JOURNAL OF POLYMER RESEARCH
·
2015
·Vol. 22
·期 3
·1-7
·
IF 1.92
Ji Yanfeng,Kang Wanli,Liu Shuren,Yang Runmei,Fan Haiming
An amphiphilic polymer in water could form an aggregate due to its hydrophobic groups. The rheological properties of the three amphiphilic polymers’ solutions are different because of their different hydrophobic groups. By using a rheometer and a rotatory viscometer, the rheological properties and apparent viscosities of three kinds of amphiphilic polymers have been studied. The results show that all of the polymers are Newtonian fluids at a low shearing rate and pseudoplastic fluids at a high shearing rate. In addition, the amphiphilic polymer-P(AM/BHAM/NaA) has the best thickening behavior and the lowest value of critical aggregation concentration (CAC), which was also verified by fluorescence spectroscopy. By combining creep-recovery with cohesive energy calculation, the structural performance and interaction energy of the aggregate is the reason for the above mentioned phenomenon. By increasing the strength of hydrophobic groups, i.e., with an oil–water partition coefficient, then the structural viscoelasticity of the groups could be improved, and the associate is easily formed in the solution.
研究领域:
高分子化学
·
物理化学
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DOI
高影响因子
ACS Applied Polymer Materials
·
2024
·
IF 4.4
Qincheng Ma,Honglin Zhou,Xiang Shao,Junbao Chen,Yujie Cheng,Mengxin Chen,Yizhang Jiang,Xiangxiang Chen,Qingping Ke,Ying Wang,Jun Tang,Yunyuan Dong,Ping Cui
Liquid–liquid biphasic reactions are widely used in academic research and industrial production; however, they have always suffered from low reactivity. In this work, a variety of linear polymeric catalysts were prepared by reversible addition–fragmentation chain transfer polymerization and postoxidation steps. The amphiphilicity of polymeric catalysts was imparted by varying the addition ratios of hydrophilic 1,1,3,3-tetramethyl-2-(4-vinylbenzyl) guanidine, hydrophobic styrene, and catalyst precursor 2,2,6,6-tetramethyl-4-piperidyl methacrylate, thus forming stable Pickering emulsions. Such Pickering emulsion systems with an abundant interfacial area and a unique interfacial environment can promote the selective oxidation reaction. As exemplified by 2,2,6,6-tetramethylpiperidinooxy-mediated oxidation of cinnamyl alcohol, the selectivity of cinnamaldehyde in Pickering emulsions was 97.2% with a turnover frequency of 5.0 mol·mol–1·min–1, which is higher than reported results. The carbon dioxide responsiveness of the guanidine group on the polymers allowed for fast demulsification after the reaction, and the recycled polymer maintained high activity after 10 runs. This polymer-stabilized Pickering emulsion provides a valuable pathway for efficient green catalytic oxidation reactions.
研究领域:
化学工程
·
材料科学
·
催化
·
绿色化学
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产品关联
DOI
高影响因子
NEW JOURNAL OF CHEMISTRY
·
2021
·Vol. 46
·期 3
·1399-1408
·
IF 3.591
Wanbing Li,Haibo Zhang,Zhaolan Zhai,Xujuan Huang,Shibin Shang,Zhanqian Song
Novel ‘bola’ rosin-based photo-responsive amphiphilic polymers PMPn (n = 17, 34, or 69) were synthesized using poly(ethylene glycol) (PEG) as a double hydrophilic head and N-azobenzenemaleimidepimaric acid (AZOMPA) as a hydrophobic tail. The relatively fixed position of the rigid group of rosin can reduce the entanglement of PEG chains and enhance the influence of the cis-isomerization of azobenzene on the volume and polarity of the entire polymer. Consequently, all polymers with different chain lengths show an extremely high photoresponsive efficiency and various morphological changes. For the PMP17 and PMP34 assemblies, collapse of the sphere micelles takes place upon UV irradiation and this process is reversible; by contrast, the PMP69 assemblies transformed from worm micelles to large spherical micelles, cloud-like micelles, large composite micelles and irregular spherical micelles. Subsequently, encapsulation of the hydrophobic fluorescent probe Nile red and as well as its release from the loaded probes triggered by UV irradiation were evaluated. The UV irradiation experiments demonstrated the photoresponsive behavior of the “bola” amphiphilic polymers PMPn containing the rigid rosin-based azobenzene group, giving an elegant strategy for design of stimuli-responsive materials.
