Polymers
·
2019
·Vol. 11
·期 4
·599
·
IF 3.164
Chun-Na Yan,Qian Liu,Lin Xu,Li-Ping Bai,Li-Ping Wang,Guang Li
Well-defined amphiphilic diblock copolymer poly (methyl methacrylate)-b-poly (N-isopropylacrylamide) grafted hollow spheres (HS-g-PMMA-b-PNIPAM) hybrid materials were synthesized via metal-free surface-initiated atom transfer radical polymerization (SI-ATRP). The ATRP initiators α-Bromoisobutyryl bromide (BIBB) were attached onto hollow sphere surfaces through esterification of acyl bromide groups and hydroxyl groups. The synthetic ATRP initiators (HS-Br) were further used for the metal-free SI-ATRP of methyl methacrylate (MMA) and N-isopropyl acrylamide (NIPAM) using 10-phenylphenothiazine (PTH) as the photocatalyst. The molecular weight of the polymers, structure, morphology, and thermal stability of the hybrid materials were characterized via gel permeation chromatography (GPC), X-ray photoelectron spectroscopy (XPS),1H-nuclear magnetic resonance spectroscopy (1H NMR), transmission electron microscopy (TEM), Fourier transform infrared spectroscopy (FT-IR), and thermogravimetric analysis (TGA), respectively. The results indicated that the ATRP initiator had been immobilized onto HS surfaces successfully followed by metal-free SI-ATRP of MMA and NIPAM, the Br atom had located at the end of the main PMMA polymer chain, and the polymerization process possessed the characteristic of controlled/“living” polymerization. The thermal stability of the hybrid materials was increased significantly compared to the pure PMMA and PNIPAM.Keywords:hollow spheres;metal-free ATRP;SI-ATRP;10-phenylphenothiazine (PTH);thermal stability
研究领域:
材料科学
·
高分子化学
✓ 已验证
DOI
PubMed
高影响因子
POLYMER SCIENCE SERIES B
·
2023
·Vol. 65
·期 2
·103-110
·
IF 1.2
Tianchen Song,Xiang Yixin,Gao Jiangang,Shen Xianrong
Abstract In this paper, ethyl lactate was used as a green solvent for iron(III)-catalyzed activators generated by electron transfer atom transfer radical polymerizations of methyl methacrylate in the absence of any external ligand. The effects of amount and type of solvent were investigated. Most of the systems showed the typical features of reversible deactivation radical polymerization. The polymerization of methyl methacrylate with ethyl lactate as a solvent and a ligand proceeded in a controlled manner as demonstrated by the first-order kinetic plot, low dispersity of polymers, an increase in polymer molecular weight with rise of the monomer conversion and by chain extension experiments.
研究领域:
材料科学
·
聚合物化学
✓ 已验证
DOI
高影响因子
POLYMER
·
2015
·
IF 3.562
Huanhuan Liu,Xiao Jiang,Rongjian Bian,Min Tong,Dandan Tang,Xiangdong Zhou,Youliang Zhao
Controlled synthesis of A 2m B 2n -type (m ≈ n ≈ 8) starlike copolymers comprising an oligomeric poly(styrene- co -maleimide) core and two types of V-shaped arms individually generated by ATRP and ROP was described. Multistep syntheses involving RAFT copolymerization , end group removal, ATRP of vinyl monomers such as styrene (St), methoxyethyl methacrylate (MEMA) and tert -butyl acrylate ( t BA), and ROP of ε -caprolactone (CL) were used to construct the target miktoarm stars with controlled molecular weight and relatively low polydispersity (PDI = 1.07–1.22). The resultant star copolymers had high bromide functionality and uniform chain length of ATRP-generated arms, evident from chain extension polymerization and cleavage of arms. Meanwhile, a pH-responsive (PAA) 2m (PCL) 2n star was also obtained by selective hydrolysis. The synthetic strategy via combination of RAFT copolymerization and “core first” approach is versatile in constructing various A 2m B 2n stars, and this study further paves way for facile synthesis and properties of new types of miktoarm stars.
