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原子转移自由基细乳液聚合* 总被引:2,自引:0,他引:2
本文从正向、反向、同时正向/反向、电子转移活化剂等不同原子转移自由基聚合(ATRP)细乳液引发体系的角度,综述了近年来国内外关于ATRP细乳液聚合的研究进展。在细乳液体系中进行正向ATRP,聚合可控性不理想,反向ATRP相对适合于细乳液体系,其缺点是表面活性剂用量较大。同时正向/反向引发体系的ATRP中催化剂用量大为减少,并且聚合具有良好的可控性;电子转移活化剂(AGET)ATRP是通过电子转移反应来还原过渡金属的氧化态,克服了同时正向/反向ATRP中需要引入自由基引发剂的缺点。 相似文献
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Xiaoling Fu Zhen Lu Hongjie Yang Xiangyu Yin Longqiang Xiao Linxi Hou 《Journal of polymer science. Part A, Polymer chemistry》2021,59(18):2036-2044
Photoinduced atom transfer radical polymerization (ATRP) is an economical and environment-friendly method for synthesizing polymers with pre-designable structures and precise molecular weight. Although significant progress for copper-mediated photoinduced ATRP has been achieved, several drawbacks still remain, such as poor electron transfer capability and absorption bands of photocatalysts near UV region. Herein, imine-based covalent organic framework, TAPPy-TPA-COF , has been synthesized as potential heterogeneous photocatalyst for photoinduced ATRP. The “living” feature of polymerizations of methyl methacrylate (MMA) can be well controlled by efficiency maintain the balance between activation and inactivation of CuI and CuII. The chain extension experiments have further demonstrated the chain-end fidelity of polymers. Meanwhile, the catalyst recycle experiments have revealed stability of TAPPy-TPA-COF toward ATRP processes. These results support the feasibility of using COFs as heterogeneous photocatalysts for copper-mediated ATRP under visible light irradiation. 相似文献
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Katelyn M. Domingues Eric S. Tillman 《Journal of polymer science. Part A, Polymer chemistry》2010,48(24):5737-5745
Activators generated by electron transfer (AGET) was integrated into atom transfer radical coupling (ATRC) systems to drastically reduce the amount of copper catalyst required to achieve dimerization of monohalogenated polystyrene (PStX) precursors. PStCl or PStBr, prepared by ATRP, were activated and coupled in ATRC systems with varying equivalents of the reducing agent tin(II) ethyl hexanoate (Sn(EH)2) with ligand‐bound copper(I) and/or copper(II) present. Effective coupling was only observed in PStBr systems, with total copper content in the reaction mixture able to be reduced into the range of 10–25% of what is typically reported in traditional ATRC reactions of PSt while maintaining coupling yields of >50%. Additional reducing agents, glucose and ascorbic acid, were also studied and were found to be even more effective in some AGET ATRC reactions compared with Sn(EH)2. Best results were achieved with ascorbic acid as the reducing agent (>80% coupled product) with total copper content 25% of what was used for a traditional ATRC. Using an activators regenerated by electron transfer ATRP–AGET ATRC sequence resulted in an overall reduction of total copper down to 0.1–0.25% for the overall reaction sequence (compared with a traditional ATRP–ATRC sequence). © 2010 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2010 相似文献
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设计合成了星型聚合物引发剂四(2,2-二氯乙酸)季戊四醇酯(TDCAP), 并通过原子转移自由基聚合合成了八臂星型聚苯乙烯. 用FTIR, 1H NMR和GPC等手段对引发剂和星型高分子的结构进行了表征. 相似文献
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活性自由基聚合经过十多年的发展,已成为一种有效的高分子设计手段.代表性的活性自由基聚合技术包括氮氧调控自由基聚合(NMP),原子转移自由基聚合(ATRP)和可逆加成-断裂链转移(RAFT)聚合或通过黄原酸酯交换法设计大分子(MADIX).这些技术已成功应用到多数共轭单体上,但对非共轭单体的聚合控制还不太成功.本文总结了几类适合非共轭单体的活性自由基(共)聚合方法,主要有RAFT/MADIX体系,某些ATRP体系,碘退化转移体系及近年新出现的有机碲调控自由基聚合(TERP)和有机锑调控自由基聚合(SBRP)体系,其中,TERP和SBRP的独特性值得关注. 相似文献
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原子转移自由基聚合及可控自由基聚合 总被引:11,自引:0,他引:11
以作者在原子转移自由基聚合领域的研究成果为主导,结合国内外文献,对近年来出现的颇具影响的可控自由基聚合体系与进行了评述与展望。 相似文献
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Yan Shi Zhifeng Fu Bingyi Li Wantai Yang 《Journal of polymer science. Part A, Polymer chemistry》2006,44(8):2468-2475