研究领域:
材料科学
·
高分子化学
·
光化学
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DOI
高影响因子
POLYMER
·
2026
·
IF 4.5
Xiaofang Liu,Ziyan Li,Meng Zhao,Xuan Pu,Xiaoxiao Xing,Ke Wang
Photodegradable polymers containing nitrobenzyl esters groups and their derivatives (e.g., nitrobenzyl carbonate, NBC) have attracted considerable attention due to their precise UV-triggered degradation. Herein, we designed a novel NBC-containing monomer of 7-methyl-1-(2-nitrophenyl)-3-oxo-2,4,10-trioxa-7-azadodecan-12-yl methacrylate (NBC–N-EOMA) by integrating ethoxy/amino groups with NBC via precise spatial arrangement, and synthesized its homopolymer of P(NBC-N-EOMA) through reversible addition-fragmentation chain transfer (RAFT) polymerization. P(NBC-N-EOMA) exhibited triple responsiveness to temperature, pH, and light: it has a lower critical solution temperature (LCST) in pH = 5 buffer and a critical pH in aqueous solution, both regulable by the length of ethoxy chain, polymerization degree and concentration. UV/vis spectroscopy showed that after UV irradiation, the intensity of characteristic peak (265 nm) of NBC units decreased with irradiation time. 1 H NMR further revealed the reduced peak area of the methylene group in NBC, directly confirming UV-induced photodegradation, which also altered the LCST and critical pH of P(NBC-N-EOMA). Additionally, photodegradation-induced color change enabled photolithographic patterning of P(NBC-N-EOMA) on paper. Amphiphilic P(NBC-N-EOMA) self-assembled into spherical micelles with size tunable via acid or UV, and enabled controlled release of Nile Red (NR) under multi-stimuli. It also functioned as a hydrophobic block in amphiphilic diblock copolymers, retaining validated triple responsiveness and self-assembly. This work features simplified synthesis (high conversion, controllable molecular weight), high and tunable responsiveness of the homopolymer (no inter-block interference), and expandability via diverse hydrophilic blocks. Such polymers hold promise in photodegradable materials, photolithographic patterning, and biomedicine.
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产品关联
DOI
高影响因子
CARBOHYDRATE POLYMERS
·
2018
·
IF 5.158
Xuliang Lin,Linjun Wu,Siqi Huang,Yanlin Qin,Xueqing Qiu,Hongming Lou
The origin, amount, hydrophilicity, charge, molecular weight and its distribution of lignin have significant influences on the enzymatic hydrolysis of lignocellulose. The enzymatic hydrolysis of lignocellulose was essentially enhanced by lignin-based polyoxyethylene ether (EHL-PEG), whereafter followed by PEG4600 and lignosulfonate (LS). The effect of LS, EHL-PEG and PEG4600 on the adsorption and enzymatic hydrolysis kinetics of cellulase on the gold surface and cellulose film was investigated by Quartz Crystal Microbalance with dissipation monitoring (QCM-D). Results showed that the interaction of LS or EHL-PEG with cellulase was electrostatic attractive and hydrophobic effect, respectively, and formed hydrophilic cellulase aggregates. LS-Cellulase peeled off the cellulose film layer by layer, while the hydrophobic phenylpropane structure of EHL-PEG-Cellulase acted as a cellulose binding domain to hydrolysis cellulose through “Hollow” effect and made cellulose become more loose and swollen. At last, a strategy to enhance the enzymatic hydrolysis of lignocellulose by lignin-based amphiphilic polymers was proposed as well.
