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以苄基氯为引发剂,氯化亚铁为催化剂,三苯基膦为配体研究了丙烯酰胺在N,N-二甲基甲酰胺中的原子转移自由基聚合,考察了聚合时间、催化剂与配体的摩尔配比、温度等因素对单体转化率、分子量的影响。结果表明:80℃下,[AM]/[C6H5CH2Cl]/[FeCl2]/[PPh3]=100/1/0.5/1时,聚丙烯酰胺分子量随单体转化率增加线性增大,ln[[MM]]0与聚合时间呈线性关系,温度对聚合特征有较大影响。 相似文献
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原子转移自由基聚合(ATRP)的研究进展 总被引:1,自引:0,他引:1
汪永彬 《化学推进剂与高分子材料》2014,(1):32-36
介绍了可以实现活性聚合的ATRP、RATRP、AGET ATRP和ARGET ATRP 4种原子转移自由基聚合的机理,综述了原子转移自由基聚合技术在合成两亲性嵌段共聚物、接枝聚合物和星型共聚物等中的研究进展。 相似文献
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使用硅烷偶联剂3–氨基丙基三乙氧基硅烷(APTES)对纳米TiO_2进行包覆,得到TiO_2-g-APTES,再通过CuBr和N,N,N',N',N'–五甲基二乙烯基三胺(PMDETA)组成的催化体系,在纳米TiO_2表面进行原子转移自由基聚合反应(ATRP)接枝聚丙烯腈(PAN),再与聚丙烯(PP)共混制得复合材料。通过傅立叶变换红外光谱分析、热失重分析、凝胶渗透色谱和透射电镜表征,结果证明成功得到分子量可控和分子量分布较窄的TiO_2-g-PAN。添加了TiO_2-g-PAN的PP复合材料的力学性能及抗老化性都得到了提高。 相似文献
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原子转移自由基聚合(ATRP)是近十几年来发展起来的高效可控/活性聚合新技术。ATRP技术自1995年发现后,将金属催化剂与配位基结合可以控制结构,获得窄分子质量分布。通过ATRP技术在膜表面和膜材料上接枝或嵌段亲水高聚物来制备抗污染、抗菌超滤膜,包括用于生物分离色谱的高效离子交换膜。由于ATRP随反应时间、反应单体和引发剂浓度可以线性控制接枝或嵌段链密度和长度,这使亲水性材料稳定的键合在疏水膜材料上,也有效调控了基膜的孔尺寸和分布,使膜的分离性能有所提高和改善。ATRP技术已成为设计和合成优良新型材料和膜的基础手段。 相似文献
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Jian-Mei Lu Xue-Wei Xia Xiang Guo Qing-Feng Xu Feng Yan Li-Hua Wang 《应用聚合物科学杂志》2008,108(5):3430-3434
Polystyrene incorporating carboxylate group as α-end was synthesized by using initiator 4-chloromethyl benzoic acid via atom transfer radical polymerization. Its ω-chlorine end-group was transformed by cumic acid, diethyl malonate, and thiol, respectively, to form end-functionalized telechelic polystyrenes. These PSts with different functionalized ω-end group (PSt 1 , PSt 2 , and PSt 3) were obtained and characterized by H NMR and TGA. This type of end-functionalized telechelic polymers can further act as polymeric ligands to form polymeric metal complexes. In this study, PSt 1 with carboxylate group at each end was allowed to react with Eu(DBM)2Cl·2H2O to afford a new polymeric complex PSt 1 -Eu(III) showing significant red-light emission. Moreover, the film of PSt 1 -Eu shows similar emission pattern with its DMF solution. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2008 相似文献
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Controlled thermoresponsive PET track‐etched membranes were synthesized by grafting N‐isopropylacrylamide (NIPAAm) onto the membrane surface via atom transfer radical polymerization (ATRP). The initial measurements were made to determine the anchoring of ATRP initiator on PET membrane surface. Thereafter, polymerization was carried out to control the mass of polymer by controlling reaction time grafted from the membrane surface and, ATR‐FTIR, grafting degree measurements, water contact angle measurements, TGA, and SEM were used to characterize changes in the chemical functionality, surface and pore morphology of membranes as a result of modification. Water flux measurements were used to evaluate the thermoresponsive capacity of grafted membranes. The results show the grafted PET track‐etched membranes exhibit rapid and reversible response of permeability to environmental temperature, and its permeability could be controlled by controlling polymerization time using ATRP method. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011. 相似文献
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A single‐pot atom transfer radical polymerization was used for the first time to successfully synthesize polyacrylonitrile with a molecular weight higher than 80,000 and a narrow polydispersity as low as 1.18. This was achieved with CuBr/isophthalic acid as the catalyst, 2‐bromopropionitrile as the initiator, and N,N‐dimethylformamide as the solvent. The effects of the solvent on the polymerization of acrylonitrile were also investigated. The induction period was shorter in N,N‐dimethylformamide than in propylene carbonate and toluene, and the rate of the polymerization in N,N‐dimethylformamide was fastest. The molecular weight of polyacrylonitrile agreed reasonably well with the theoretical molecular weight in N,N‐dimethylformamide. When chlorine was used in either the initiator or the catalyst, the rate of polymerization showed a trend of decreasing, and the molecular weight deviated from the theoretical predication significantly. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 100: 3372–3376, 2006 相似文献
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Atom transfer radical polymerization has been a very useful method in the recent advances in controlled radical polymerization. It needs an activated alkyl halide as an initiator and a copper halide as a catalyst. This investigation reports the successful application of copper thiocyanate, a catalyst with a pseudohalide anion, in the presence of different ligands such as N,N,N=,N″,N?,N?‐hexamethyltriethylenetetramine (HMTETA), pentyl‐2‐pyridylmethaneimine, and substituted bipyridine in the atom transfer radical polymerization of styrene. Among the three ligands used, HMTETA was found to be very efficient. The polymers were characterized with 13C‐NMR, matrix‐assisted laser desorption/ionization time‐of‐flight mass spectrometry, and gel permeation chromatography analysis. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 98: 1418–1426, 2005 相似文献
