MACROMOLECULES
·
2015
·
IF 5.8
Zefeng Song,Ke Wang,Chengqiang Gao,Shuang Wang,Wangqing Zhang
A new multi-stimuli-responsive homopolymer of poly[N-[2-(diethylamino)ethyl]acrylamide] (PDEAEAM), which combines the thermoresponsive and pH/CO2-responsive moieties of the diethylamino and acrylamide groups, was proposed and synthesized by RAFT polymerization. Well-defined PDEAEAM was synthesized by solution RAFT polymerization as indicated by the linear increase in the polymer molecular weight with the monomer conversion and the narrow molecular weight distribution. The appending diethylamino group in the polymer backbone was found to be crucial to determine the thermoresponse of PDEAEAM in water. The parameters including the polymerization degree, the polymer concentration, the deuterated solvent, the terminal attached on the polymer backbone, the additives of salt and urea, and pH and bubbling CO2 affecting the thermoresponse of PDEAEAM in aqueous solution at the lower critical solution temperature (LCST) were investigated. The temperature-variable 1H NMR analysis suggests that the dehydration of PDEAEAM at temperature above LCST is ascribed to the weakened hydrogen bonding between the CONHCH2 and/or (CH2N(CH2CH3)2) moieties with the solvent of water. The proposed multi-stimuli-responsive homopolymer of PDEAEAM has two advantages of (1) the convenient and controllable RAFT synthesis and (2) the pH/CO2 tunable LCST at ∼36 °C being very close to body temperature.
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
FOOD CHEMISTRY
·
2023
·
IF 8.8
Shanshan Wang,Tian Lei,Leilei Liu,Zhijian Tan
Hesperidin, also known as vitamin P, is widely studied for its distinctive potential in food and pharmaceutical industries. This work focuses on the research of CO 2 -responsive deep eutectic solvents (DESs) used as recyclable extractants for efficient extraction of hesperidin from Fertile orange peel. Reversible phase transformation of DES solution was achieved by bubbling CO 2 /N 2 . The maximum extraction yield of 22.39 mg/g was obtained for hesperidin under the following conditions: DES-6 (triethanolamine: 4-methoxyphenol = 1:1) used as extractant, water content of 35 wt%, solid–liquid ratio of 1:60 g/mL, extraction temperature of 25 °C, and ultrasonic time of 25 min, which was much higher than that extracted by methanol. Hesperidin of 74.38% was recovered in top phase after CO 2 triggering. Density function theory (DFT) results indicated that hydrogen and π - π bonds were the main factors affecting hesperidin extraction. This study provides a new idea for extracting natural bioactive compounds using recyclable extractants.
研究领域:
食品科学
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植物化学
·
药物化学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
LANGMUIR
·
2019
·
IF 3.683
Xiaojiang Li,Baogang Wang,Shanshan Dai,Hongsheng Lu,Zhiyu Huang
CO2-responsive microemulsions based on ionic liquid 1,1,3,3-tetramethylguanidine-oleic acid (TMG-OA) have been designed to provide an approach for reducing the volatilization of amine in amine-containing microemulsions effectively and exhibit reversible transitions of microstructures. The ionic liquid TMG-OA was prepared by the direct neutralization of oleic acid (HOA) and 1,1,3,3-tetramethylguanidine (TMG, one of volatile and toxic amines). From the investigations of nuclear magnetic resonance hydrogen spectrum, pH, thermogravimetry, and automatic interface tension meter, the excellent properties of switchability, stability, and surface activity of TMG-OA were demonstrated, and then the ionic liquid-based microemulsions with CO2 response were prepared with TMG-OA (surfactant), HOA (oil phase), isopropyl alcohol (IPA, cosurfactant), and water. Interestingly, for microemulsions with a higher IPA content (47.42, 44.48 wt %), sizes of microemulsions are increased upon introducing CO2 and decreased upon addition of N2/65 °C. In addition, for microemulsions with a lower IPA content (26.22 wt %), the new microemulsions with different sizes are regenerated after the phase separation of emulsions generated by introducing CO2, and incomplete recovery of microemulsions can be observed upon addition of N2/65 °C. The reversible microstructures are induced by the swelling behavior and the reduced single phase area, which are caused by the reversible conversion between TMG-OA and HOA components.
