共查询到19条相似文献,搜索用时 125 毫秒
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高分子的自组装已成为当今高分子科学的热门研究课题之一[1] .开展该研究工作 ,首先要获得特定结构的聚合物 .我们设计合成如图 1所示的梳型聚合物 ,调节制备A ,B ,C三链段所用的单体和它们的聚合度等参数 ,并进一步进行自组装研究 .若A段是结晶聚合物 ,且熔融温度低于C段的玻璃化转变温度 ,则在定型储能材料等方面具有应用前景 .合成梳型嵌段聚合物有三个方法 ,即发散 (Graftfrom) ,收敛 (Graftto)和大分子方法 .采用大分子技术 ,每个梳型链长及支化密度可控 ,一直是人们青睐的方法[2 ] .一般采用与普通烯类单体共聚… 相似文献
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《高分子通报》2015,(10)
糖是生物体能量的主要来源,是参与生命活动过程的重要生物分子,人工合成侧链为糖分子的含糖聚合物,与天然多糖一样具有"糖簇效应",合成相对便利,引起越来越多的关注,癌细胞表面具有和糖分子特异性结合的蛋白,糖与癌症有着密切的联系,结合本课题组开展的工作本文介绍了对癌细胞具有较强亲和力的含糖聚合物材料的合成,以及所合成含糖聚合物材料在生物应用方面的一些研究进展。主要内容包括含糖聚合物材料的活性/可控自由基聚合和一锅法合成、与其它功能材料的复合、以及在生物模型、癌细胞靶向、癌细胞成像以及捕获等方面的应用。人工合成的含糖聚合物尤其是含糖聚合物复合材料展现出很好的生物性能,在生物医药方面具有广泛的应用前景。 相似文献
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从两二酸二乙酯、氯乙酸乙酯和氯苄出发,经LiAlH4还原,合成新的二元醇,进而合成新的螺环化合物:3,9-二羟乙基-3',9'-二苯甲基-1,5,7,11-四氧杂螺[5,5]十一烷.该化合物的结构由它的氢和碳-13核磁共振谱、红外光谱和元素分析得到证明.该单体在三氟化硼乙醚络合物的作用下进行开环聚合反应.由于环上四个取代基的稳定作用,聚合物的收率比较低(产率10%左右).通过对聚合物的结构分析,提出了这一单体的阳离子开环聚合反应机理.对随聚合温度升高,聚合物中酯基/苯基的克分子比降低,以及本体聚合时得到交联聚合物等一系列现象作了探讨. 相似文献
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Alaa S. Abd‐El‐Aziz Erin K. Todd Rawda M. Okasha Tabitha E. Wood 《Macromolecular rapid communications》2002,23(13):743-748
Polymers containing neutral and cationic iron moieties within and pendent to their backbones were prepared. The redox properties of the neutral and cationic iron centers were examined using cyclic voltammetry. Photolysis of the organometallic polymers led to decoordination of the cationic cyclopentadienyliron moieties from the polymer backbones. Glass transition temperatures of the resulting ferrocene‐based polymers were lower than those of the mixed neutral/cationic polymers. 相似文献
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基于原子转移自由基聚合技术的偶氮苯星形液晶聚合物的合成与表征 总被引:1,自引:0,他引:1
利用原子转移自由基聚合(ATRP)技术合成了含不同端基取代基的偶氮苯三臂星形侧链液晶聚合物. 均苯三酚与2-溴异丁酰溴通过酯化反应制备三官能团引发剂, 引发偶氮苯单体6-[4-(4-甲氧基苯基偶氮)酚氧基]己基甲基丙烯酸酯(MMAzo)或6-[4-(4-乙氧基苯基偶氮)酚氧基]己基甲基丙烯酸酯(EMAzo)的ATRP反应. 利用核磁共振氢谱(1H NMR)、凝胶色谱(GPC)、差示扫描量热法(DSC)和偏光显微镜(POM)等手段对星形聚合物进行表征. 星形聚合物的液晶性与相应均聚物相似, 但偶氮苯端基取代基的不同导致星形聚合物的液晶性差别显著. 在紫外/可见光照射下星形聚合物呈现明显的异构化转变. 相似文献
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Organoiron polynorbornene containing arylazo or hetarylazo dye chromophores has been prepared via ring opening metathesis polymerization using Grubbs' catalyst. The obtained polymers were isolated as brightly colored materials and displayed good solubility in polar organic solvents. The colors of these polymers were affected by the nature of the incorporated azo chromophores. Thermogravimetric analysis of these materials showed that the cleavage of the cyclopentadienyliron (CpFe+) moieties was between 225 and 231 °C, while the degradation of the polymer backbones occurred between 400 and 450 °C. UV-vis studies in DMF showed that the organoiron polymers containing arylazo dyes exhibit wavelength maxima around 425 nm. However, the replacement of these arylazo moieties with hetarylazo dyes displayed substantial bathochromic shifts in the λmax values (≈ 511 nm). 相似文献
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Multiblock polymers were prepared by combination of ATRP (CuBr/tris[(2‐pyridyl)methyl]amine) and RAFT polymerization involving cyclic trithiocarbonate (CTTC). In the combined polymerization system, the ATRP was introduced as constant radical source, CTTC underwent ring‐opening polymerization, and the incorporated trithiocarbonate moieties derived from CTTCs performed as RAFT agent. Through the integrated process, multiblock polymers containing predictable average block number together with controlled molecular weight of the blocks were prepared by one‐pot polymerization. The average block number of polymer was controlled by concentration ratio of CTTC to alkyl halide in ARTP, and the molecular weight of block were well regulated by concentration of CTTC and monomer conversion. © 2010 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 48: 2425–2429, 2010 相似文献
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Cristiam F. Santa Chalarca Todd Emrick 《Journal of polymer science. Part A, Polymer chemistry》2017,55(1):83-92
Sulfonium sulfonate, or sulfothetin, zwitterionic monomers were synthesized by ring‐opening of 1,3‐propanesultone with dialkyl sulfides containing styrenic or methacrylic moieties. Reversible addition‐fragmentation chain‐transfer polymerization of these monomers was achieved in water or trifluoroethanol, and the resulting polymers exhibited higher upper critical solution temperatures than the analogous sulfobetaine polymers. Unlike typical polymer zwitterions, these polymeric sulfothetins possess an inherent reactivity that proved tunable based on their chemical structures. This reactivity makes them amenable to post‐polymerization modification by nucleophilic dealkylation to rapidly access novel substituted polymers and gels. © 2016 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2017 , 55, 83–92 相似文献
