ACS Applied Engineering Materials
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2024
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IF 0
Yan Liao,Jian Li,Chenyi Wang,Qiang Ren
Poly(3,4-ethylenedioxythiophene):poly(sodium styrenesulfonate) (PEDOT:PSS) is widely used in many aspects due to its good electrical conductivity. However, the low solid content of the PEDOT:PSS aqueous dispersion hinders its further application. Aiming to address this problem, a kind of novel “long-armed” crosslinked microspheres (cPBA@PSS), with crosslinked poly(butyl acrylate) as the core and poly(sodium styrenesulfonate) as the “long arm”, is synthesized via reversible addition–fragmentation chain transfer (RAFT) soap-free emulsion polymerization. With the “long-armed” crosslinked microspheres as the template, poly(3,4-ethylenedioxythiophene):poly(butyl acrylate-co-sodium styrenesulfonate) (PEDOT:cPBA@PSS) with a high solid content and low viscosity is successfully fabricated. The structures of cPBA@PSS are confirmed by infrared spectroscopy and hydrogen nuclear magnetic resonance spectroscopy. A PEDOT:cPBA@PSS aqueous dispersion with a solid content as high as 25 wt % is obtained by using long-armed crosslinked microspheres as the template due to the reduction of the entanglement between macromolecules. The kinetic study shows that the solid content of the dispersion has little effect on the polymerization rate of 3,4-ethylenedioxythiophene (EDOT). However, the viscosity of PEDOT:cPBA@PSS aqueous dispersions increases with an increase in the solid content. A PEDOT:cPBA@PSS aqueous dispersion with a solid content of up to 25 wt % shows a viscosity of about 37 mPa·s. The effect of the solid content on the transparency of PEDOT:cPBA@PSS films is studied, and no significant impact on film transparency is observed. The transmittance of the films at 550 nm is over 80%. The conductivity of the PEDOT:cPBA@PSS film increases with an increase in the solid content of the dispersion. The PEDOT:cPBA@PSS aqueous dispersion with a solid content of 25 wt % shows a conductivity of 0.68 S/cm when the ratio of PEDOT to cPBA@PSS is 1:1. The conductivity of the PEDOT:cPBA@PSS film can also be enhanced by secondary doping of dimethyl sulfoxide (DMSO), and the conductivity of the PEDOT:cPBA@PSS film can be increased to about 3.82 S/cm. This study shows that the use of the long-armed crosslinked microsphere cPBA@PSS as a template is an effective method to fabricate PEDOT aqueous dispersions with a high solid content and low viscosity.
研究领域:
材料科学
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高分子化学
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电化学
✓ 已验证
DOI
JOURNAL OF COLLOID AND INTERFACE SCIENCE
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2012
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IF 3.07
Shengliu Wang,Kai Yue,Lianying Liu,Wantai Yang
When dispersion polymerization of styrene (St) had run for 3 h, after particle rapidly growing stage, 4,4′-dimethacryloyloxybenzophenone (DMABP) cross-linker was added to reaction system and photoreactive, core(PSt)–shell(Poly(St- co -DMABP)) particles with rich benzophenone (BP) groups on surface were prepared. Polymerization of DMABP could occurred mainly on the preformed core of PSt because its diffusion could be impeded by (1) compactness of particles formed at the moment of cross-linker addition (more than 80% of monomer had been consumed, particles were no longer fully swollen by monomer), (2) reduced polarity of continuous phase, and (3) immediate occurrence of cross-linking. Subsequently, photoreactive, cross-linked hollow particles were yielded by removal of uncross-linked core in THF. SEM and TEM observation demonstrated the formation of core–shell structure and improvement of shell thickness when DMABP content increased. UV–vis spectra analysis on polymer dissolved in THF indicated that there is no polymer of DMABP in core. FTIR spectra analysis and XPS measurement further revealed that BP component on particle surface was enriched when amount of DMABP increased. Finally, an anti-fouling polymer (poly (ethylene glycol), PEG) and protein of mouse IgG was immobilized on particle surface under UV irradiation, as confirmed by FTIR spectra analysis, SEM observation and TMB color reaction.
