RSC Advances
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2014
·Vol. 4
·期 54
·28807-28813
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IF 3.708
Guoqiang Xu,Pengwu Xu,Dongjian Shi,Mingqing Chen
A ternary composite based on graphene oxide (GO), Fe3O4 nanoparticles and poly[2-(dimethylamino) ethyl methacrylate] (PDMAEMA) was synthesized via anchoring Fe3O4 nanoparticles onto a GO nanosheet by a facile coprecipitation method and subsequently grafting PDMAEMA to the surface by click chemistry. It was shown that the composite had a defined structure and morphology. Thermogravimetric analysis (TGA) results showed that the weight ratio of attached Fe3O4 nanoparticles was above 10.86 wt% and the surface grafting density reached above 2 chains per 10 000 carbon atoms of GO sheet. The composite exhibited good water dispersive stability depending on surface grafting density and grafted chain length. Loading and release behaviours of levofloxacin (LOFX) demonstrated that the composites had high loading capacity and pH triggered controlled release properties.
研究领域:
材料科学
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药学
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DOI
高影响因子
JOURNAL OF MEMBRANE SCIENCE
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2018
·
IF 6.578
Jindan Wu,Wei Wei,Shihong Li,Qi Zhong,Fu Liu,Jinhuan Zheng,Jiping Wang
The effect of membrane surface charge on demulsification and fouling resistance during emulsion separation is investigated. By grafting poly(2-dimethylaminoethyl methacrylate) (pDMAEMA) and poly(oligo(ethylene glycol) methacrylate) (pOEGMA) onto polypropylene (PP) membrane via ultraviolet (UV)-initiated polymerization, the obtained membranes PP- g -pDMAEMA and PP- g -pOEGMA present positive and negative surface charges in water, respectively. During the emulsion separation, PP- g -pOEGMA and PP- g -pDMAEMA membranes exhibit different separation efficiencies and pollutant resistant behaviors to the emulsions prepared from anionic surfactant (sodium dodecyl sulfate, SDS) and cationic surfactant (cetyltrimethylammonium bromide, CTAB). Comparing to PP- g -pOEGMA, the separation efficiency of PP- g -pDMAEMA was 15% (SDS emulsion) and 300% (CTAB emulsion) higher. But the flux recovery ratio of PP- g -pOEGMA was raised 30% (SDS emulsion) and 16% (CTAB emulsion). Hence, the membrane surface positive charges assist demulsification, but aggravate the membrane fouling . The mechanism obtained is beneficial to construct membranes with high separation efficiency and long-term durability.
研究领域:
材料科学
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环境工程
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DOI
高影响因子
LANGMUIR
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2017
·
IF 3.833
Jian Zhang,Ran Kou,Guangming Liu
Strong polyelectrolyte brushes (SPB) and weak polyelectrolyte brushes (WPB) have different origins with response to pH, which makes their pH-responsive properties sensitive to salt concentration in different ways. Herein, we have employed poly[2-(methacryloyloxy)ethyl trimethylammonium chloride] (PMETAC) and poly[2-(dimethylamino)ethyl methacrylate] (PDMAEMA) brushes as model systems for SPB and WPB, respectively, to investigate the effect of salt concentration on the pH responses of SPB and WPB using several surface-sensitive techniques. The pH-responsive properties of the PMETAC brushes are governed by the reorganization of the interchain hydrogen bonds between the grafted chains, whereas the pH response of the PDMAEMA brushes is controlled by the charge of the grafted chains. The response of the properties of the PMETAC brushes including hydration, conformation, and surface wettability becomes weaker with increasing salt concentration induced by the competitive adsorption of counterions to the brushes between OH– and Cl–. The weakening of the pH response of the PMETAC brushes is more remarkable at the relatively high pH values. The pH response of the PDMAEMA brushes also exhibits a salt-concentration dependence. As the salt concentration increases, the weakening of the pH response of the PDMAEMA brushes is attributed to the decrease in osmotic pressure within the brushes at relatively low pH values.
