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遥爪低聚物合成的进展 总被引:2,自引:0,他引:2
简要叙述近年来遥爪低聚物合成的发展,包括自由基聚合,阳离子聚合,基团转移聚合,开环聚合等,利用遥爪低聚物人们可按不同用途对高分子材料提出的性能要求进行聚合物的分子设计。 相似文献
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氨基氮杂环荧光分子改性苯乙烯马来酸酐共聚物的研究 总被引:2,自引:0,他引:2
荧光高分子材料 ,由于其独特光学性质 ,成为功能高分子研究热点[1~ 3 ] .一般而言 ,荧光聚合物的合成有两种方法 ,一是首先合成荧光单体 ,然后与其他适宜单体聚合 ,得到荧光聚合物 ,然而荧光单体结构复杂 ,提纯困难 ,难以获得高分子量、成膜性能好的聚合物[4] ;另一种方法是通过官能团的反应 ,用荧光物质对聚合物进行化学改性来制备[5,6] .苯乙烯 马来酸酐共聚物 (SMA)是一类成本低廉 ,性能良好的商品化聚合物材料 ,主链中含有具有反应性能的酸酐基团 ,这就使通过化学改性制备荧光聚合物成为可能 .本文通过 2 氨基苯并咪唑 ( 1 ) ,4 … 相似文献
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随着高分子化学的进步, 特别是可控自由基聚合反应的发现, 不同拓扑结构聚合物的合成己获得了巨大的进展. 为合成这些复杂结构的聚合物, 人们成功地研究了不同的聚合方法. 其中, 不同功能团引发剂方法是较为方便和可行的方法之一, 并且已广泛用于不同结构聚合物的合成. 本文综述了用该方法合成不同拓扑结构聚合物, 包括嵌段、杂臂星形、H-形、π-形、接枝和环状聚合物所取得的进展, 特别强调的是这篇论文没有覆盖这方面的所有研究工作. 这一合成方法的思路是基于将不同聚合反应, 尤其是不同可控聚合反应相结合, 或者将可控聚合与不同的偶合反应, 例如与点击反应、Diel-Alder反应和活性酯反应等相结合. 所讨论的多功能引发剂不仅包括小分子化合物, 也包括带有两个和两个以上引发基团或链转移基团的聚合物. 后者称为大分子多功能团引发剂, 可以独立引发不同的聚合反应. 相似文献
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双亲嵌段聚合物的合成与应用 总被引:8,自引:0,他引:8
本文介绍了双亲嵌段聚合物的合成方法,包括共溶剂法、聚合后功能化法、胶束聚合法、自由基界面聚合法等,以及双亲嵌段聚合物在乳液聚合、三次采油、医用高分子材料等方面的应用。 相似文献
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Derek P. Gates Chi-Wing Tsang Vincent A. Wright Mandy Yam 《Macromolecular Symposia》2003,196(1):271-278
The C=C bond plays numerous roles in polymer science. This moiety is used as a precursor to polymers by addition polymerization and has been incorporated into π-conjugated polymers. The addition polymerization reaction has been extended to P=C bonds and the first example of a poly(methylenephosphine) has been prepared. The new macromolecule is of moderate molecular weight (ca. 104 g/mol) and the oxidized polymers are air-stable. Poly(p-phenylenephosphaalkene), the first π-conjugated polymer containing P=C bonds in the backbone, has been prepared. The UV/Vis spectrum of this polymer shows a red shift in λmax when compared with molecular model systems. 相似文献
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Tomoya Higashihara Akira Hirao 《Journal of polymer science. Part A, Polymer chemistry》2004,42(18):4535-4547
A series of four-armed A2BC, AB2C, and ABC2 asymmetric star-branched polymers with a three-component system, the A, B, and C segments of which are polystyrene, polyisoprene, and poly(4-trimethylsilylstyrene), respectively, have been successfully synthesized with a methodology based on living anionic polymerization with dual-functionalized 1,1-bis(3-chloromethylphenyl)ethylene ( 1 ). These star-branched polymers have well-defined architectures and precisely controlled chain lengths, as confirmed by size exclusion chromatography, 1H and 13C NMR, vapor pressure osmometry, and static light scattering analyses. A simple and convenient one-pot process for star-branched polymer synthesis is an additional advantage of this methodology. One problem to be solved is that the synthetic route is limited in some cases by the inherently low reactivity of polyisoprenyllithium toward the 1,1-diphenylethylene functionality of in-chain-functionalized polymers. A new four-armed ABCD star-branched polymer, the A, B, C, and D segments of which are polyisoprene, poly(4-methoxystyrene), polystyrene, and poly(4-trimethylsilylstyrene), could also be synthesized through the extension of the methodology using 1 to a four-component system. The successful results strongly demonstrate the synthetic versatility and potential of this methodology for a wide variety of well-defined asymmetric star-branched polymers. © 2004 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 42: 4535–4547, 2004 相似文献
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Sung-Ho Jin Hyun-Nam Cho Sam-Kwon Choi 《Journal of polymer science. Part A, Polymer chemistry》1993,31(1):69-74
