI
高影响因子
JOURNAL OF INCLUSION PHENOMENA AND MACROCYCLIC CHEMISTRY
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2019
·Vol. 96
·期 1
·69-79
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IF 1.429
Duan Nannan,Ye Lin,Zhang Ai-ying,Feng Zeng-guo
Abstract A series of PPR-based multiblock copolymers were prepared by using a PPR self-assembled from a distal 2-bromoisobutyryl end-capped ferrocenyl containing derivative Br-TEG-Fc-TEG-Br with 4 β-CDs as initiator to initiate the in situ ATRP of NIPAAm in aqueous solution at room temperature. After the ATRP, about 2 β-CDs were resided on the polymeric backbone through a 7 day dialysing purification, but those β-CDs were all slipped off the polymeric chain through a further 7 day dialysing treatment. It suggested that the resulting multiblock copolymers are really the PPR-based instead of the PR-based ones showing an impeded dethreading behavior of β-CDs and the PNIPAAm blocks attached are not bulky enough as polymeric stoppers to end-cap the β-CD-TEG-Fc-TEG PPRs into the PR-based multiblock copolymers. Graphic abstract A series of PPR-based multiblock copolymers were prepared by using a PPR self-assembled from Br-TEG-Fc-TEG-Br with 4 β-CDs as initiator to initiate the aqueous ATRP of NIPAAm. After the polymerization there are about 2 β-CDs still entrapped on the polymeric chain through a 7 day dialyzing purification. Those threaded β-CDs are all slipped off the polymeric backbone through a further 7 day dialyzing treatment.
研究领域:
高分子化学
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材料科学
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产品关联
DOI
高影响因子
Journal of Physical Chemistry C
·
2023
·
IF 3.7
Ting Qu,Xue Hu,Ying Ou,Jie Wang,Fuqiang Hu,Jing Ni,Fan Cheng,Chunli Gong,Hai Liu
Robust metallic doped semiconducting networks of precise organization, over large scales and small dimensionality, hold great application potential in the basis of photocatalytic materials. Herein, a facile method to fabricate robust Au@TiO2 hierarchical nanoporous network films is reported, which is templated by thermally stable poly(4-vinylpyridine)-block-poly{11-[4-(4-butylphenylazo)phenoxy]undecyl methacrylate} (P4VP-b-PMA(11C)Az) liquid crystalline (LC) block copolymers (BCPs). A P4VP100-b-PMA(11C)Az15 thin film can self-assemble to form ∼50 nm orderly packed PMA(11C)Az periodic spheres in the P4VP matrix via a solvent-annealing process. When these spherical P4VP100-b-PMA(11C)Az15 films with different thicknesses were exposed to the sol–gel titania precursors alcohol solutions with titanium(IV) isopropoxide (TIPT) and titanium tetrachloride (TiCl4; mass ratio, 3:1), titania was well-formed in the P4VP phase during the calcination process. After a further deposition–precipitation (DP) process, ∼10 nm Au nanoparticles were homogeneously doped in robust TiO2 nanoporous network films. The photocatalytic performance of the obtained robust Au@TiO2 films was studied in detail. It displays significantly enhanced visible light photocatalytic activity. The enhancement mechanism was ascribed to the injection of hot electrons of photoexcited Au nanoparticles to robust porous TiO2 films, which was confirmed by 420 nm Xe laser-induced fast photodegradation of rhodamine B.
研究领域:
材料科学
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化学工程
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纳米技术
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产品关联
DOI
高影响因子
INDUSTRIAL & ENGINEERING CHEMISTRY RESEARCH
·
2017
·
IF 2.843
Ruoyun Li,Linbo Wu,Bo-Geng Li
In this work, PEG-mb-PPA (abbr.: PEGPA) copolymers were synthesized via chain extension/coupling of poly(ethylene glycol) (PEG) and poly(1,2-propylene adipate) (PPA) diols, and blends of commercial poly(l-lactide) (PLLA) and PEGPA were prepared via melt blending. The multiblock copolymers were characterized by 1H NMR and DSC, and the PLLA/PEGPA blends were characterized by DSC, SEM, tensile, and impact testing. Plasticization-dominant (elongation ∼250%), toughening-dominant (impact strength 33 kJ/m2), and plasticized-toughened (250%, 14 kJ/m2) blends were obtained by varying the composition and loading of PEGPA. The PLLA/PEGPA blends exhibited much more balanced mechanical properties in comparison with PEG-plasticized and PPA-toughened PLLAs, and the plasticization-dominant blends had superior performance stability in comparison with the PEG-plasticized PLLA. The SEM micrographs indicate that the immiscible PPA segment formed elongated microphases and acted as a toughener, whereas the miscible PEG segment acted as a plasticizer of PLLA and a compatibilizer of PPA. Such a synergistic effect of both segments was responsible for the balanced mechanical properties. The improved performance stability was attributed to the high molecular weight of the multiblock copolymers and the depressed crystallization of the PEG segment.
