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1.
新型超支化聚芳酰胺的合成及表征   总被引:3,自引:0,他引:3  
于世钧  赵洪霞  李悦生 《化学通报》2003,66(12):843-846,820
以3,5—二硝基苯甲酰氯和对氨基苯甲酸为原料,经两步反应合成了新型AB2型单体4—(3,5-二氨基苯甲酰氨基)苯甲酸。在溶液中通过自缩聚反应合成了新型超支化聚芳酰胺,将其活性端氨基与酰氯反应,经原位改性合成了五种封端的超支化聚芳酰胺,并利用IR、^1HNMR、DSC及TG等方法对所合成的六种新型超支化聚合物的结构和性能进行了表征与测试。  相似文献   

2.
超支化聚(酯-酰胺)的合成与流变改性研究   总被引:10,自引:0,他引:10  
近十几年来 ,超支化聚合物因具有独特的结构和特殊的性能而受到普遍关注[1] .超支化聚合物具有低的熔体粘度 ,与线性聚合物共混可显著改善其加工流变性 ,具有商业应用潜力 .关于超支化聚合物在流变改性方面的应用已有文献报道[2~ 6] ,但目前文献中的大多数单体合成较繁琐且收率不高 ,这已成为制约超支化聚合物应用的瓶颈 ,如何以简便的途径合成超支化聚合物已成为当前研究的重点 .本文设计一条新的合成路线 ,即以 1 ,2 ,4 苯三酸酐、乙醇胺及乙酸酐为原料 ,以高的收率得到了单体N ( 2 乙酰氧基乙基 ) N ( 2′ ,4′ 二羧基苯甲酰基 )胺 (…  相似文献   

3.
1,4-双{2-[4-[2-苯并恶唑)苯基]乙烯基}苯及衍生物的合成   总被引:4,自引:0,他引:4  
张田林  吴亚明 《有机化学》2003,23(4):350-352
通过Wittig-Horner反应,以对苯二甲醛和2—(4-氯甲基苯基)苯并恶唑为主要 原料,合成了八个新型1,4-双{2-[4-(2—苯并恶唑)苯基]乙烯基}苯及衍生物.通 过IR,^1H NMR,UV-vis和元素分析等方法确认了它们的化学结构,分析数据表明各 标题化合物分子结构中的C=C双键均为反式结构特.  相似文献   

4.
超支化聚(胺酯)的分子设计及其制备   总被引:21,自引:1,他引:21  
以丙烯酸甲酯和二乙醇胺为原料由Michael加成反应制得N ,N 二羟乙基 3 胺基丙酸甲酯单体 ,再用“准一步法”和“发散法”使之与 1 ,1 ,1 三羟甲基丙烷 (核 )反应合成一种新型超支化聚 (胺 酯 ) .以核磁共振和元素分析方法对N ,N 二羟乙基 3 胺基丙酸甲酯单体的分子结构进行了表征 .GPC测定表明合成的超支化聚 (胺 酯 )分子量分布窄 ,具有单分散性 ;粘度小于同分子量的线形分子 ;耐热性能较好 ,失重温度高于2 0 0℃ .  相似文献   

5.
利用A2/B3单体通过重氮偶合反应制备了超支化偶氮聚合物.利用核磁共振、红外光谱、紫外光谱和DSC热分析手段表征了聚合物的结构、光谱性能和玻璃化转变温度.合成的超支化偶氮聚合物具有很好的光响应性能,用488nm Ar+激光对超支化偶氮聚合物薄膜进行光加工,得到了规则的表面起伏光栅.  相似文献   

6.
合成了一系列含羟基和乙酰氧基的超支化聚酯,将4',4'二羟基-2-甲酸-三 苯基甲烷(酚酞啉)直接缩聚和将4~',4~"-二羟基-2-甲酸-三苯基甲烷进行酯 交换反应都成功得到了超支化聚酯,以PS作标准物,由GPC测得的重均分子量为 2000到8000,~13C NMR测试表明聚合物支化度略高于50%,聚酯的玻璃化转变温度 依赖于末端和侧基官能团类型,该超支化聚酯末端含有反应性官能团,具有类似线 性高分子的高的热稳定性,相比之下,由于其大分子的形状和官能团的影响,末端 为乙酰氧基的超支化聚枉费显示了优良的溶解性能,这与一般线性高分子大不相同 ,由于氢键的存在,末端为羟基的超支化聚酯的溶解性能不佳,但是酸酯显示了 优良的溶解性能,这与一般线性高分子大不相同,由于氢键的存在,末端为羟基的 超支化聚枉费的溶解性能不佳,但是酸化可破坏氢键网络,得到的超支化聚酯可深 于一般有机溶剂。  相似文献   