研究领域:
化学
·
材料科学
✓ 已验证
DOI
PubMed
高影响因子
LANGMUIR
·
2024
·
IF 3.7
Zhuoxue Li,Yunlei Shi,Yimian Ding,Dazhen Xiong,Zhiyong Li,Huiyong Wang,Jikuan Qiu,Xiaopeng Xuan,Jianji Wang
A Pickering emulsion is a natural microreactor for interfacial catalysis in which an emulsifier is critical. Recently, a metal–organic framework (MOF) has attracted attention to emulsify water–organic mixtures for constructing a Pickering emulsion. However, a few stimuli-responsive Pickering emulsions based on MOFs have been reported, and the MOF emulsifiers cannot be regenerated at room temperature. Herein, the Zr-MOF with a rodlike morphology is synthesized using ionic liquid as a modulator and then modified with n-(trimethoxysilylpropyl)imidazole (C3im) to prepare a series of functionalized Zr-MOFs (MOF-C3im). It is found that MOF-C3im is an excellent emulsifier to construct stable and CO2-responsive Pickering emulsions even at low content (>0.20 wt %). Notably, the emulsification and demulsification of the emulsions can be easily and reversibly switched by bubbling of CO2 and N2 alternatively at room temperature because CO2 and imidazole molecules anchored on the Zr-MOF underwent a reversible acid–base reaction, resulting in an obvious change in the wettability of the emulsifier. As a proof of concept, the reduction reactions of nitrobenzene have been successfully carried out in these Pickering emulsions, demonstrating the efficient integration as a microreactor for chemical reaction, product separation, and emulsifier recycling under ambient conditions. This strategy provides an innovative option to develop stimulus-responsive Pickering emulsions for sustainable chemical processes.
研究领域:
材料科学
·
化学工程
·
催化反应
✓ 已验证
产品关联
DOI
PubMed
高影响因子
ACS Applied Nano Materials
·
2024
·
IF 5.3
Hairong Wu,Kunpeng Hou,Guorui Xu,Genglin Li,Jiawei Chang,Tianfang Luan,Wenhao Shao,Jirui Hou
The CO2-responsive Pickering emulsions employed have garnered considerable attention across enhanced oil recovery agents, delivery of crude, and oilfield-produced fluid treatment. This study focuses on the design of an innovative type of Janus nanoparticle (JNP) and its application in the construction of CO2 stimuli-responsive Pickering emulsions. The emulsion stabilized by JNPs demonstrates swift phase separation subsequent to the injection of CO2. Furthermore, the mechanism of the CO2-stimulated responsiveness enabled by the JNPs was proposed. Based on the Schiff reaction, the synthesis of JNPs was achieved successfully via the Pickering emulsion template method. The properties of the JNPs were studied using various analytical techniques such as Fourier transform infrared, thermogravimetric analysis, scanning electron microscopy, transmission electron microscopy, etc. The developed responsive system, composed of JNPs and sodium oleate surfactant, showed high interfacial activity at the oil/water interface. The study revealed that the responsive system-stabilized Pickering emulsions could remain stable at 70 °C and room temperature for 24 and 120 h, respectively. Furthermore, the introduction of CO2 for 1.5 min resulted in phase separation because the nanoparticles lost the amphiphilic nature, triggering a significant decrease in interfacial activity and the protonation of sodium oleate surfactant inactivation. Then, the particles started to desorb from the interface. This study proposes a convenient, simple, and cost-effective approach for preparing fast CO2-responsive Pickering emulsions. It provides novel insights into the advancement of oilfield-produced fluid treatment, transportation of crude oil, and enhanced oil recovery.
研究领域:
化学工程
·
材料科学
·
石油工程
✓ 已验证
产品关联
DOI
高影响因子
LANGMUIR
·
2019
·
IF 3.683
Gaihuan Ren,Xiaoyang Zheng,Hui Gu,Wenwen Di,Zengzi Wang,Yanlin Guo,Zhenghe Xu,Dejun Sun
Cellulose nanocrystals (CNCs) with excellent biodegradability are promising biomaterials for use as responsive Pickering emulsifiers. However, the high hydrophilicity of CNCs limits their emulsification ability. Some existing studies have utilized complicated covalent modification procedures to increase the hydrophobicity of CNCs. To simplify the modification process, we prepared hydrophobically modified CNCs (CNCs-M2005) via simple and controllable electrostatic interactions with thermosensitive M2005. The obtained CNCs-M2005 exhibited temperature and CO2 dual-responsive properties. Subsequently, stable oil/water Pickering emulsions were prepared using the partially hydrophobic CNCs-M2005 at 20 °C. However, demulsification occurred when the temperature increased to 60 °C. This temperature-induced demulsification resulted from the dehydration of polyethylene oxide and polypropylene oxide, causing the aggregation of the CNCs-M2005, as shown by dynamic light scattering and transmission electron microscopy experiments. In addition, demulsification was also achieved after bubbling CO2, which was attributed to the dissociation of the partially hydrophobic CNCs-M2005. The temperature and CO2 dual-responsive biosafe Pickering emulsions open up opportunity for the design of intelligent food, cosmetic, and drug delivery systems.