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
POLYMER DEGRADATION AND STABILITY
·
2019
·
IF 3.78
Piotr Rychter,Kamila Lewicka,Małgorzata Pastusiak,Marian Domański,Piotr Dobrzyński
Nowadays, researchers in the field of agrochemicals are trying to find effective methods to limit the excessive usage of pesticides and protect the environment. One of the most popular and promising techniques is the immobilization of pesticides using environment-friendly polymers. In the conducted research, it was demonstrated that the family of lactide/glycolide copolymers are unsuitable for this purpose due to very slow degradation in the soil. We examined influence of relatively small content of PEG blocks in newly synthesized poly( l -lactide-co-glycolide)-poly(ethylene glycol)–poly( l -lactide-co-glycolide) (PLGA–PEG–PLGA) on the degradation in soil, in activated sludge and usefulness of this terpolymers as a biodegraded carrier for the controlled release of two commonly used herbicides (Metazachlor and Pendimethalin). Presence of even small amount of PEG block in the terpolymer chain increases slightly the hydrophilicity of the polymeric chain, thereby increasing its susceptibility to hydrolytic and unexpectedly strongly to enzymatic degradation in soil environment. The amorphism of used as a carriers PLGA-PEG-PLGA terpolymers and the lack of the phenomenon of increasing the degree of crystallinity during degradation allow to achieve uniform progress of degradation, and thus is obtained a relatively constantly release of tested herbicides. In this way, it is possible to determine the optimal profile of degradation of polymer in soil and proper rate of diffusion and leaching of active agents which allows the release of herbicides in optimal and effective doses within 3–4 months of its application.
研究领域:
农业科学
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高分子化学
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环境科学
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DOI
高影响因子
JOURNAL OF MEMBRANE SCIENCE
·
2013
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IF 4.093
Zhiming Yang,Zhaogen Wang,Xueping Yao,Xiaoqiang Chen,Yong Wang
Fluorescent polymeric spheres with uniform sizes are of great interests in the measurement and calibration of the pore sizes and defects of porous media, including separating membranes. We reported the preparation of such nanospheres by dissolving amphiphilic block copolymers of polystyrene- block -poly(2-vinyl pyridine) (PS- b -P2VP) together with chromophores (perylene and pyrene) in acetic acid at elevated temperatures. Micellar nanosphere with the chromophores residing in the cores were formed through the heating-enabled micellization process. Following quaternization of the P2VP coronae gave the spheres a positively charged surface and a good water dispersibility. Scanning and transmission electron microscopy and dynamic light scattering analysis confirmed that the micellar nanospheres were uniform in size both in the dry and wet state. The micelle size and the thickness of coronae can be tuned by altering the molecular weight of the constituent blocks. Encapsulation of chromophores in the micelle cores provided a strong fluorescent emission to the micellar nanospheres, while quaternization of the P2VP coronae gave the nanospheres a greatly variable size according to pHs and salt concentrations in the surroundings. Taking advantages of their uniform size, water dispersibility, and fluorescent emission for accurate detection, we demonstrated that the micellar nanospheres were capable of characterizing pore sizes of separating membranes and detecting their large-pore defects.