A stable nitroxyl radical functionalized with an initiating group for atom transfer radical polymerization (ATRP), 4‐(2‐bromo‐2‐methylpropionyloxy)‐2,2,6,6‐tetramethyl‐1‐piperidinyloxy (Br‐TEMPO), was synthesized by the reaction of 4‐hydroxyl‐2,2,6,6‐tetramethyl‐1‐piperidinyloxy with 2‐bromo‐2‐methylpropionyl bromide. Stable free radical polymerization of styrene was then carried out using a conventional thermal initiator, dibenzoyl peroxide, along with Br‐TEMPO. The obtained polystyrene had an active bromine atom for ATRP at the ω‐end of the chain and was used as the macroinitiator for ATRP of methyl acrylate and ethyl acrylate to prepare block copolymers. The molecular weights of the resulting block copolymers at different monomer conversions shifted to higher molecular weights and increased with monomer conversion. © 2006 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 44: 2468–2475, 2006 相似文献
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Antibacterial poly(ethylene terephthalate) surfaces obtained from thymyl methacrylate polymerization
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Sophie Bedel Bénédicte Lepoittevin Ludovic Costa Olivier Leroy Diana Dragoe Jérôme Bruzaud Jean‐Marie Herry Morgan Guilbaud Marie‐Noëlle Bellon‐Fontaine Philippe Roger 《Journal of polymer science. Part A, Polymer chemistry》2015,53(17):1975-1985
Thymol, an antibacterial agent was used for the preparation of a methacrylic monomer. The conventional and atom transfer radical (ATRP) polymerizations of this monomer were studied using different conditions. Then, the functionalization of poly(ethylene terephthalate) (PET) films by “grafting from” ATRP using this monomer was investigated. In this aim, a three steps procedure was developed. The surfaces were first treated by NH3 plasma treatment to incorporate primary amino functions. Then, in a second step, ATRP initiator was grafted by reaction with bromoisobutyryl bromide. Surface initiated ATRP of thymyl methacrylate was performed in solution in the presence of a sacrificial initiator. The efficiency of these reactions was confirmed by X‐ray photoelectron spectroscopy. Wetting properties and surface energy were found to vary systematically depending to the type of functionalization and grafting. The poly(thymyl methacrylate)‐grafted PET surfaces exhibit resistance to bacterial adhesion toward Pseudomonas aeruginosa, Listeria monocytogenes, and Staphylococcus aureus strains. © 2015 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2015 , 53, 1975–1985 相似文献
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利用两步原子转移自由基聚合(ATRP)方法,初步建立了新型聚合物整体柱固相萃取(SPE)材料制备的新方法。首先利用ATRP方法,以乙二醇二甲基丙烯酸酯(EDMA)为交联剂,在室温条件下,在滤头中原位快速聚合制备得到负载有聚合物整体柱的萃取装置;然后采用表面诱导的电子转移活化再生原子转移自由基聚合(ARGET ATRP)方法进行表面修饰,得到了聚(二甲基氨基乙基甲基丙烯酸酯)(PDMAEMA)修饰的柱体;进一步将此整体柱用作萃取材料,实现了对激素类药物的富集分析。本研究表明:ATRP有望作为一种简单、有效及反应条件温和的聚合方法用于整体柱的制备,且该方法有潜力实现固相萃取材料在不同装置中的制备。 相似文献
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A stable nitroxyl radical functionalized with two initiating groups for atom transfer radical polymerization (ATRP), 4-(2,2-bis-(methyl 2-bromo isobutyrate)-propionyloxy)-2,2,6,6-tetramethyl-1-piperidinyloxy (Br2-TEMPO), was synthesized by reacting 4-hydroxyl-2,2,6,6-tetramethyl-1-piperidinyloxy with 2,2-bis-(methyl 2-bromo isobutyrate) propanoic acid. Stable free radical polymerization of styrene was then carried out using a conventional thermal initiator, dibenzoyl peroxide, along with Br2-TEMPO. The obtained polystyrene had two active bromine atoms for ATRP at the ω-end of the chain and was further used as the macroinitiator for ATRP of methyl acrylate and ethyl acrylate to prepare AB2-type miktoarm star-shaped copolymers. The molecular weights of the resulting miktoarm star-shaped copolymers at different monomer conversions shifted to higher molecular weights without any trace of the macroinitiator, and increased with monomer conversion. 相似文献
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Cyclopentyl methyl ether: A new green co‐solvent for supplemental activator and reducing agent atom transfer radical polymerization
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Pedro Maximiano Joana P. Mendes Patrícia V. Mendonça Carlos M. R. Abreu Tamaz Guliashvili Arménio C. Serra Jorge F. J. Coelho 《Journal of polymer science. Part A, Polymer chemistry》2015,53(23):2722-2729