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
Scientific Reports
·
2019
·Vol. 9
·期 1
·1-9
·
IF 4.011
Zhou Yihang,Wang Kai,Hu Dongbo
To explore new methods to maintain the dimensional stability of waterlogged archaeological wood after drying and keep the natural cell lumens unaltered for future retreatments, activator regenerated by electron transfer (ARGET) atom transfer radical polymerization (ATRP) is employed to consolidate archaeological wood. To prepare the ATRP process, the waterlogged archaeological wood samples ( Pinus massoniana with maximum moisture content of around 529%) were first modified by 2-bromoisobutyryl bromide in CH 2 Cl 2 to acquire C-Br bonds as initiators. Then, butyl methacrylate or styrene was polymerized to the remaining cell walls with catalyst (CuBr 2 ), reductant (ascorbic acid) and ligand (PMDETA) in ethanol. After the treatment, the samples were washed and naturally dried. The results characterized by microscopy showed that the polymerization only took place within the remaining cell walls, showing no sign of collapse or distortion after air drying, and all natural cell lumens could be retained for future retreatments. Also, anti-shrinkage efficiencies as high as 87.8% for the wood sample grafted with polystyrene and 98.5% for the wood sample grafted with polybutylmethacrylate were obtained from the treatment described in this paper, indicating modification of grafting polymer through ARGET ATRP can help maintain the dimensional stability of water archaeological wood effectively.
研究领域:
考古学
·
聚合物化学
·
文物保护科学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
CELLULOSE
·
2019
·Vol. 27
·期 2
·743-753
·
IF 3.917
Chen Junyu,Mao Liucheng,Qi Hongxu,Xu Dazhuang,Huang Hongye,Liu Meiying,Wen Yuanqing,Deng Fengjie,Zhang Xiaoyong,Wei Yen
Abstract In recent years, cellulose nanocrystal (CNC) based materials have attracted great research attention for different applications owing to their unique properties and facile modification chemistry. In this work, CNC based thermo-responsive fluorescent composites were successfully prepared via the metal-free surface-initiated atom transfer radical polymerization (ATRP) of NIPAAm and a Schiff base containing dye (HDPAP). Results demonstrated CNC-poly (NIPAAm–HDPAP) composites display sensitive temperature-responsive coil-to-globule transition behavior at the temperature of lower critical solution temperature. The bright fluorescence offered by the Schiff base dye (HDPAP) was also confirmed by fluorescence spectra. Moreover, the preparation method of light meditated ATRP was proved to become the promising way in fabrication of multifunctional nanomaterials for its incomparable advantages, including low energy consumption, high efficiency, good monomer adaptation, free of transition metal ions. Graphic abstract
研究领域:
材料科学
·
高分子化学
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF POLYMER SCIENCE
·
2020
·Vol. 58
·期 4
·519-527
·
IF 0
Minglu Shao,Xiangan Yue,Tianqi Yue,Jie He
A novel activators regenerated by electron transfer (ARGET) atom transfer radical polymerization (ATRP) initiation system composing of an initiator sodium chloroacetate, a catalyst ferric chloride, and a reducing agent ascorbic acid was developed to improve the gelation time of the in situ crosslinked polymer system. The kinetics of polymerization of acrylamide showed features of a living/controlled process in which the concentrations of the growing radicals [P·] are kept constant throughout the polymerization process. Compared with conventional potassium persulfate initiators, the gelation time of the in situ crosslinked polymer system can be improved to 40 h or even longer using the ARGET ATRP initiation system at 80 °C due to the low radical concentration and slow polymerization reaction. Core flooding test showed that the ARGET ATRP initiating system developed could initiate the polymerization reaction of the in situ crosslinked polymer system in the core. However, the gelation time was extended in comparison to that of the result obtained in the bottle, resulting from the dilution and adsorption of ARGET ATRP components during the injection process. The research expands the application field of the ARGET ATRP principle and has a promising prospect on controlling the gelation time of the in situ crosslinked polymer system. © 2020 Wiley Periodicals, Inc. J. Polym. Sci. 2020 , 58 , 519–527 Graphical Environment-friendly activators regenerated by electron transfer (ARGET) atom transfer radical polymerization (ATRP) initiating system were successfully developed for the regulation of the gelation time of the in situ crosslinked polymer system for the first time. Compared to the traditional initiators, the gelation time can be significantly extended due to the slower reaction and lower radical concentration in an ARGET ATRP.