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The controllability of the atom transfer radical polymerization of methyl methacrylate in the polar solvent N,N‐dimethylformamide and the nonpolar solvent xylene with 4‐(chloromethyl)phenyltrimethoxysilane as an initiator and with CuCl/2,2′‐bipyridine and CuCl/4,4′‐di(5‐nonyl)‐2,2′‐bipyridine as catalyst systems was studied. Gel permeation chromatography analysis established that in the nonpolar solvent xylene, much better control of the molecular weight and polydispersity of poly(methyl methacrylate) was achieved with the CuCl/4,4′‐di(5‐nonyl)‐2,2′‐bipyridine catalyst system than with the CuCl/2,2′‐bipyridine as catalyst system. In the polar solvent N,N‐dimethylformamide, unlike in xylene, the polymerization was more controllable with the CuCl/2,2′‐bipyridine catalyst system than with the CuCl/4,4′‐di(5‐nonyl)‐2,2′‐bipyridine catalyst system. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci 104: 2751–2754, 2007 相似文献
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Hongwen Zhang Yan Jiang Yongquan Dong Hongtu Li Kai Zhang Di Wang Jingyuan Wang 《应用聚合物科学杂志》2006,102(4):3919-3926
Novel block and graft macromolecular coupling agents with well‐defined structures have been synthesized successfully by atom transfer radical polymerization (ATRP). The molecular weights and molecular weight distributions of those functional copolymers can be controlled because of the living/controlled ATRP. The structures and composition of block and graft copolymers with the monomers of butyl acrylate (BA), styrene (St), and 3‐methacryloxyl‐propyltrimethoxyl silicon (KH‐570) have been characterized by mean of 1H NMR, IR, GPC, and UV. Because the KH‐570 of macromolecular coupling agents owns strong affinity to surface hydroxyl of fillers, inorganic fillers that were treated by the macromolecular coupling agents possess some new properties, for example increasing the effect between matrix and fillers of composites. The mechanical properties and morphology of composites with macromolecular coupling agents have been investigated by the dynamic mechanical spectra and SEM. The results showed that the damping value and compatibility of composites with macromolecular coupling agents were improved greatly when compared with that of composite with small molecular coupling agent. Furthermore with different contents of BA, St, and KH‐570 in the macromolecular coupling agents, the damping value of the composites are different. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 102: 3919–3926, 2006 相似文献
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Artun Zorvaryan 《Polymer》2011,52(3):617-621
Ethylated and butylated polyethyleneimine ligands were synthesized and employed in copper catalyzed atom transfer radical polymerization of styrene and methyl methacrylate with suitable initiators in order to obtain homogeneous polymerizations, resulting in well defined polymers with low polydispersities. Linear curves drawn from kinetics and conversion-molecular weight plots indicate that all the polymerizations were successfully controlled. In ATRP reactions of S and MMA, the apparent rate of polymerization, kpapp, exhibits a plateau at [Ligand]/[CuBr] ≥ 0.5 ratio for both ligands. The apparent rate constant also decreases by increasing the alkyl chain length of the alkylated polyethyleneimine ligand. Ethylated and butylated polyethyleneimine ligands in ATRP of S and MMA were found to be faster than the existing ATRP ligands. 相似文献
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Three novel iniferter reagents were synthesized and used as initiators for the polymerizations of methyl methacrylate (MMA) and styrene (St) in the presence of copper(I) bromide and N,N,N′,N″,N″‐pentamethyldiethylenetriamine at 90 and 115°C, respectively. All the polymerizations were well controlled, with a linear increase in the number‐average molecular weights during increased monomer conversions and relatively narrow molecular weight distributions (weight‐average molecular weight/number‐average molecular weight ≤ 1.36) throughout the polymerization processes. The polymerization rate of MMA was faster in bulk than that in solution and was influenced by the different polarities of the solvents. A slight change in the chemical structures of the initiators had no obvious effect on the polymerization rates of MMA and St. The initiator efficiency toward MMA was lower than that toward St. The results of 1H‐NMR, matrix‐assisted laser desorption/ionization time‐of‐flight mass spectrum analysis, and chain‐extension experiments demonstrated that well‐defined poly(methyl methacrylate) and polystyrene bearing photolabile groups could be obtained via atom transfer radical polymerization (ATRP) with three iniferter reagents as initiators. The polymerization mechanism for this novel initiation system was a common ATRP process. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci 2007 相似文献