FUEL
·
2018
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IF 4.908
Haiyang Tian,Hongping Quan,Zhiyu Huang,Silong Jiang
The non-hydrophobically associating water-soluble polymer (DPAM) of acrylamide (AM) and dimethylamino propyl methacrylamide (DMAPMA) was synthesized. Then pH-switchable and CO 2 ‑switchable viscoelastic liquids based on DPAM and anionic surfactant sodium dodecyl sulfate (SDS)(referred to as DPAM-SDS) were developed. When minor HCl aqueous solution was added into the DPAM and SDS aqueous mixture or CO 2 was bubbled into it, the tertiary amine groups of DPAM were protonated to form quaternary ammonium groups, some of which in the same quaternary ammonium groups of DPAM “bridged” some SDS through noncovalent electrostatic attraction, behaving like a pseudo-hydrophobically associating water-soluble polymer and forming viscoelastic fluids as checked through environmental scanning electron microscope(ESEM) and rheology. Upon removing of CO 2 or back of pH by minor NaOH aqueous solution, the quaternary ammonium species of DPAM were deprotonated back to tertiary amine groups, separating the pseudo-hydrophobically associating water-soluble polymer back to DPAM and SDS molecules, which resulted in forming low-viscosity water solution. The switchable viscoelastic conversion can be repeated.
研究领域:
化学工程
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材料科学
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产品关联
DOI
高影响因子
RSC Advances
·
2017
·Vol. 7
·期 78
·49777-49786
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IF 3.108
Zanru Guo,Hongjian Gu,Wei Ma,Qiang Chen,Zhanfeng He,Jiali Zhang,Yongxin Liu,Longzhen Zheng,Yujun Feng
The design of controllable or “signal-triggered” metal nanoparticles is one of the emerging trends in nanotechnology and advanced materials. CO2-switchable polymer-hybrid silver nanoparticles (AgNPs) were prepared by a one-pot reaction reducing AgNO3 and trithioester terminated PDEAEMA with sodium borohydride (NaBH4). The hybrids showed a long-term stability, and their size and size distribution can be easily modulated by tuning the molar ratio of polymers to AgNO3. The hybrids not only exhibit hydrophobic–hydrophilic transitions in immiscible mixed solvents, but also undergo a switchable dispersion/aggregation states upon alternately treating with CO2 and N2. Moreover, this smart hybrid was preliminarily used as catalyst for the reduction of 4-nitrophenol. The catalytic activity of the hybrids can be switched and monotonously tuned by varying the flow rate of CO2 purged into the reaction system, which may open a new avenue for tailoring the catalytic activity of metal nanoparticles toward a given reaction.
研究领域:
纳米技术
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材料科学
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催化化学
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产品关联
DOI
高影响因子
ACS Sustainable Chemistry & Engineering
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2022
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IF 9.224
Zongze Yao,Shu Mi,Bin Chen,Fei Liu,Haining Na,Jin Zhu
The acylation modification of cellulose to make it processable is an important method to utilize this green, renewable material with broad prospects. However, it usually takes several hours or even more than 20 h to obtain products with a high degree of substitution (DS) through the methods reported in the existing literature, especially for cellulose acetate (CA). In this study, rapid homogeneous acylation of cellulose is achieved in a novel CO2 switchable solvent system by using microwave heating. CA products with DS ranging from 1.83 to 2.91 can be obtained within 3–15 min by using acetic anhydride as the acylation reagent. This strategy can also be applied for the synthesis of a series of cellulose esters with different side chain lengths, and it takes only 10 min to produce cellulose esters with a DS higher than 2.20 under microwave heating. This study suggests a facile and effective method for the synthesis of cellulose esters.
研究领域:
材料科学
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化学工程
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绿色化学
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DOI
高影响因子
ANALYTICA CHIMICA ACTA
·
2024
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IF 5.7
Lin Yang,Xiaoyue Yang,Erxu Wang,Bin Lu,Li Duan
Background Pharmacokinetic studies are pivotal in drug development , focusing on absorption, distribution, and excretion of active compounds. Effective sample preparation methods play a crucial role in these studies. Traditional techniques like protein precipitation and liquid-liquid extraction often involve toxic solvents and are time-consuming. Recently, deep eutectic solvent (DES) has emerged as an eco-friendly alternative due to its high efficiency, low cost, and low toxicity. This study introduces a novel sample pretreatment method using CO 2 -switchable DES in liquid-liquid microextraction (LLME) to enhance speed, accuracy, and sensitivity in complex biological samples analysis. Results A liquid-liquid microextraction sample pretreatment method based on switchable DES combined with high-performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS) was established for the analysis of urine and tissue samples. The method was optimized through systematic investigation of key parameters, including DES type, volume, molar ratio, pH, vortex time, gas purge time, and salt addition. The resulting procedure exhibited satisfying linearity (r 2 ≥ 0.9958), good precision (RSD ≤6.01 %), desirable recovery (52.44%–98.12 %) and matrix effect (86.22%–119.30 %), and the accuracy and precision of stability were within the ±15 % limit. The proven methods were further applied to urinary excretion study and tissue distribution study of Nelumbinis plumula (NP) extract. The results indicated that the total cumulative excretion of liensinine, isoliensinine and neferine in urine within 240 h was 4.96 %, 0.66 % and 0.44 %, respectively. The tissue distribution study showed that alkaloids mainly distribute in liver, kidney, and spleen. Significance This research introduces a groundbreaking technique distinguished by its simplicity, speed, cost-effectiveness, and environmental friendliness. This approach, utilizing CO 2 -switchable DES as an extraction solvent for LLME, integrates deproteinization and removal of interfering molecules into a single step. This integration showcases its efficiency and convenience, demonstrating significant promise for various applications in the analysis of biological samples. Additionally, this study provides the first report on urinary excretion and tissue distribution of alkaloids from NP using a DES-LLME method. These findings offer valuable insights into the in vivo behavior of herbal medicine, enhancing understanding of pharmacological actions and facilitating clinical rational administration.