7.
设计并通过原子转移自由基聚合方法 (ATRP)合成了核壳型多羟基多臂星状超支化聚合物刷 .以 2 溴异丁基酰溴封端的超支化聚 (3 乙基 3 羟甲基氧杂环丁烷 ) (HP Br)作为大分子引发剂 ,采用Cu(I)Br和N ,N ,N′ ,N′ ,N″ 五甲基二乙基三胺 (PMDETA)催化体系 ,在丁酮与丙醇的混和溶液中 ,通过甲基丙烯酸羟乙酯(HEMA)的ATRP溶液聚合 ,得到了一系列含有大量羟基的多臂星状超支化聚合物刷 (HP g PHEMA) ,并考察了其羟基的活性 ,发现羟基还可以与苯甲酰氯发生反应 .产物的结构和热性能用1 H NMR、FTIR、GPC、TGA、DSC等进行了表征和测试 .  相似文献   

8.
近年来,颜德岳等基于A2型单体二丙烯酸酯及BB2′型单体二胺化合物合成了多种端胺基超支化聚(酯-胺),并对反应机理及聚合物结构进行了系统研究[1,2],结果表明,由于B与B′活性差异,反应首先生成AB2′型和B4′型中间体,进一步聚合得到可溶性产物.我们基于A3型单体三丙烯酸酯与B2型单体二胺化合物合成了端丙烯酸酯基超支化聚(酯-胺)[3,4].在这些体系中,由于官能团反应活性高,难以控制反应程度.另外,由于超支化聚合物不能直接用作结构材料,其在涂料、粘合剂等领域的应用多基于末端官能团的固化反应[5].但通常由于官能团在分子表面密集分布,部…  相似文献   

9.
利用溶液聚合方法,以4,4′-二胺基二苯甲烷与氨三乙酸为原料,制备了A2+B3型超支化半芳香型聚酰胺(HPMDA),讨论了反应温度、反应时间、芳香二胺与氨三乙酸单体比例、单体浓度、催化剂及活化剂对反应的影响,发现了临界凝胶条件。利用傅立叶变换红外光谱(FTIR)、1H核磁共振谱(1HNMR)对制备的超支化半芳香型聚酰胺进行了结构表征。用乌式粘度计、热重分析(TG)测定了超支化半芳香型聚酰胺的粘度和热稳定性,并从微观反应机理和拓扑结构的角度,研究了反应条件对聚合物特性粘度的影响。  相似文献   

10.
端丙烯酸酯基超支化聚(酯-胺)的结构分析及光固化   总被引:2,自引:1,他引:1  
近年来 ,具有树枝状结构的超支化聚合物因其独特的物理化学性质而得到广泛关注[1,2 ] .超支化聚合物主要采用 3种途径合成 ,( 1 )ABn(n >2 )型及潜ABn 型单体的聚合 ;( 2 )由A2 与Bn 型单体直接聚合 ;( 3)先由特定的单体对原位形成ABn型中间体后再聚合 .其中后两种方法可直接采用商业化原料 ,因此更具有实用价值 .目前 ,基于途径 ( 2 )已合成出超支化聚酰胺[3 ] 、聚醚[4] 、聚酰亚胺[5] 和共轭聚合物[6] 等 ,但该途径容易生成凝胶化产物 ,通过控制反应物浓度、在凝胶点之前停止反应等 ,可得到溶解型超支化产物 .由于超支化聚合物具有低…  相似文献   