A new green solvent, cyclopentyl methyl ether (CPME), is used for the first time in solvent mixtures for the successful supplemental activator and reducing agent atom transfer radical polymerization (SARA ATRP) of both activated and non‐activated monomers. The SARA ATRP of methyl acrylate (MA), glycidyl methacrylate (GMA), styrene (Sty), and vinyl chloride (VC) in CPME‐based mixtures is studied and presents similar features to those reported in the literature using other SARA ATRP systems. Moreover, CPME‐based mixtures are suitable solvents for the controlled SARA ATRP of MA using different SARA agents, such as Fe(0), Cu(0), or Na2S2O4. The chemical structure and the retention of the chain‐end functionality of the polymers are confirmed by 1H NMR and MALDI‐TOF analyses and the preparation of a well‐defined PMA‐b‐PVC‐b‐PMA triblock copolymer. The method reported here presents an additional improvement in the search for new ecofriendly ATRP systems. © 2015 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2015 , 53, 2722–2729 相似文献
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Shu-hui Qin Dong-qi Qin Kun-yuan Qiu Department of Polymer Science Engineering College of Chemistry Molecular Engineering Peking University Beijing China 《高分子科学》2001,(5):441-445
A novel photo-induced initiating system, 2, 2 - dimethoxy-2-phenylacetophenone (DMPA)/ferric tri(N,N-diethyl-dithiocarbamate) [Fe(DC)_3], was developed and used for the atom transfer radical polymerization (ATRP) of styrene intoluene. The polymerization proceeds with DMPA as photo-initiator, Fc(DC)_3 as catalyst and DC as a reversible transfergroup, while the halogen and ligands are free. Well-defined PSt was prepared and the polymerization mechanism revealed byend group analysis belongs to a reverse ATRP. Block copolymer was prepared by using thus obtained PSt as macroinitiatorand Fe(DC)_2 as catalyst under UV light irradiation via a conventional ATRP process. 相似文献
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Zhenping Cheng Xiulin Zhu Nianchen Zhou Jian Zhu Zhengbiao Zhang 《Radiation Physics and Chemistry》2005,72(6):695-701
A homogeneous solution atom transfer radical polymerization (ATRP) and reverse atom transfer radical polymerization (RATRP) of styrene (St) in N,N-dimethylformamide (DMF) were successfully carried out under pulsed microwave irradiation (PMI), using 1-bromo-1-phenylethane (1-PEBr)/CuCl/N,N,N′,N′′,N′′-pentamethyldiethylenetriamine (PMDETA) as an initiating system at 85°C and 2,2′-azo-bis-isobutyrontrile (AIBN)/CuCl2/PMDETA as an initiating system at 95°C, respectively. The polymerization rates under PMI were greatly increased in comparison with those under identical conventional heating (CH). 相似文献
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Katherine Xia Alia J. Rubaie Brendan P. Johnson Samantha A. Parker Eric S. Tillman 《Journal of polymer science. Part A, Polymer chemistry》2019,57(20):2113-2120
Monobrominated polystyrene (PSBr) was prepared by ATRP, and the resulting chain ends were activated in the presence of radical traps to induce chain end‐coupling. In atom transfer radical coupling (ATRC) with radical trap assistance, to achieve significant coupling requires excess metal catalyst, ligand, and a reducing agent that is often additional metal. In this work, activators generated by electron transfer (AGET) and radical trap assistance are used in the ATRC sequence to successfully lead to chain‐end coupling without the need for the oxidatively unstable copper (I) and with environmentally friendlier agents in place of copper metal. High extents of coupling (Xc) were achieved using ascorbic acid (AA) as the reducing agent and copper(II) bromide as the oxidized version of the catalyst, and when combined with AGET ATRP to prepare the PSBr precursor, only a fraction of the total metal was required compared to traditional atom transfer reactions, while still retaining similar Xc values. © 2019 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2019, 57, 2113–2120 相似文献