两亲性超支化聚合物的研究进展

两亲性超支化聚合物作为一种新型功能性材料.近年来引起了人们的广泛关注.两亲性超支化聚合物的合成丰要是利用不同亲水性的链段对超支化聚合物端基进行改性,或者首先在超支化聚合物末端产生活性位点,再利用超支化分f作为大分子引发剂引发烯类单体进行斤环聚合、原子转移自由基聚合等得到以超支化聚合物为核的两亲性超支化共聚物;这些分子由...     

不饱和端基超支化聚合物/丙烯酸酯共聚乳液的研究

利用Si—H加成反应制得了以CC为端基的超支化含硅聚合物,并将其与丙烯酸酯类单体进行乳液共聚,对聚合反应机理及所得聚合物的性能进行了测试分析.结果表明,含有大量CC端基的超支化含硅聚合物能与丙烯酸酯类单体稳定聚合,制得了平均粒径小于100nm高度交联的乳胶粒子.共聚物的红外光谱证实,超支化聚合物的不饱和端基已全部反应,形成了以超支化聚合物为多臂交联点的交联型乳胶粒子.随聚合体系中超支化聚合物用量的增加,乳液聚合反应速率增大,乳胶粒粒径减小,共聚物热稳定性显著提高.     

新型功能性超支化聚酯的合成及表征

近年来 ,树枝状和超支化聚合物的研究受到了广泛重视 ,被视为 2 1世纪聚合物科学发展的重要方向[1] .这两种聚合物都有大量的端基 ,与相同分子量的线型聚合物相比 ,它们具有更低的粘度和更好的溶解性 .树枝状聚合物具有规整的结构 ,但合成困难 ;超支化聚合物的支化结构不完整 ,可以通过简单的一步聚合获得 ,因此 ,后者受到更广泛的重视 ,也最有可能实现工业化 [2 ,3] .通常 ,超支化聚合物是通过 ABx(x≥ 2 )型单体的缩聚合成的 ,通过改变超支化聚合物的组成、结构及对其端基进行功能修饰 ,可以制备多种具有特殊用途的新材料 ,在粘度改性剂…     

超支化/星型双亲性聚合物作为药物载体研究新进展

双亲性聚合物是一类既具有良好的亲水性质,又具有疏水性质的聚合物,作为药物载体有很好的应用潜力。由于超支化聚合物及星型聚合物具有独特的拓扑结构,分子内存在空腔,可以包埋更多的药物,并且聚合物含有丰富的端基官能团,可以将较多的亲水基团引入端基,使其与体液有更好的相容性,所以超支化/星型聚合物作为药物载体已经成为研究的热点。本文综述了近些年来超支化/星型双亲性聚合物应用在药物传导领域的研究状况,重点介绍了超支化聚合物和星型聚合物载药体系,包括超支化聚甘油药物载体和含聚己内酯的星型聚合物药物载体。对聚合物作为药物载体所涉及的负载与释放方式进行了总结。     

重氮偶合反应合成超支化偶氮聚合物的光响应性能研究

利用重氮偶合反应和后重氮偶合反应制备了主链和端基含有不同假芪型偶氮苯生色团的超支化偶氮聚合物.利用氢核磁共振、紫外光谱、红外光谱等分析手段确定了合成聚合物的结构、玻璃化转变温度和光谱特性等.研究了聚合物光致二向色性的性能,此聚合物的取向有序度为0.063.用两束相干的P偏振Ar+激光对聚合物膜进行光加工,得到形状规则的正弦波形表面起伏光栅,末端偶氮苯基团的引入极大地增加了超支化偶氮聚合物的光响应速度.     

超支化聚合物研究进展

超支化聚合物由于具有高度文化三维球状结构以及众多的端基,因此显示出与相应线型分子截然不同的性质,如低粘度、无链缠结和良好的溶解性.本文讨论了超支化聚合物的特性与表征,对合成超支化聚合物所用单体以及产物作了详细介绍,旨在引起对该领域的兴趣.     