研究领域:
药物分析
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中药学
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分析化学
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产品关联
DOI
PubMed
高影响因子
Polymer Chemistry
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2016
·Vol. 7
·期 30
·4881-4890
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IF 5.687
Su Yan,Qi Zhang,Wen-Jun Wang,Bo-Geng Li
Herein the preparation of CO2-switchable graphene dispersions by noncovalent exfoliation of graphite in water using a CO2-switchable star copolymer surfactant is described. The copolymer is composed of a hyperbranched polyethylene (HBPE) core and multiple poly[(2-(dimethylamino)ethyl methacrylate)-co-(2-(diethylamino)ethyl methacrylate)] (P(DMAEMA-co-DEAEMA)) arms synthesized through sequential Pd-catalyzed chain walking copolymerization of ethylene and 2-(2-bromoisobutyryloxy)ethyl acrylate followed by atom transfer radical copolymerization (ATRcoP) of DMAEMA and DEAEMA. The effects of the HBPE core and P(DMAEMA-co-DEAEMA) arms on CO2-switchable efficiency were investigated. Transmission electron microscopy (TEM), atomic force microscopy (AFM), and X-ray diffraction (XRD) measurements demonstrated the formation of graphene with 90% of them having lateral dimensions of 0.5–2 μm and a thickness of 2.2–5.2 nm (2–5 layers of graphene) using HBPE-P(DMAEMA-co-DEAEMA)s as the dispersant. The average conversion of graphite to graphene was approximately 5%. The graphene dispersions could be readily aggregated by N2 bubbling and redispersed through CO2 introduction. These CO2/N2 reversible aggregation and redispersion processes were repeatable for multiple cycles. The graphene dispersions could be directly used to produce stable styrene emulsions. CO2-switchable graphene/polystyrene nanocomposite latexes were synthesized via emulsion polymerization producing latexes that are destabilized with N2 bubbling.
研究领域:
材料科学
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聚合物化学
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纳米技术
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胶体科学
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产品关联
DOI
高影响因子
Journal of Cleaner Production
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2022
·
IF 11.072
Ma Wenjing,Dai Shanshan,Li Xiaojiang,Hongsheng Lu
Oily wastes are easily generated in many processes of exploitation, solvent extraction is the common method for treating the oily waste. However, traditional solvent extractions are difficult to recycle the solvent, and oil is difficult to separated. As a low-volatility solvent, ionic liquid is simple in synthesis, low in cost, so it has good application prospect. In this work, the sustainable separation of oil from oily waste was implemented by using CO 2 -switchable ionic liquids. On the basis of solvent extraction, ionic liquids can reduced losses and costs. The CO 2 -switchable ionic liquids were prepared by poly (propylene glycol) bis(2-aminopropyl ether) D-230 and fatty acids with low volatility at the mole ratio of 1:2. Upon the alternate bubbling CO 2 and N 2, ionic liquids could be transformed alternately from water-miscible state to water-immiscible state. The water-immiscible state was bi-phasic system containing hydrophobic fatty acids and ammonium bicarbonate solution by bubbling CO 2 . Based on the bi-phasic system, the oil (kerosene, paraffin oil and crude oil) could be mixed with fatty acids, and were separated from fatty acids in the hydrophilic state upon N 2 , where the recovery rate of oil was more than 97% and fatty acids was not residual in recovered oil. Treating oily waste, the oil could be extracted from oily waste by the bi-phasic system. The ionic liquids were reused and the oil was separated by bubbling N 2 without extra additives, where the recovery rate of oil from oily waste was more than 85.57%. Due to the simplified process and negligible solvent loss, the economic benefit of recovering per barrel crude oil reached 76.7% of the price of crude oil. Compared with the existing technology , this sustainable separation is simpler, more economical and more environmentally friendly. Hence, it is expected that this sustainable separation based on CO 2 -switchable ionic liquids will meet the development of green separation with low-energy consumption.