研究领域:
高分子化学
·
石油工程
·
材料科学
✓ 已验证
产品关联
DOI
POLYMER SCIENCE SERIES B
·
2019
·Vol. 61
·期 3
·240-246
·
IF 0.907
Xian Rong Shen,Xiang Yi Xin,Gao Jian Gang
Abstract Supplemental activator and reducing agent atom transfer radical polymerization (SARA ATRP) of methyl acrylate was successfully performed in inexpensive, eco-friendly polyethylene glycol solvents and catalyzed by a mixed sulfite/CuBr 2 system at room temperature. The presence of polyethylene glycol in the reaction mixtures allowed fast and controlled polymerizations throughout the whole reaction time. Remarkably, a fast polymerization can be achieved with a monomer conversion reaching 90% in only 50 min using PEG 200 as the reaction solvent. The controlled character of the ATRP of methyl acrylate was confirmed by the linear increase in molecular weight with monomer conversion, the narrow molecular weight distributions ( M w / M n = 1.15) and the results of chain extension experiments. 1 H NMR analysis also confirmed the molecular structure and chain-end functionality of the obtained polymers, and the effects of PEG molecular weight and inorganic sulfites on the polymerization behavior were investigated.
研究领域:
材料科学
·
化学工程
✓ 已验证
产品关联
DOI
高影响因子
RSC Advances
·
2019
·Vol. 9
·期 43
·24659-24669
·
IF 3.049
Zheng Li,Zijian He,Xiaodan Chen,Yi Tang,Shiwen You,Yufang Chen,Tao Jin
This paper reports on the hydrophobic modification of cotton fabric grafted with 1-octadecene via an activators regenerated by electron transfer (ARGET) atom transfer radical polymerization (ATRP) mechanism. Particularly, the activation treatment of raw cotton fabric, its influence on the graft-copolymerization by the ARGET-ATRP method, along with the super-hydrophobicity and hydrophobic stability of the modified cotton fabric are discussed. Furthermore, the microstructure and elemental variation were characterized by scanning electron microscopy (SEM), atomic force microscopy (AFM), X-ray photoelectron spectroscopy (XPS), and the energy dispersion spectrum (EDS) technique. The results show that chemical activation of the raw cotton fabric can significantly improve the follow-up hydrophobic modification process. Specifically, the contact angle of the hydrophobically modified cotton fabric increased to 145° after activation, and thus, this fabric presents more stable hydrophobicity (corresponding to a 5.5% contact angle attenuation) than a non-activated fabric. The hydrophobic modification reaction was carried out using a chemically optimum stoichiometric ratio of m(CuBr2) : m(C9H23N3) : m(C2H5OH) : m(C18H36) : m(C6H8O6) = 0.015 : 0.052 : 17.9 : 2.4 : 0.05, at a temperature of 30–55 °C over 8 h. Furthermore, the SEM and AFM images revealed that more copolymer micro/nano-level particles were present on the surface of the fibers of the hydrophobically modified cotton fabric, indicating that the hydrophobic property and stability of the cotton fabric increase with the grafting density on the cotton fabric.
研究领域:
高分子化学
·
纺织材料科学
·
表面工程
·
功能材料
·
纳米技术
✓ 已验证
DOI
高影响因子
NEW JOURNAL OF CHEMISTRY
·
2022
·Vol. 46
·期 36
·17479-17486
·
IF 3.925
Zhenzhen Cui,Liang Guo,Zhenyu Jin,Lele Ma,Huaixia Yang,Mingsan Miao
Ochratoxin A (OTA) seriously affects the quality of herbal medicines and threatens the health of patients. Therefore, accurate detection of OTA in herbs is of great significance. Here, we fabricated a signal-off fluorescent biosensor for the highly sensitive detection of OTA by the activator regenerated by electron transfer atom transfer radical polymerization (ARGET ATRP) signal amplification technique. First, the specific aptamer sequence was immobilized on carboxylic MBs by an amide reaction. At the same time, the initiator was attached to the cDNA. Then the aptamer and cDNA formed a double helix structure through complementary base pairing. Afterwards, numerous fluorescent monomers were grafted onto the cDNA by ARGET ATRP, which emitted strong fluorescence. Upon addition of OTA, it could be specifically recognized by the aptamer and displace the cDNA, generating fluorescence quenching. Under optimal conditions, the detection limit of the as-prepared sensor was 7.6 fg mL−1 with a detection range of 2 × 10−3 ng mL−1 to 2 × 103 ng mL−1. Furthermore, this sensor exhibited high selectivity and reproducibility, and was successfully applied to the detection of OTA in samples of forsythia, astragalus, licorice, xanthium and malt. The outstanding performance of this biosensor suggests its possible application in the detection of mycotoxin in herbal medicine samples.