11.
This paper describes postgrafting of hyperbranched dendritic polyamidoamine initiated from terminal amino groups of polymer chains grafted onto ultrafine silica surface in order to modify the silica surface. Surface grafting of polymer having terminal amino groups as initiator sites was performed by a reaction of terminal diamine-type polyoxyethylene with epoxy groups previously introduced onto the surface by 3-glycidoxypropyltri-methoxysilane treatment. The postgrafting reaction of dendritic polyamidoamine from the terminal amino groups was achieved by repeating the Michael addition of methyl acrylate to amino groups followed by amidation of the resulting ester moieties with ethylenediamine or hexamethylenediamine. Both the amount of amino groups and the percentage of postgrafting of the resulting polyamidoamine increased with an increase in the number of generations: the amino group content increased from 0.40 mmol/g to 2.68 mmol/g, and the percentage of postgrafting reached 61.0% after the 12th generation by using ethylenediamine in amidation. These values, however, were considerably smaller than the theoretical values. This indicates that the postgrafted polyamidoamine was a hyperbranched polymer but not a precise dendrimer. Ethylenediamine as a reactant in amidation was more effective than hexamethylenediamine, and a low content of initial amino groups was also preferred to a large amount of them probably because of steric hindrance in the propagation of hyperbranched dendritic polyamidoamine. The average particle size of hyperbranched dendritic polyamido-amine-postgrafted silica measured by light scattering photometry increased with an increase in the number of generations of the resulting polyamidoamine.  相似文献   

12.
Luminescent polymer materials have gained considerable research efforts in the past decades and are generally molecular designed by extending the π system of the polymer main chain or by incorporating chromophores into the polymer chain, which suffer from poor solubility, difficult synthesis, or multi-step procedures. Meanwhile, according to the step-growth polymerization theory, synthesis of hyperbranched polymers from an AB-type monomer is still challenging. Herein, we report a one-pot synthesis of nonconjugated luminescent hyperbranched polymer material via Barbier hyperbranching polymerization-induced emission (PIE) from an AB-type monomer. The key step in the realization of the hyperbranched polymer is bi-functionalization of a mono-functional group. Through a Barbier reaction between an organohalide and an ester group in one pot, bi-functionalization of mono-functional ester is realized through two-step nucleophilic additions, resulting in hyperbranched polytriphenylmethanols (HPTPM). Attributed to through-space conjugation and inter- and intramolecular charge-transfer effects induced by polymer chain, nonconjugated HPTPMs are PIEgens, which are tunable by monomer structure and polymerization time. When all phenyl groups are rotatable, HPTPM is aggregation-induced emission type PIEgen. Whereas, it is aggregation-caused quenching type PIEgen if some phenyl groups are rotation forbidden. Further potential applications of PIEgen are in the fields of explosive detection and artificial light harvesting systems. This work, therefore, expands the monomer library and molecular design library of hyperbranched polymers through “bi-functionalization of mono-functional group” strategy, which eventually expands the preparation library of nonconjugated luminescent polymer materials through one-pot PIE from nonemissive monomer.  相似文献   

13.
The influence of hyperbranched polyesters with different functional end groups on the surface tension of mixtures with an oligo(ester diol) was investigated. The temperature dependence of the surface tension of the pure components and of the mixtures was measured by a modified Wilhelmy balance technique. The results indicate that the surface tension of the pure hyperbranched polyesters strongly depends on the functionality of the end groups. The functionalization of the hydroxyl end groups by short alkyl chains (methyl, tert-butyl) reduced the surface tension depending on the degree of substitution. The surface tension of the mixtures with the hydroxyl-terminated hyperbranched polyester was slightly increased at higher concentrations of the hyperbranched polymer compared to the surface tension of the pure ester diol. On the other hand, the surface tension of mixtures could be considerably decreased using 1% of hyperbranched polyester polyols partially substituted with short alkyl chains. In that case, the modified hyperbranched polyesters act as surface active agents. On the molecular level, the enrichment of the modified hyperbranched polyester in the surface region was proven by X-ray photoelectron spectroscopy measurements.  相似文献   

14.
可光固化超支化聚硅氧基硅烷的合成与表征   总被引:1,自引:0,他引:1  
自20世纪80年代末期Kim和Webster首次采用AB2型单体合成超支化聚合物以来,超支化聚合物以其新颖的结构、独特的性能和广泛的应用前景受到了科学界和工业界的广泛关注.其中超支化有机硅聚合物,尤其是硅氧基聚合物,由于具有良好的高低温稳定性、耐腐蚀性、耐候性等,以及硅氯、硅氢等末端基团易于功能化改性的特点,使其在功能性涂层材料、催化剂以及液晶材料等领域具有重要的应用价值.到目前为止,有关超支化聚硅氧基硅烷的研究主要集中在AB2型单体(x≥2,A和B分别为硅氢基团和乙烯基、烯丙基等不饱和基团)的制备以及硅氢加成产物的功能化改性方面.  相似文献   