研究领域:
材料科学
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生物医学工程
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Molecular Catalysis
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2024
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IF 3.9
Ming Li,Ruixia Liu,Qi Liu,Ying Liu,Yifan Liu,Qian Su,Yunong Li,Zifeng Yang
Heterogeneous ionic liquid (IL) catalysts with multiple active sites can be considered as the highly efficient catalyst for CO 2 conversion to cyclic carbonates. It is extremely challenging to achieve the strategic design and precise control of multi-site polymeric ILs’ morphology and properties. In this work, we developed a novel and facile polymerization-ionization method employing flexible brominated monomers as raw materials ( e.g. 4‑bromo-1-butene) to successfully synthesize porous hyper-cross-linked phosphonium bromide-microspheres (PBr-microspheres), in order to break through the drawbacks of multi-step preparation and difficulty in microsphere forming. Compared with conventional bromine spheres of the same size, the specific surface area of the new synthetic bromine sphere is 16 times, and the average pore size is one-eighth, with 3-times CO 2 adsorption capacity, with rich microporous structure and exposed active sites, excellent CO 2 adsorption capacity and thermal stability. PBr-microspheres can achieve synergistic effect of physical adsorption and chemical interaction for CO 2 , thus enhancing the catalytic performance in CO 2 conversion process, affording propylene oxide conversion of 99.7 % and propylene carbonate selectivity of 99.9 %, while the catalytic activity did not decrease significantly after reusing 8 runs. This facile controllable synthesis of PBr-microspheres with excellent catalytic performance provides a new idea for heterogeneous ILs-catalyzed CO 2 utilization.
研究领域:
化学工程
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材料科学
✓ 已验证
产品关联
DOI
高影响因子
ENERGY CONVERSION AND MANAGEMENT
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2017
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IF 5.589
Yaoyao Feng,Ling Li,Xin Wang,Jinbei Yang,Ting Qiu
Usually, traditional poly (ionic liquid)s are prepared to nanoparticles with high surface areas for achieving a quasi-homogeneous reaction system. In this work, a novel poly (ionic liquid) P(VB-VS)HSO 4 , synthesized by simply using ionic liquids immobilized on the 1-vinylimidazole-based crosslinked copolymer microsphere, was used as heterogeneous catalyst for transesterification of a novel non-edible feedstock soapberry oil to biodiesel. The structure, thermal stability and wetting property characteristics of the crosslinked copolymer microsphere particles and poly (ionic liquid) microspheres were investigated. The results indicated that ionic liquids were successfully functionalized on crosslinked copolymer microsphere, and P(VB-VS)HSO 4 possessed high surface areas (100.1 m 2 /g), abundant meso -macropores (with diameter of ∼18.9 nm), good mechanical strength (81 N) and superior thermal stability. Benefiting from the unique structure features, these poly (ionic liquid) microspheres manifested excellent catalytic performance for transesterification of soapberry oil with methanol. A maximum fatty acid methyl esters (FAMEs) yield of 95.2% could be obtained under the response surface methodology (RSM) optimized conditions of 8.0 h reaction time, 29.1 methanol to oil molar ratio, and 8.7 wt% catalyst amount. Impressively, it was also efficient for the esterification of oleic acid, giving methyl oleate yield of 97.5%. Catalytic tests exhibited that P(VB-VS)HSO 4 presented high catalytic activity and good reusability in comparison with traditional acid catalysts. The main physicochemical of the obtained soapberry biodiesel met the biodiesel standard ASTM D6751 . Therefore, this work provides a cheap and facile route to the synthesis of size-controlled poly (ionic liquid) microspheres (the diameter of the catalyst was about 500 μm) for catalyzing the production of clean biofuels.
研究领域:
催化化学
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能源材料
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绿色化学
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生物燃料
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高分子化学
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表面科学
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反应工程
✓ 已验证
DOI
高影响因子
NEW JOURNAL OF CHEMISTRY
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2025
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IF 2.5
Hao Liu,Yun Bai,Yabin Zhu,Bin He
Starch based particles have been developed as hemostatic products, however, the detailed in vivo degradation and metabolization were rarely reported. This paper aims to develop an absorbable starch-based hemostatic material with optimal hemostatic efficacy, and to investigate its degradation and distribution pathways using fluorescein labeling techniques. Starch is etherified to yield carboxymethyl starch (CMS), which is subsequently cross-linked with sodium trimetaphosphate (STMP) to form cross-linked carboxymethyl starch microspheres (CCMS). The water absorption swelling ratio of the cross-linked starch powder can reach 12.44 ± 0.13. The cross-linked starch powder demonstrates superior hemostatic performance and in vitro degradability compared to the commercially available absorbable starch-based hemostatic powder Surgiclean®. Subcutaneous implantation experiments revealed that CCMS implantation induced no chronic inflammation or foreign body reactions (with absence of fibrous capsule formation), indicating excellent biocompatibility. 5-(4,6-dichlorotriazinyl) amino fluorescein(5-DTAF) was immobilized on the crosslinked starch powders. The fluorescence-labeled starch hemostatic powders were applied in the abdominal and back wounds models to study the metabolism and degradation in vivo. The results showed that the degradation was started from 3 days after implantation, the degraded products were transported via blood, metabolized via kidney and excreted from urine. After 7 days, the residual amount of the degradation and metabolization products was very low, no systemic immune response and wound infection were observed during the in vivo experiments.
研究领域:
生物材料
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生物医学工程
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药学
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高分子化学
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体内成像
✓ 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）