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
JOURNAL OF POLYMER SCIENCE PART A-POLYMER CHEMISTRY
·
2016
·Vol. 54
·期 13
·2040-2049
·
IF 3.114
Tao Qian,Juanjuan Wang,Tiantian Cheng,Xiaoli Zhan,Qinghua Zhang,Fengqiu Chen
The poly(methyl methacrylate) -b- poly(2-[[[[2-(perfluorohexyl)]-sulfonyl]-amino]ehthyl] methacrylate) (PMMA -b- PC 6 SMA) copolymers were successfully synthesized for the first time using activator regenerated by electron transfer atom transfer radical polymerization (ARGET ATRP) method. Under optimized reaction conditions, the degree of polymerization (DP) of resulting copolymers increased approximately linearly with monomer conversion. Structures of a well-defined block copolymer were determined by GPC, FT–IR, and 1 H-NMR spectra. Results from AFM and contact angle measurements of polymer films revealed the presence of block segments derived from PC 6 SMA, as indicated by the obvious increase in hydrophobicity and oleophobicity. The relationship between surface composition and surface wetting ability was confirmed by XPS and AFM spectra. Compared with the random copolymer PMMA -co- PC 6 SMA, C 6 SMA dosages in the PMMA -b- PC 6 SMA copolymers were greatly decreased, which retained its hydrophobic and oleophobic properties. © 2016 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2016 , 54 , 2040–2049
研究领域:
高分子化学
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材料科学
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产品关联
DOI
高影响因子
LANGMUIR
·
2024
·
IF 3.7
Qiaoyun Wu,Zhuijun Xu,Ying Yu,Meilan Peng,Jie Gao,Lei Nie,Ya-Jun Cheng,Peter Müller-Buschbaum,Yonggao Xia
Nickel-rich layered oxide cathodes, such as LiNi0.5Co0.2Mn0.3O2 (NCM523), are prevalent in high-power batteries owing to their high energy density. However, these cathodes suffer from undesirable side reactions occurring at the cathode/liquid electrolyte interface, leading to inferior interface stability and poor cycle life. To address these issues, herein, an amphiphilic diblock copolymer poly(dimethylsiloxane)-block-poly(acrylic acid) (PDMS-b-PAA) along with lithium bis(trifluoromethanesulfonyl)imide (LiTFSI) is utilized for modifying the electrode surface. This modification causes a thin and stable cathode–electrolyte interface (CEI) on the surface of NCM523 particles, as evidenced by XPS, TEM, and EIS analysis. The introduction of this modified interface successfully suppresses the capacity fading of NCM523. After 200 cycles at a rate of 1.0 C, the capacity of the modified NCM523 cathode is 108.7 mAh g–1, with a capacity retention of 82.8%, while the control samples without the polymer modification display a capacity retention of 72.7%. These results outline the distinct advantage of electrode surface modification with diblock copolymers/LiTFSI for the stabilization of Ni-rich layered oxide cathodes.
研究领域:
材料科学
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电化学
·
能源存储
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产品关联
DOI
PubMed
高影响因子
JOURNAL OF MATERIALS SCIENCE
·
2019
·Vol. 55
·期 5
·2052-2067
·
IF 3.442
Hu Lijun,Qian Zhengxin,Gao Wei,Wang Xiufang,Tian Yong
A one-step soft templating strategy for synthesizing uniform and monodisperse mesoporous carbon nanospheres (UM-MCNs) with sub-100 nm size and large mesopores without using any co-solvent additives has not yet been reported. Herein, an extremely simple,effective and environment friendly strategy was first developed to prepare uniform, monodisperse polymer nanospheres (PNs) and UM-MCNs with small particle size (80–90 nm) and large mesopores (~ 6.8 nm), where F108 with long hydrophilic chains not only served as mesopore-forming reagent, but also as a dispersant reagent that facilitated uniform growth of the nanospheres, resulting in a narrow particle size distribution. Moreover, F108 could also act as a stability-driving agent, that is, the phloroglucinol/formaldehyde polymer was tightly “locked” by the long hydrophilic segments of F108 via strong hydrogen bonding. Consequently, intact carbon nanospheres with large mesopores were obtained after carbonization, and finally a three-dimensional periodic arrangement of the UM-MCNs was formed. In addition, ethanol could be used as a co-surfactant or co-solvent during self-assembly. The present strategy may not only supply a novel avenue to synthesize UM-MCNs, but also shed light on insights into the profound impact of F108 with long hydrophilic chains and ethanol on the morphology and pore size of carbon spheres.
研究领域:
材料科学
·
纳米工程
✓ 已验证
DOI
高影响因子
危险品化学品经营许可证（带存储）