The polymerization of dipropargyl isopropylidene malonate (DPIPM) was polymerized by WCl6 and MoCl5 associated with various organometallic cocatalysts. MoCl5 was found to be the most effective catalyst and Ph4Sn was observed to have a high cocatalyst activity. Structure and physical properties of poly(DPIPM) were investigated. The spectral data indicated that poly(DPIPM) contains alternating double and single bonds along the polymer backbone and a cyclic recurring unit. The poly(DPIPM) was partially soluble in common organic solvents. The M?n values of the polymer from soluble fraction were in the range of 5100–8000 relative to polystyrene standards by GPC. In addition, poly(DPIPM) possesses good stability to air oxidition. When poly(DPIPM) is exposed to iodine vapor, the electrical conductivity was increased from 4.5 × 10?11 to 7 × 10?2 S/cm. © 1993 John Wiley & Sons, Inc. 相似文献
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Roberta Sanna Valeria Alzari Daniele Nuvoli Sergio Scognamillo Salvatore Marceddu Alberto Mariani 《Journal of polymer science. Part A, Polymer chemistry》2012,50(8):1515-1520
In this work, we report on the synthesis and characterization of homopolymers and copolymers of acrylic acid and 2‐hydroxyethyl acrylate prepared by the use of the frontal polymerization (FP) technique. Tetraethyleneglycoldiacrylate was used as a crosslinker and benzoyl peroxide as an initiator. The maximum temperatures reached by the front were in the range between 214 °C and 296 °C. Besides, front velocities ranged between 3.9 and 10.8 cm/min, the latter being one of the highest values reported so far in the FP literature. Differential scanning calorimetry was used to estimate the conversion degree, which was always comprised between 90% and 96%, and to determine the glass transition temperatures, which were found to be dependent on the composition, with values ranging from 13 °C to 168 °C. Moreover, the obtained materials were allowed to swell in aqueous solutions at various pH. The samples exhibit a moderate increase of the swelling ratio percentage (SR%) at pH ≈ 5–6, and a sudden and larger SR% increase at pH ≈ 12–13 depending on the composition, thus indicating the obtainment of pH‐responsive polymer hydrogels. © 2012 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2012 相似文献
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Itaru Natori Shizue Natori 《Journal of polymer science. Part A, Polymer chemistry》2012,50(4):772-779
Synthesis of the polymer whose end is functionalized by fac‐Ir(ppy)3 (ppy = 2‐phenylpyridyl) was achieved by using (living) anionic polymerization of 1,3‐cyclohexadiene: the reaction of poly(1,3‐cyclohexadienyl)lithium (PCHDLi) with fac‐Ir(ppy)2(vppy) [vppy = 2‐(4‐vinylphenyl)pyridyl] resulted in nucleophilic attack of the carbanion in PCHDLi on the vinyl group of fac‐Ir(ppy)2(vppy) selectively. Complexation of the pyridyl ring protected the α‐carbons of fac‐Ir(ppy)2(vppy) from the reaction of the anionic polymer. The homopolymerization of fac‐Ir(ppy)2(vppy) did not occur, and only one molecule of fac‐Ir(ppy)2(vppy) reacted with the carbanion of PCHDLi and was selectively incorporated into an end of poly(1,3‐cyclohexadiene) (PCHD). Thus, the PCHD with fac‐Ir(ppy)3 end‐group was obtained with a well‐controlled and defined polymer structure and molecular weight. © 2011 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2012 相似文献
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Synthesis of Multivalent Organotellurium Chain‐Transfer Agents by Post‐modification and Their Applications in Living Radical Polymerization