研究领域:
材料科学
·
生物工程
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Nanoscale
·
2015
·Vol. 8
·期 2
·1140-1146
·
IF 7.394
Chunmei Gao,Shaoyu Lü,Mingzhu Liu,Can Wu,Yun Xiong
The synthesis and properties of CO2 responsive and fluorescent dendritic polymers, poly(amido amine)/Pluronic F127 (PAMAM/F127), are reported in this paper. The morphologies and sizes of PAMAM/F127 dendritic polymers were investigated by dynamic light scattering (DLS) and transmission electron microscopy (TEM). PAMAM/F127 dendritic polymers showed unimolecular micelle morphologies at low concentrations, and changed to multimolecular micelles at higher concentrations. Additionally, fluorescence spectra and confocal laser scanning microscopy images showed that PAMAM/F127 dendritic polymers exhibited a fluorescent enhancement response to the presence of CO2. Apart from that, the release behavior of PAMAM/F127 gels under simulated body fluids was investigated by choosing curcumin as the hydrophobic drug. The results indicated that PAMAM/F127 dendritic polymers can be used to improve the solubility of curcumin, and the drug released faster in the presence of CO2. Such CO2 responsive fluorescent dendritic polymers are potentially applicable in cellular imaging or drug controlled release.
研究领域:
材料科学
·
生物医学工程
·
药学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
ENERGY & FUELS
·
2024
·
IF 5.2
Qi Gao,Xingguang Xu,Shuai Liu,Athumani Omari Mmbuji,Yunkun Wu
CO2 foam has been identified as having significant applications in carbon capture utilization and storage (CCUS). This is attributed to its proven capability to mitigate channeling during CO2 injection effectively; meanwhile, the majority of injected CO2 can be safely stored in reservoirs through geo-sequestration. However, the high injection pressure and poor foam stability severely affect the wide employment of CO2 foam flooding. In this study, comprehensive investigations on a novel CO2-responsive foam (CRF) with desirable injectivity and noticeable longevity are presented. This novel foam system employs lauryl ether sulfate sodium (LES) and diethylenetriamine (DETA) as foaming agents, and it exhibits notable reversible CO2-responsive properties. This property enables the fluid to transit between low and high-viscosity states, enhancing foam injection performance and reducing the injection pressure. CRF is less detrimental to reservoirs compared to conventional polymer-enhanced foam (PEF) due to its ability to switch between gel-forming and gel-breaking phases using CO2/N2. In addition, rheological tests demonstrate that CRF exhibits superior high shear tolerance compared to PEF. Moreover, CRF shows greater stability and higher salt resistance compared to PEF. At a NaCl concentration of 5 × 104 mg/L, the half-life of CRF (152 min) was nearly 13 times longer than that of PEF (11 min). It is noted that CRF exhibits a higher resistance factor in high-permeability cores compared to low-permeability cores, indicating its outstanding capacity to block the channels and mitigate CO2 breakthrough. The results of the enhanced oil recovery (EOR) experiments indicated that CRF is capable of displacing more oil than PEF in fractured cores with identical experimental conditions. It is believed that CRF may be applied as a viable CCUS technique and may enlighten investigations on novel CCUS strategies.
研究领域:
石油工程
·
环境科学
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF APPLIED POLYMER SCIENCE
·
2019
·Vol. 136
·期 18
·47439
·
IF 2.188
Shanshan Guo,Yangbufan Lv,Yangwei Chen,Shaojun Cai
Global decrease in crude oil resources and frequent crude oil leaks cause the energy crisis and ecological pollution. The absorption and release of leaked crude oil through absorption materials are a necessary process for environmental protection and recycling. In this article, a CO 2 -responsive olefin copolymer was obtained by copolymerization of styrene and an amine-containing olefin monomer. The structure of resultant copolymer was characterized by FTIR; thermal properties and CO 2 -responsive morphology changes were determined by DSC/TGA and SEM, respectively. Copolymers had certain absorption capacity for toluene with absorption rate up to 180.0%. The absorbed toluene could be released upon CO 2 stimulation with desorption rate up to 84.6%. The CO 2 -responsive copolymer could be regenerated through a simple heating process and showed stable absorption–desorption performance even after being recycled for 4 times. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019 , 136 , 47439.