全共轭型二茂铁基聚合物

由于二茂铁独特的夹心结构使含二茂铁基聚合物具有独特的电、磁、催化以及氧化还原性能。全共轭型二茂铁基聚合物由于其特殊的π-π电子结构,使其在电学、光学等方面的表现出优越的性质。本文从3个方面（主链型、侧链型和超支化型）介绍了近年来含有二茂铁基团全共轭聚合物的合成及其性能方面的研究进展,讨论了聚合物的结构对溶解性、氧化还原性等方面的影响,并探讨了这一领域存在的问题及可能的发展方向。     

两亲性全季铵盐超支化聚合物的设计与合成及主-客体超分子着色应用研究

采用高效的巯基-炔点击化学与Menschutkin季铵化反应,合成了一种带有1个叠氮基、2个炔基和2个季铵盐基团的AB2型季铵盐单体,通过核磁共振、红外光谱、质谱等方法对单体结构进行了确认.将所得单体进行点击聚合,得到全季铵盐超支化聚合物,并用端叠氮基的长链烷烃封端,得到核亲水-壳憎水的两亲性超支化聚季铵盐.研究所得两亲性超支化聚合物对染料的装载性能,结果表明所合成的带正电荷两亲性聚合物对多种带负电荷的水性染料装载效果好,平均相转移率高达95%.进一步将装载染料的主-客体超分子复合物用于聚合物制品着色,发现其对SBS及PMMA等聚合物有很好的着色效果,着色均匀且不掉色,着色的膜色泽鲜艳透明.     

超支化/星形聚合物电解质的研究进展

与液体电解质相比较,聚合物电解质以其易加工、设计灵活、质量轻、安全无毒的特点而受到人们的广泛关注,具有取代液态电解质的潜在应用价值,而超支化/星形聚合物以其无定形、低玻璃化转变温度、支化结构等特点可被用于固态电解质。本文综述了超支化/星形聚合物电解质材料的研究进展,重点介绍了超支化/星形聚合物基电解质和超支化/星形聚合物共混基电解质,并对超支化/星形聚合物单一离子导体在锂离子电池方面的应用前景作了概述。     

端基结构对超支化聚合物静电吸附自组装行为的影响

研究了3种具有相同骨架结构、不同端基的超支化聚合物与线型聚阳离子(PDAC)的静电吸附自组装.结果表明,超支化聚合物的组装过程与线型弱酸聚合物相似,都受溶液pH值与无机盐浓度的影响,但影响程度随端基结构不同而变化.此外,对以超支化聚合物为最外层的不同自组装膜的表面形貌及接触角进行了表征,其表面形貌及亲水性随端基结构的不同而不同.     

α-Amino acid derived enaminones and their application in the synthesis of N-protected methyl 5-substituted-4-hydroxypyrrole-3-carboxylates and other heterocycles

A new and simple synthesis of novel N-protected methyl 5-substituted-4-hydroxypyrrole-3-carboxylates, which exist in equilibrium with their 4-oxo tautomers, has been developed in two steps starting from N-protected α-amino acids. The key intermediates are enaminones, which can also be isolated, characterized, and used for the construction of other functionalized heterocycles, before they spontaneously decompose to pyrrole products. 4-Hydroxypyrroles are prone to partial aerial oxidation but can be efficiently alkylated or reduced to stable polysubstituted pyrrolidine derivatives.     

Specific intramolecular aromatic CH insertion of diazosulfonamides

The chemoselectivity in the intramolecular CH insertion of various diazosulfonamides has been experimentally studied. The results reveal that the aliphatic 1,4-, 1,5-, or 1,6-C(sp³)?H insertions of diazosulfonamides are not accessible, while the aromatic 1,5-C(sp²)?H insertion can be realized specifically by adjusting the diazo-adjacent group. In addition, the general chemoselectivities in the intramolecular CH insertions of diazosulfonyl compounds are summarized. Generally, diazosulfones undergo both aromatic 1,5-C(sp²)?H and aliphatic 1,5- and 1,6-C(sp³)?H insertions, while diazosulfonates undergo aliphatic 1,5- and 1,6-C(sp³)?H insertions. However, diazosulfonamides only undergo aromatic 1,5-C(sp²)?H insertion.     