研究领域:
环境科学
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化学工程
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材料科学
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产品关联
DOI
高影响因子
CARBOHYDRATE POLYMERS
·
2022
·
IF 10.723
Yi Sun,Wei Zhang,Shan Lu,Wenhua Miao,Meiling Chen,Fei Liu,Haining Na,Jin Zhu
Herein, a novel cellulose-based fluorescent material with amine-responsive property was developed in a CO 2 switchable solvent for the contactless, real-time, and visual monitoring of the freshness of shrimp , crab, and fish. A nucleophilic cellulose carbonate intermediate is in-situ formed upon dissolution of cellulose in the CO 2 switchable solvent, which is adopted for the highly effective grafting of poly( l -lactic acid) and amine-responsive fluorescent reagent 7-amino-4-(trifluoromethyl) coumarin onto the cellulose backbone via ring opening polymerization and nucleophilic substitution reaction, respectively. The product has good processibility, and sensitive and reversible fluorescent responsive towards ammonia. The fluorescent intensity of the material decreased significantly and its fluorescent color changed from blue to cyan, when the aquatic products got spoiled. This study indicates that the CO 2 switchable solvent has great potential for the modification of cellulose with various functionality by taking advantage of the highly active nucleophilic cellulose carbonate intermediate.
研究领域:
材料科学
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化学工程
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食品科学
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分析化学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
SEPARATION AND PURIFICATION TECHNOLOGY
·
2024
·
IF 8.1
Xin Liang,Sheng Wang,Jing Zhou,Tengfei Lu,Kaiyu Ruan,Yuqian Xia,Tong Wang
Despite the considerable attention received by switchable solvents in natural product extraction and biorefinery. To tackle this issue, the present study has the following innovative endeavors: (1) Developing an innovative high-speed homogenization assisted extraction method using the DES/SHS/H 2 O system and applying it to the integrated extraction of phenolics, flavonoids, and essential oil from Flos Chrysanthemi Indici . The switching process was characterized using 1 H NMR, the extraction process was optimized employing response surface methodology, the components of extracted essential oils were analyzed by GC–MS, and the cytotoxicity and anti-inflammatory activity of essential oils were determined through MTT and ELISA. Our findings demonstrate that the incorporation of DES can significantly augment the CO 2 switching kinetics of SHS, resulting in a 32.7 % reduction in switching time and a remarkable decrease of 73.7 % residual content within the aqueous phase. The innovative DES/SHS/H 2 O based extraction method exhibited substantial enhancements in phenolics, flavonoids, and essential oil extraction efficiency compared to conventional approaches, yielding extracts with superior chemical profiles and enhanced anti-inflammatory activity. Therefore, the proposed strategy of enhancing the CO 2 switching kinetic properties and extraction ability of SHS by incorporating DES is feasible, providing valuable guidance for the rational design of innovative smart solvent systems. The developed DES/SHS/H 2 O system, exhibiting improved performance, holds significant application and research prospects.
研究领域:
化学工程
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药学
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分析化学
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生物技术
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天然产物研究
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产品关联
DOI
高影响因子
ACS Sustainable Chemistry & Engineering
·
2022
·
IF 9.224
Su Liu,Mingqiang Tang,Jun Pang,Jintao Hu,Weijie Chen,Jie Cheng,Zewei Liu,Haihong Zhao,Rong Tan
Water-soluble single-chain polymeric nanoparticles (SCPNs), which isolated catalytic sites within a hydrophobic interior, made water-incompatible organometallic catalysis highly efficient in water. However, it is still a great challenge to conveniently control their hydrophilicity, so as to combine reactivity and recovery of the catalytic SCPNs in aqueous systems. Herein, we have developed a series of catalytic SCPNs, which possessed CO2-switchable hydrophilic/hydrophobic behavior, to realize the gas-controlled reaction and separation for asymmetric sulfa-Michael addition (SMA) in water. A novel series of CO2-switchable random copolymers were thus synthesized by copolymerization of CO2-responsive amidine derivatives with hydrophobic chiral salen FeIII monomers via reversible addition-fragmentation chain transfer polymerization. Characterization suggested their CO2-controlled self-collapse behavior in water due to CO2-switched change in hydrophilicity/hydrophobicity of the amidine moiety. The resultant CO2-switchable SCPNs provided hydrophobic, catalytic compartments for asymmetric SMA in water upon CO2 addition, giving various chiral β-keto sulfides with almost quantitative yields (90–98%) and high enantioselectivities (93–99%). When CO2 is removed by N2 bubbling, they were collapsed and spontaneously precipitated from the aqueous system for steady reuse. The gas-controlled reaction-separation approach provides an energy-efficient way to combine reactivity and recovery of catalytic SCPNs in aqueous systems, which should be quite practical in large-scale industrial applications.
研究领域:
材料科学
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化学工程
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催化
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聚合物化学
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纳米技术
✓ 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）