研究领域:
材料科学
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表面化学
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DOI
PubMed
高影响因子
Polymer Chemistry
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2013
·Vol. 4
·期 15
·4092-4102
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IF 5.231
Qijing Chen,Xueteng Cao,Hao Liu,Wei Zhou,Lianjie Qin,Zesheng An
Well-defined core cross-linked star (CCS) polymers of poly(N,N-dimethylaminoethyl methacrylate) (PDMAEMA) were prepared via cross-linking copolymerization in an aqueous-based dispersion polymerization system, mediated by reversible addition–fragmentation chain transfer (RAFT) polymerization. The synthesized CCS polymers were characterized by nuclear magnetic resonance (NMR) spectroscopy, gel permeation chromatography (GPC), dynamic light scattering (DLS), and conductivity and zeta potential measurements. The use of PDMAEMA CCS polymers as effective emulsifiers for oil-in-water emulsions was investigated. Interfacial tension measurements showed that the CCS polymer reduced the interfacial tension between water and oil in a pH-dependent manner. Gelled high internal phase emulsions (HIPEs) were formed at high oil fractions (80–89 vol%) and over a wide range of pH values (2–12). The HIPEs were characterized by conductivity, confocal laser scanning microscopy (CLSM) and rheology. The emulsion properties in terms of oil droplet size, long-term stability and rheology were pH-dependent. Complete demulsification of HIPEs was easily realized 2 min after the addition of base. The CCS-stabilized HIPEs were used as templates to prepare porous hydrophilic polymers by polymerizing the monomers in the continuous aqueous phase. The study presented herein reveals that responsive CCS polymers can be used as effective stabilizers for the formation of responsive HIPEs, which have a wide range of applications.
研究领域:
材料科学
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化学工程
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界面化学
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DOI
高影响因子
Soft Matter
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2011
·Vol. 7
·期 11
·5348-5352
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IF 4.457
Yin Wang,Guohua Jiang,Ming Zhang,Lina Wang,Rijing Wang,Xinke Sun
A series of novel shell cross-linked nanocapsules were facilely fabricated in an inverse miniemulsion reversible addition–fragmentation chain transfer (RAFT) system, in which poly(2-(dimethylamino)ethyl methacrylate) (PDMAEMA) acted as a stabilizer and macroinitiator. The as-prepared nanocapsules with PDMAEMA cores and poly(methylacrylic acid) (PMAA) shells, had a size of 220 nm and can be used as a carrier for the encapsulation of hydrophilic components such as inorganic salts.
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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DOI
高影响因子
COLLOIDS AND SURFACES A-PHYSICOCHEMICAL AND ENGINEERING ASPECTS
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2026
·
IF 5.4
Jiaqi Huang,Jianyu Wang,Wei Xiang,Meiping Wu,Xiaojin Miao
A dual-responsive self-healing epoxy coating was developed by incorporating a smart microcapsule (rGO@SiO₂-95S-P). PDMAEMA acted as a responsive gatekeeper, enabling faster 95S release under acidic conditions and at temperatures below its LCST range. Meanwhile, the photothermal conversion of rGO increased the coating temperature under 808 nm NIR irradiation, enhancing epoxy-chain mobility and promoting partial scratch closure. UV-Vis spectroscopy, infrared thermography, optical microscopy, electrochemical measurements, and SEM/EDS were employed to evaluate the responsive release, scratch-recovery behavior, and corrosion protection of the coating. Under NIR irradiation for 600 s, the composite coating reached 48.6 °C and exhibited an average scratch-width reduction of 0.5321 mm. After scratching and NIR treatment, the coating maintains a relatively high |Z| f= 0.01Hz of 5.08 × 10 5 Ω·cm 2 and an R ct of 8.922 × 10 5 Ω·cm 2 . At pH= 3, the composite coating exhibited an I corr of 1.286 × 10 −8 A·cm −2 and an R ct of 2.053 × 10 7 Ω·cm². SEM/EDS observations further revealed a comparatively uniform Q235 steel surface with fewer coarse corrosion products under acidic conditions. These results demonstrate that the combination of responsive inhibitor release, NIR-induced partial scratch closure, and physical barrier protection provides the composite coating with effective corrosion protection, particularly under acidic conditions. Download: Download high-res image (140KB) Download: Download full-size image
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高影响因子
ACS Applied Polymer Materials
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2021
·
IF 4.089
Xinran Wei,Daijun Chen,Xiaoli Zhao,Jinni Luo,Huanxia Wang,Pengxiang Jia
A reusable, underwater adhesive, self-healing, and conductive hydrogel was developed by the construction of an interpenetrating network structure consisting of a tungstosilicic acid (SiW) cross-linked hydroxypropyl methylcellulose (HPMC) network and a ferric ion cross-linked poly(dimethylaminoethyl methacrylate) (PDMAEMA) network. The impacts of HPMC, SiW, DMAEMA, and ferric chloride content on adhesion properties were carefully evaluated. The results demonstrated that the 3–2–0.5–60 hydrogel showed the optimal shear adhesion strength. The obtained HPMC/SiW-PDMAEMA/Fe3+ hydrogels exhibited reusable adhesion on the surfaces of various materials such as glass, wood, metals, agate, plastics, ceramics, and rubber. It was noticed that the HPMC/SiW-PDMAEMA/Fe3+ hydrogels also displayed attractive underwater adhesion performance, and they could be adhered to various substrates underwater without any pretreatment or long curing time. In addition, the HPMC/SiW-PDMAEMA/Fe3+ hydrogel showed strain-responsive conductivity and outstanding self-healing performance. Therefore, this work developed a simple method to fabricate reusable, underwater adhesive, conductive, and self-healing hydrogels, which ensure the hydrogel’s broad applicability.