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Weijia Fan Dr. Yasuyuki Nakamura Prof. Shigeru Yamago 《Chemistry (Weinheim an der Bergstrasse, Germany)》2016,22(47):17006-17010
Functionalized or multivalent organotellurium chain‐transfer agents (CTAs) for living radical polymerization were synthesized by post‐modification, which involved the condensation between a carboxylic‐acid‐functionalized CTA and various amines in excellent yields without affecting the reactive tellurium moiety. The CTAs exhibited high synthetic versatility for radical polymerization and gave structurally well‐controlled polymers, such as multiarmed polymers, from various monomers. Because all new CTAs are easily available on a large scale by simple purification, the current method significantly facilitates macromolecular engineering based on organotellurium‐mediated radical polymerization (TERP). 相似文献
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简要叙述我国近20年来在高分子化学研究领域中的自由基聚合、光诱导聚合、Ziegler Natta聚合和茂金属聚烯烃、环醚、枘酯等开环聚合、缩聚反应合成PEEK和耐热性杂环高分子含氟高分子、生物医学高分子、导电高分子、液晶高分子方面的进展。 相似文献
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Firmin Moingeon Yan Rong Wu Lorena Eugenia Cadena‐Sánchez Mario Gauthier 《Journal of polymer science. Part A, Polymer chemistry》2012,50(9):1819-1826
The synthesis of arborescent styrenic homopolymers and copolymers was achieved by anionic polymerization and grafting. Styrene and p‐(3‐butenyl)styrene were first copolymerized using sec‐butyllithium in toluene, to generate a linear copolymer with a weight‐average molecular weight Mw = 4000 and Mw/Mn = 1.05. The pendant double bonds of the copolymer were then epoxidized with m‐chloroperbenzoic acid. A comb‐branched (or arborescent generation G0) copolymer was obtained by coupling the epoxidized substrate with living styrene‐p‐(3‐butenyl)styrene copolymer chains with Mw ≈ 5000 in a toluene/tetrahydrofuran mixture. Further cycles of epoxidation and coupling reactions while maintaining Mw ≈ 5000 for the side chains yielded arborescent copolymers of generations G1–G3. A series of arborescent styrene homopolymers was also obtained by grafting Mw ≈ 5000 polystyrene side chains onto the linear and G0–G2 copolymer substrates. Size exclusion chromatography measurements showed that the graft polymers have low polydispersity indices (Mw/Mn = 1.02–1.15) and molecular weights increasing geometrically over successive generations. © 2012 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2012 相似文献
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David A. Rankin Steven J. P'Pool Hans-Jörg Schanz Andrew B. Lowe 《Journal of polymer science. Part A, Polymer chemistry》2007,45(11):2113-2128
The authors detail herein the synthesis and controlled polymerization of a series of new permanently cationic ammonium exo-7-oxanorbornene derivatives via ROMP, with the first generation Grubbs' catalyst RuCl2(PCy3)2CHPh, in a novel solvent mixture composed of 1:1 vol/vol 2,2,2-trifluoroethanol (TFE)/methylene chloride. It is demonstrated that this cosolvent mixture is a convenient reaction medium facilitating the polymerization of hydrophilic substrates by hydrophobic initiators under homogeneous conditions. Homopolymerizations and copolymerizations proceed yielding materials with controlled molecular masses, and narrow molecular mass distributions. It is also demonstrated that this protocol is not limited to the use of TFE as a cosolvent and that additional halogenated alcohols, such as 2,2,2-trichloroethanol and 1,1,1,3,3,3-hexafluoroisopropanol are also effective cosolvents for the controlled polymerization of such cationic substrates. Finally, it is demonstrated that the TFE/methylene chloride mixture has no apparent detrimental effect on Grubbs' catalyst. © 2007 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 45: 2113–2128, 2007 相似文献