研究领域:
材料科学
·
环境科学
✓ 已验证
产品关联
DOI
高影响因子
APPLIED SURFACE SCIENCE
·
2021
·
IF 6.707
Xiaohan Yang,Hanbin Liu,Liwei Qian,Qingjun Meng,Haiwei Wu,Zhijian Li,Hongwei Zhou
The remediation of water that polluted by organic dyes and nanoparticles (NPs) remains a great challenge. However, second pollution of solid waste may produce if the adsorbents are not degradable or recyclable. The stimuli-responsive materials were regarded to be able to resolve this problem by reversible adsorption-desorption under stimuli. Here in this work, the surface of cellulose fibers was modified with CO 2 -responsive molecules through a simple esterification followed by an aza-Michael addition reaction. The chemical structure was confirmed with Fourier transform infrared spectra (FT-IR), X-ray photoelectron spectroscopy (XPS), x-ray diffractometer (XRD) and thermal analysis. The gas-responsiveness was demonstrated by monitoring of the pH, conductivity and surface zeta potential. Anionic dyes and negative charged NPs in water can be selectively and reversibly captured by the CO 2 -responsive surface on cellulose fibers, suggesting the inexpensive, readily available and smart cellulose fibers may find great potential in water remediation.
研究领域:
材料科学
·
环境科学
✓ 已验证
产品关联
DOI
高影响因子
INTERNATIONAL JOURNAL OF BIOLOGICAL MACROMOLECULES
·
2025
·
IF 8.5
Zhonghai Tang,Yunlan Chen,Changyong Cai,Shaoping Ma,Zhijian Tan
The extraction of Rosa roxburghii polysaccharides using conventional methods suffers from low extraction efficiency and poor selectivity. Recently, green and efficient methods of polysaccharide extraction have received increasing attention. In this study, a CO 2 -responsive ionic liquid (IL) was developed for the extraction of Rosa roxburghii polysaccharides. This IL can achieve efficient extraction, and can be recycled, and reused in the extraction process. The maximum polysaccharide extraction yield of the IL was 253 mg/g under optimal single-factor experiment conditions. Three fractionated polysaccharides, RTFP-1, RTFP-2, and RTFP-3, were obtained by further purification, and their preliminary structures were characterized. RTFP-2 and RTFP-3 showed higher antioxidant and hypoglycemic activities than RTFP-1. This IL maintains high extraction efficiency after 5 cycles and reuse. This extraction method based on a CO 2 -responsive IL provides an efficient and sustainable method for polysaccharide extraction.
研究领域:
植物学
·
生物化学
·
绿色化学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Gels
·
2024
·Vol. 10
·期 7
·449
·
IF 5
Huipeng Wang,Changhua Yang,Yongwei Zhang,Chen Wang
In order to solve the problem of gas channeling during CO2flooding in low-permeability reservoirs, a novel CO2responsive gel channeling system was prepared by using carrageenan, branched polyethylene imide and ethylenediamine under laboratory conditions. Based on the Box–Behnken response surface design method, the optimal synthesis concentration of the system was 0.5 wt% carrageenan, 2.5 wt% branchized polyethylenimide and 6.5 wt% ethylenediamine. The micromorphology of the system before and after response was characterized by scanning electron microscopy. The rheology and dehydration rate were tested under different conditions. The channeling performance and enhanced oil recovery effect of the gel system were simulated by a core displacement experiment. The experimental results show that the internal structure of the system changes from a disordered, smooth and loosely separated lamellae structure to a more uniform, complete and orderly three-dimensional network structure after exposure to CO2. The viscosity of the system was similar to aqueous solution before contact with CO2and showed viscoelastic solid properties after contact with CO2. The experiment employing dehydration rates at different temperatures showed that the internal structure of the gel would change at a high temperature, but the gel system had a certain self-healing ability. The results of the displacement experiment show that the plugging rate of the gel system is stable at 85.32% after CO2contact, and the recovery rate is increased by 17.06%, which provides an important guide for the development of low-permeability reservoirs.
研究领域:
石油工程
·
材料科学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
危险品化学品经营许可证（带存储）