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Atsushi Izumi Masahiro Teraguchi Ryoji Nomura Toshio Masuda 《Journal of polymer science. Part A, Polymer chemistry》2000,38(7):1057-1063
Poly(phenylenevinylene)‐based conjugated polymers with azobenzene groups in the main chains were prepared by the Pd‐catalyzed coupling polymerization of divinylarenes with dihaloarenes. The Pd‐catalyzed coupling polymerization of 4,4′‐divinylazobenzene with dihaloarenes such as 1,3‐dibromobenzene, 1,4‐dibromo‐2,5‐dihexylbenzene, 4,4′‐dibromoazobenzene, and 4,4′‐diiodoazobenzene resulted in polymers with poor solubility. In contrast, soluble polymers containing azobenzene moieties in the main chains were attainable from divinylbenzenes with 4,4′‐dihaloazobenzenes if either or both of the monomers possessed hexyl groups on the aromatic rings. The number‐average molecular weight of the polymer exceeded 10,000 under optimized conditions, and the polymer showed a remarkably redshifted absorption in the visible region (456 nm). 1H NMR and IR spectra supported that the polymers having only trans‐geometry for the double bonds. © 2000 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 38: 1057–1063, 2000 相似文献
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N. Inagaki S. Tasaka Y. Horikawa 《Journal of polymer science. Part A, Polymer chemistry》1989,27(10):3495-3501
Plasma polymerization of perfluorobenzene/sulfur dioxide (PFB/SO2) mixture was investigated by elemental analysis, infrared spectroscopy, and XPS. Plasma polymer films like Nafion were obtained from the plasma polymerization of PFB/SO2 mixture. The plasma polymerization deposited fluoropolymers with sulfur moieties including sulfonate and sulfonic acid groups. The elemental composition, F/C, and S/C atomic ratio of the formed plasma polymers were 0.65–0.67 and 0.24–0.27, respectively, which were independent of the starting mixture composition. The polymers showed cation-exchange ability of which the capacity was 0.49 meq/g polymer, and initiated the polymerization of pyrrole. 相似文献
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Dong‐Gyun Kim Hae‐Sung Sohn Sung‐Kon Kim Aeri Lee Jong‐Chan Lee 《Journal of polymer science. Part A, Polymer chemistry》2012,50(17):3618-3627
A series of organic/inorganic hybrid star‐shaped polymers were synthesized by atom transfer radical polymerization using 3‐(3,5,7,9,11,13,15‐heptacyclohexyl‐pentacyclo[9.5.1.13,9.15,15.17,13]‐octasiloxane‐1‐yl)propyl methacrylate (MA‐POSS) and poly(ethylene glycol) methyl ether methacrylate (PEGMA) as monomers and octakis(2‐bromo‐2‐methylpropionoxypropyldimethylsiloxy)octasilsesquioxane as an initiator. Star‐shaped polymers with methyl methacrylate (MMA) and PEGMA moieties were also prepared for comparison purposes. Dimensionally stable freestanding film could be obtained from the hybrid star‐shaped polymer containing 26 wt % of MA‐POSS moieties although its glass transition temperature is very low, ?60.9 °C. As a result, the hybrid star‐shaped polymer electrolyte containing lithium bis(trifluoromethanesulfonyl)imide showed ionic conductivities (1.75 × 10?5 S/cm at 30 °C), which were two orders of magnitude higher than those of the star‐shaped polymer electrolyte with MMA moieties. © 2012 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2012 相似文献
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Xinde Tang Longcheng Gao Nianfeng Han Xinghe Fan Qifeng Zhou 《Journal of polymer science. Part A, Polymer chemistry》2007,45(15):3342-3348
4‐Arm star side‐chain liquid crystalline (LC) polymers containing azobenzene with different terminal substituents were synthesized by atom transfer radical polymerization (ATRP). Tetrafunctional initiator prepared by the esterification between pentaerythritol and 2‐bromoisobutyryl bromide was utilized to initiate the polymerization of 6‐[4‐(4‐methoxyphenylazo)phenoxy]hexyl methacrylate (MMAzo) and 6‐[4‐(4‐ethoxyphenylazo)phenoxy]hexyl methacrylate (EMAzo), respectively. The 4‐arm star side‐chain LC polymer with p‐methoxyazobenzene moieties exhibits a smectic and a nematic phase, while that with p‐ethoxyazobenzene moieties shows only a nematic phase, which derives of different terminal substituents. The star polymers have similar LC behavior to the corresponding linear homopolymers, whereas transition temperatures decrease slightly. Both star polymers show photoresponsive isomerization under the irradiation with UV–vis light. © 2007 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 45: 3342–3348, 2007 相似文献