15.
The synthesis and characterization of hyperbranched aromatic poly(ether imide)s are described. An AB2 monomer, which contained a pair of phenolic groups and an aryl fluoro moiety activated toward displacement by the attached imide heterocyclic ring, was prepared. The nucleophilic substitution of the fluoride with the phenolate groups led to the formation of an ether linkage and, subsequently, to the hyperbranched poly(ether imide), which contained terminal phenolic groups. A similar one‐step polymerization involving a monomer that contained silyl‐protected phenols yielded a hyperbranched poly(ether imide) with terminal silylated phenols. The degree of branching of these hyperbranched polymers was approximately 55%, as determined by a combination of model compound studies and 1H NMR integration experiments. End‐capping reactions of the terminal phenolic groups were readily accomplished with a variety of acid chlorides and acid anhydrides. The nature of the chain‐end groups significantly influenced physical properties, such as the glass‐transition temperature and the solubility of the hyperbranched poly(ether imide)s. As the length of the acyl chain of the terminal ester groups increased, the glass‐transition temperature value for the polymer decreased, and the solubility of the polymer in polar solvents was reduced, becoming more soluble in nonpolar solvents. © 2001 John Wiley & Sons, Inc. J Polym Sci Part A: Polym Chem 39: 2536–2546, 2001  相似文献   

16.
We synthesized an AB2‐type monomer, 4‐{4‐[di(4‐aminophenyl)methyl]phenoxy}phthalic acid, which contained one phthalic acid group and two aminophenyl functionalities. The direct self‐polycondensation of the AB2‐type monomer in the presence of triphenylphosphite as an activator afforded a hyperbranched poly(ether imide) with a large number of terminal amino groups. This polymer was characterized with 1H NMR and IR spectroscopy. The degree of branching of the hyperbranched poly(ether imide) was approximately 56%, as determined by a combination of model compound studies and an analysis of 1H NMR spectroscopy integration data. The terminal amino groups underwent functionalization readily. The solubility and thermal properties of the resulting polymers depended on the nature of the chain end groups. In addition, the hyperbranched poly(ether imide) was grafted with polyhedral oligomeric silsesquioxane (POSS). Transmission electron microscopy analysis revealed that the grafted POSS molecules aggregated to form a nanocomposite material. © 2003 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 41: 3726–3735, 2003  相似文献   

17.
In this contribution, we present new reduction‐cleavable hyperbranched disulfide bonds‐containing poly(ester triazole)s with limited intramolecular cyclization, which can be synthesized by the Cu(I)‐catalyzed azide–alkyne cycloaddition (CuAAC) of A2 monomer of dipropargyl 3,3′‐dithiobispropionate and B3 monomer of tris(hydroxymethyl)ethane tri(4‐azidobutanoate). The hyperbranched poly(ester triazole)s possess numerous terminal groups and weight‐average molecular weight up to 20,400 g mol?1 with a polydispersity index in the range 1.57–2.17. The CuAAC introduces rigid triazole units into the backbones of hyperbranched poly(ester triazole)s and reduces intramolecular cyclization, which is proved by topological analysis and 1H NMR spectroscopy. The disulfide bonds on backbones endow the reduction‐cleavable feature to the hyperbranched poly(ester triazole)s at the presence of dithiothreitol. It gives a novel and convenient methodology for the synthesis of reduction‐responsive functional polymer with controlled topologies, and the reduction‐cleavable hyperbranched poly(ester triazole)s with limited intramolecular cyclization are expected to possess potential in the application of stimuli‐responsive anticancer drug nanocarriers. © 2015 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2015 , 53, 2374–2380  相似文献   

18.
The conjugation of PAMAM dendrimer and folic acid is a well‐studied multivalent targeted drug delivery system, but it is expensive and difficult to be synthesized. To construct an inexpensive and well‐defined multivalent targeted drug delivery system, a cheap carrier — Boltorn® series hyperbranched aliphatic polyester — was proposed as the nanodevice to carry fluorescein, folic acid, and methotrexate. The construction follows a facile route: (1) synthesizing the carrier — a hybrid hyperbranched polymer with acyclic hydroxyls and cyclic carbonate, (2) linking fluorescein to the hyperbranched polymer via the acyclic hydroxyls, (3) opening the ring of the cyclic carbonate with the amino group of folic acid, and (4) attaching the drug methotrexate to the resulting hydroxyls by ring‐opening reaction. In this route, the peripheral hydroxyls of the hyperbranched polymer are divided into two groups and reacted with three reagents in sequence to form the desired multivalent targeted drug delivery system. Copyright © 2009 John Wiley & Sons, Ltd.  相似文献   

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