研究领域:
材料科学
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化学工程
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高分子化学
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DOI
高影响因子
REACTIVE & FUNCTIONAL POLYMERS
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2019
·
IF 3.074
Dongdong Yao,Ting Li,Yaping Zheng,Zhilin Zhang
In this study, a novel hybrid nanofluid, composed of a composite core of poly(2-dimethylamino ethyl methacrylate) microgel and silica (PDMAEMA/SiO 2 ) and a shell of polyetheramine (M2070), was fabricated via a combination of inversed emulsion polymerization , biomimetic silicification and grafting onto approach. Firstly, PDMAEMA microgel of ca. 300-nm diameter with good dispersity was prepared in water/cyclohexane system. Subsequently, walnut kernel-structured and solid spherical PDMAEMA/SiO 2 composites were fabricated using swollen and contractive PDMAEMA microgel as catalytic template, respectively. Then 3-(2, 3-epoxypropoxy) propyl trimethoxysilane (KH560) modified M2070 was grafted on PDMAEMA/SiO 2 composites to obtain two kinds of solvent-free PDMAEMA/SiO 2 @M2070 hybrid nanofluids with core@shell structure. Finally, the CO 2 gas adsorption performance of these nanofluids was investigated under different CO 2 pressure (0.5–4.5 MPa) at 25 °C. The results indicated that nanofluid with walnut kernel-structured core showed more excellent CO 2 adsorption capacity than solid spherical one. Moreover, it still displayed good stability over ten adsorption-desorption cycles.
研究领域:
材料科学
·
环境科学
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产品关联
DOI
高影响因子
LANGMUIR
·
2018
·
IF 3.789
Jian Zhang,Hongtao Cai,Ling Tang,Guangming Liu
The positively charged poly(N,N′-dimethylaminoethyl methacrylate) (PDMAEMA) brushes have been employed as model weak polyelectrolyte brushes (WPBs) to demonstrate the tuning of the pH response of WPBs with specific anion effects. The charge density of PDMAEMA brushes can be modulated by specific ion-pairing interactions between counterions and the protonated dimethylamino group; as a result, the strength of the pH response of PDMAEMA brushes can be tuned by specific anion effects. A more chaotropic counterion can more strongly interact with the protonated dimethylamino group, thereby more effectively neutralizing the positively charged group associated with the grafted weak polyelectrolyte chains and more remarkably suppressing the pH response of PDMAEMA brushes. Although the pH response of PDMAEMA brushes is insensitive to the anion identity at a low salt concentration, it can be tuned by specific anion effects at relatively high salt concentrations. Our study demonstrates that the pH-responsive properties of PDMAEMA brushes including hydration, conformation, oil wettability, and adhesion can be tuned by specific anion effects. The work presented here provides a method to tune the pH response of WPBs by the anion identity.