研究领域:
分析化学
·
毒理学
·
药理学
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF BIOMEDICAL MATERIALS RESEARCH PART A
·
2014
·Vol. 103
·期 2
·683-692
·
IF 2.841
Xiang Shen,Jie Liu,Xia Feng,Yiping Zhao,Li Chen
This work provides a promising way to improve the hemocompatibility of PVDF membrane. An amphiphilic copolymer (PVDF -g- PACMO) having PVDF backbones and poly( N -acryloylmorpholine) (PACMO) side chains was synthesized via atom transfer radical polymerization (ATRP). It is found that the grafting degree of the PACMO increases linearly with the increase of ACMO concentration in the reaction solution. The PVDF -g- PACMO membrane was prepared via immersed phase inversion method. The structure and performances were evaluated by X-ray photoelectron spectroscopy, field emission scanning electron microscopy, water contact angle, and filtration experiment. The hemocompatibility of the membranes were preliminarily investigated by protein adsorption, platelet adhesion, anticoagulant evaluation and hemolysis test. The results indicate that the PVDF membrane functionalized by PACMO can suppress the protein adsorption and platelet adhesion, and shows an improved hemocompatibility. © 2014 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 103A: 683–692, 2015.
研究领域:
生物医学工程
·
材料科学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
POLYMER
·
2017
·
IF 3.684
Mingsen Chen,Hongwang Zhou,Li Zhou,Faai Zhang
Rod-like mesoporous SBA-15 silica particles were surface modified by different silane coupling agents firstly, then polymethyl methacrylate (PMMA) was prepared in the confined nanopores of the SBA-15 via activators regenerated by electron transfer for atom transfer radical polymerization (ARGET ATRP). The PMMA/SBA-15 nanocomposites and PMMAs inside the nanopores were characterized by X-ray powder diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), nitrogen adsorption measurements, gel permeation chromatography (GPC), fourier transform infrared spectroscopy (FT-IR), thermogravimetry analysis (TGA), proton magnetic resonance ( 1 H NMR), and differential scanning calorimetry (DSC), respectively. The results demonstrated that the nanopores of SBA-15 could serve as nanoreactors and had great confinement effects on the MMA polymerization. The morphology of PMMAs obtained in the channels was similar to that of intrinsic structure of SBA-15. The thermal stability, molecular weights , isotacticity of PMMAs inside the pores were all increased significantly compared to the conventional PMMA by ARGET ATRP, while broadened the polydispersity index (PDI) values and reduced the syndiotacticity.
研究领域:
材料科学
·
高分子化学
✓ 已验证
DOI
高影响因子
ACS Omega
·
2022
·
IF 4.132
Shaobo Dong,Yazhen Wang,Tianyu Lan,Jianxin Wang,Liwu Zu,Tianyuan Xiao,Yonghui Yang,Jun Wang
Polystyrene (PS) is widely used in our daily life, but it is flammable and produces a large number of toxic gases and high-temperature flue gases in the combustion process, which limit its application. Improving the flame retardancy of PS has become an urgent problem to be solved. In addition, in view of the disadvantage that small-molecule flame retardants can easily migrate from polymers during use, which leads to the gradual reduction of the flame retardant effect or even loss of flame retardant performance, and the outstanding advantages of ATRP technology in polymer structure design and function customization, we used ATRP technology to synthesize the high-molecular-weight bifunctional additive PFAA-DOPO-b-PDEAEMA, which has flame retardant properties and antistatic properties. The chemical structure and molecular weight of PFAA-DOPO-b-PDEAEMA were characterized by FTIR, 1H NMR, GPC, and XPS. When the addition of PFAA-DOPO-b-PDEAEMA was 15 wt %, the limiting oxygen index (LOI) of polystyrene composites was 28.4%, which was 53.51% higher than that of pure polystyrene, the peak of the heat release rate (pHRR) was 37.61% lower than that of pure polystyrene, UL-94 reached V-0 grade, and the flame retardant index (FRI) was 2.98. In addition, when the PFAA-DOPO-b-PDEEMA content is 15 wt %, the surface resistivity and volume resistivity of polystyrene composites are 2 orders of magnitude lower than those of polystyrene. This research work provides a reference for the design of bifunctional and even multifunctional polymers.
研究领域:
材料科学
·
高分子化学
✓ 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）