研究领域:
生物化学
·
材料科学
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产品关联
DOI
PubMed
高影响因子
EUROPEAN POLYMER JOURNAL
·
2022
·
IF 5.546
Lijun Wang,Fang Wang,Qiang Zhou,Yanfei Wang,Haixiang Song,Haiyang Yang
In recent years, the use of fluorescent amphiphilic polymers as the bioimaging agents has achieved significant progress, and promoted the development of the early stage cancer diagnosis and treatment. In this study, a serials of novel nitrobenzoxadiazole (NBD) fluorophore-functionalized polyester-based amphiphilic polymers were designed and synthesized via a two-step process: a hydrophobic polyester backbone was synthesized first by ring-opening alternating copolymerization (ROAC) of phthalic anhydride (PA) and allyl glycidyl ether (AGE) monomers using NBD-OH fluorophore as the initiator and metal-free Lewis pairs as the catalyst; then hydrophilic modified by three different hydrophilic pendants, PEG-SH, mercaptoacetic acid and mono-6-thio-β-cyclodextrin, through thiol-ene click reaction. Notably, directly using fluorophore as the initiator to initiate the ROAC of cyclic anhydrides and epoxides has never been reported. The influence of the feed ratio, type of Lewis pair and reaction temperature upon the polymerization performance were presented and the quantitative introduction of NBD and three kinds of hydrophilic pendants were described in detail as well. Due to the amphiphilic properties, these polymers could facilely self-assemble into fluorescent polymeric nanoparticles, which were characterized by a series of characterization techniques including surface tensiometer, dynamic light scattering (DLS), transmission electronic microscopy (TEM), and fluorescence spectroscopy. These fluorescent polymeric nanoparticles with diameters of tens or hundreds of nanometers showed good particle stability and good fluorescence performance in aqueous solution. The biocompatibility of these fluorescent polymeric nanoparticles was also excellent. In fact, the biological imaging of A549 cells could be realized successfully in the presence of the fluorescent polymeric nanoparticles. This work provides a new strategy and may inspire new approaches to the design and preparation of the biocompatible fluorescent amphiphilic polymers which could be used as the potential biological imaging agents in basic life science research and clinical applications.
研究领域:
材料科学
·
生物医学工程
·
高分子化学
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产品关联
DOI
高影响因子
Polymer Chemistry
·
2017
·Vol. 8
·期 32
·4680-4687
·
IF 5.375
Liuyan Tang,Xiuli Chen,Lei Wang,Jinqing Qu
Metallo-supramolecular hydrogels (MSH) with hydrophobic ligands were fabricated by a simple but versatile strategy. This strategy is expected to extend the selection of ligands in hydrogel systems and enables the forming hydrogels to have more attractive properties and applications. An amphiphilic polymer with a hydrophobic Schiff base ligand, poly(N,N-dimethylacrylamide-co-2-(benzylidene-hydrazonomethyl)-phenol) (P(DMA-co-BHMP)), was synthesized and self-assembled to micelles in aqueous solution. The addition of selected divalent metal ions (Cu2+, Co2+, Ca2+, Mn2+, Pb2+ and Fe2+) connected each micelle with metal–ligand coordination and resulted in gelation. The designed ligand with a pH sensitive Schiff base structure (BHMP) contributed to the pH-responsive properties of the prepared hydrogels. Rheological studies displayed that hydrogels crosslinked by Cu2+ (Cu-gel) were injectable and rapidly self-healing. The addition of competing ligands (EDTA and EDA) caused the degradation of Cu-gel. We also illuminated the reversible redox gel–sol transition of the hydrogel crosslinked by the resulting polymer and Fe2+ (Fe-gel). These self-healable and multi-stimuli responsive hydrogels have potential for biomedical and encapsulation–controlled release applications.
研究领域:
材料科学
·
生物医学工程
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DOI
高影响因子
JOURNAL OF SEPARATION SCIENCE
·
2023
·Vol. 46
·期 14
·2300112
·
IF 3.1
Zhuqiang Wu,Xiangqiong Jiang,Yanqun Yang,Rui Shi,Guihua Ruan,Yipeng Huang
In this work, amphiphilic polymers synthesized from carboxylated carbon nanotubes stabilized high internal phase emulsions are demonstrated to be capable of direct extracting zearalenone and zearalanone in samples consisting of an oil-water emulsion system. Under optimal conditions, the maximum adsorption capacities for zearalenone and zearalanone are 17.27 and 13.26 mg/g. The adsorption is mainly attributed to π-π interaction, hydrophobic interaction, and hydrogen-bonding interaction for zearalenone and zearalanone. The adsorption isotherms reveal that the adsorption of zearalenone and zearalanone on amphiphilic polymers synthesized from carboxylated carbon nanotubes stabilized high internal phase emulsions follows Freundlich model with multilayer and heterogeneous adsorption due to the presence of multiple kinds of adsorption sites. The relative recoveries of the spiked zearalenone and zearalanone in corn juice samples range from 85% to 93% with relative standard deviations lower than 3.52%. The results manifest the high efficiency of amphiphilic polymers synthesized from carboxylated carbon nanotubes stabilized high internal phase emulsions for the adsorption and separation of analytes in the oil-water emulsion system. This study provides a new perspective on adsorbent engineering for the adsorption application in heterogeneous media.
研究领域:
分析化学
·
环境科学
·
食品科学
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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）