研究领域:
材料科学
·
表面化学
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DOI
PubMed
高影响因子
FIBERS AND POLYMERS
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2022
·Vol. 23
·期 6
·1582-1594
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IF 2.347
Xu Qingbo,Wang Xinyu,Xu Wei,Zhang YanYan,Xu Zhenzhen
Immobilizing inorganic or organic particles on cotton fabric to increase the surface roughness, followed by coating with low surface reagents to reduce the surface energy, are the dominant strategies to prepare the superhydrophobic cotton surface. However, the inorganic or organic particles can easily fall off the surface of the fabrics. Thus, the surface roughness of the fabric could be reduced during the process, resulting in the poor durability of the superhydrophobic fabric. In this work, the surface of the cotton fabric was etched by cellulase. Following this, the treated fabric was grafted using a diblock copolymer (poly[(methyl methacrylate)- b -(2-(dimethylamino)ethyl)] (PMMA- b -PDMAEMA)), which was synthesized following the reversible addition-fragmentation chain transfer (RAFT) polymerization process. The mist polymerization technology was used for the process. The coatings successfully endowed the cotton fabric with superhydrophobic properties. The maximum WCA value recorded was 159.9 °. The treated fabric exhibited excellent mechanical and chemical stability. Moreover, the modified cotton sample also exhibited good self-cleaning effects in the presence of solid dust and liquid contaminants. It also exhibited excellent oil-water separation properties. Therefore, the superhydrophobic fabric prepared using a combination of the etching method and mist polymerization technology can find its potential application in home and industrial areas.
研究领域:
材料科学
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纺织工程
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表面化学
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DOI
高影响因子
CHINESE JOURNAL OF POLYMER SCIENCE
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2014
·Vol. 32
·期 7
·880-891
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IF 1.42
Sun Tian,Zhang Yu-feng,Chen Chun-lin,Gong Xiang-zhuang,Meng Jian-qiang
Surface-initiated atom transfer radical polymerization (SI-ATRP) was used to tether poly(2-dimethylaminoethyl methacrylate) (PDMAEMA) onto microporous PVDF membranes in order to synthesize membrane adsorbers for protein adsorption. The alkaline treatment and bromine addition reaction were used to anchor ATRP initiators on membrane surface. Then PDMAEMA was grafted from the membrane surface via SI-ATRP. Fourier transform infrared spectroscopy (FTIR), X-ray photoelectron spectroscopy (XPS) and scanning electron microscopy (SEM) revealed the chemical composition and surface topography of the PVDF- g -PDMAEMA membrane surfaces. These results showed that PDMAEMA was grafted from the membrane surface successfully and a grafting yield as high as 1500 μg/cm 2 was achieved. The effects of the grafting time and the density of initiators on the static and dynamic binding capacity of bovine serum albumin (BSA) were systematically investigated. Both the static and dynamic binding capacities increase with the bromination and polymerization time. However, the benefits of the initiator density on binding capacities are limited by the graft density of PDMAEMA chains.
研究领域:
材料科学
·
生物医学工程
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DOI
高影响因子
PROGRESS IN ORGANIC COATINGS
·
2016
·
IF 2.632
Jiahui Su,Xiaoxuan Liu,Chengjing Xiong,Hong Huang,Yanyan Cui
In this study, we prepared a novel triblock copolymer, PDMS- b -(PMAEBB- co -PDMAEMA) 2 ( tri -PI) bearing side-chain benzophenone (BP) and coinitiator amine, as a macro-photoinitiator via reversible addition-fragmentation chain transfer (RAFT) copolymerization of the polymerizable photoinitiator 2-(methacryloyloxy)ethyl-2-benzoylbenzoate (MAEBB) and the unsaturated coinitiator amine 2-(dimethylamino)ethyl methacrylate (DMAEMA) with a bifunctional polydimethylsiloxane (PDMS) macro-chain transfer agent (macro-CTA). The structure of synthesized copolymer was confirmed by Fourier-transform infrared spectroscopy (FT-IR), proton nuclear magnetic resonance ( 1 H NMR), differential scanning calorimetry (DSC), and gel permeation chromatography (GPC). The effects of the photoinitiator/coinitiator ratio, concentration, and photoinitiator systems on the photopolymerization kinetics of tri(propylene glycol) diacrylate (TPGDA) were investigated by real-time FT-IR. The mobility of the tri -PI chain segments was proven by X-ray photoelectron spectroscopy (XPS), and the surface morphology of TPGDA curing coatings was studied by scanning electron microscopy (SEM). Results showed that tri-PI strongly suppressed the effect of oxygen inhibition on the photopolymerization system. Tri-PI was also used in the curing of UV-curable waterborne polyurethane acrylate (UV-WPUA) resin to determine its versatility.
研究领域:
材料科学
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高分子化学
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产品关联
DOI
高影响因子
危险品化学品经营许可证（带存储）