N-Heterocyclic carbene-palladacyclic complexes: synthesis,characterization and their applications in the C-N coupling and α-arylation of ketones using aryl chlorides

N-Heterocyclic carbene-palladacyclic complexes 3 were successfully achieved in a one-pot procedure under mild conditions. The structure of 3a was unambiguously confirmed by X-ray single crystal diffraction and it was an active catalyst in the Buchwald-Hartwig amination and α-arylation of ketones even at very low catalyst loadings (0.01?mol%).     

Iodine-mediated oxidative Pictet-Spengler reaction using terminal alkyne as the 2-oxoaldehyde surrogate for the synthesis of 1-aroyl-β-carbolines and fused-nitrogen heterocycles

An efficient iodine-mediated oxidative Pictet-Spengler reaction in dimethyl sulphoxide (DMSO) using terminal alkynes as the 2-oxoaldehyde surrogate for the synthesis of aryl (9H-pyrido[3,4-b]indol-1-yl)methanones is described. The scope of the protocol includes the total synthesis of Fascaplysin, Eudistomins Y₁ and Y₂. The methodology is extended for preparing pyrrolo[1,2-a]-quinoxaline and indolo[1,5-a]quinoxaline derivatives. The utility of 1-aroyl-β-carbolines was demonstrated by performing palladium-catalyzed β-carboline directed ortho-C(sp2)-H functionalization of the phenyl ring with thiomethyl (SMe) group using DMSO as source and for accessing 4-aryl-canthin-6-ones.     

Facile synthesis of bicyclic 1-arylpyrazol-5-ones

In this Letter, we described a facile method for constructing fused bicyclic 1-arylpyrazol-5-one ring system. We employed various methylene-containing carboxylic acids as the substrates and proved that the pyrazolone ring closure requires activated methylene group in intermediate II. Accordingly, a series of structurally diversified, fused bicyclic 1-arylpyrazol-5-ones was prepared in moderate to high yields using the requisite substrates.     

Synthesis of pyrrolo[1,2-a]pyrazines and pyrazino[1,2-a]indoles by Curtius reaction in Morita-Baylis-Hillman derivatives

Synthesis of substituted pyrrolo[1,2-a]pyrazines and pyrazino[1,2-a]indoles from the Morita-Baylis-Hillman derivatives of acrylates via saponification followed by Curtius reaction is described.     

正丁胺对激光染料荧光谱影响的研究

用正丁胺作为碳源,采用射频辉光放电制备碳膜,选用激光染料R6G和聚乙二醇混合液作为蒸气源,采用单源热蒸发,在蒸发室与染料同时沉积得到混合膜,用拉曼光谱和红外光谱分析了碳膜的结构和键合方式,分析表明:碳膜中存在胺基团和氢原子.混合膜的荧光谱测量结果表明,认为正丁胺对染料荧光谱的影响是因为胺基和氢原子的存在.     

Cu0-catalysed 1,3-dipolar cycloadditions of α-amino acid derived N,N-cyclic azomethine imines to ynones

A series of 20 CuAIAC reactions between eight 4-acylamino substituted pyrazolidine-3-one-1-azomethine imines and four terminal ynones were performed using Cu⁰ as catalyst. The corresponding fluorescent cycloadducts were obtained in very high yields upon simple workup. Thus, Cu-metal turned out to be a better catalyst than Cu^I in terms of yield and ease of isolation. Availability of azomethine imines, mild reaction conditions, and simple workup enable a “click” access to libraries of densely substituted 2,3-dihydro-1H,5H-pyrazolo[1,2-a]pyrazol-1-ones. Reactivity of differently substituted dipoles was evaluated experimentally and by quantum chemical methods (DFT).     

Synthesis and antioxidative/anti-inflammatory activity of novel fullerene–polyamine conjugates

(E)-4-(Fullerenopyrrolidin-1-yl)-3-methylbut-2-enoic acid and its corresponding succinimidyl ester, readily obtained through Prato-type modification of C₆₀, were used for the selective N-acylation of polyamines. The thus obtained conjugates were evaluated for their antioxidative and anti-inflammatory activity and their cytotoxicity was determined. Members of this family of compounds showed interesting anti-lipid peroxidation, anti-lipoxygenase and anti-inflammatory activity and comparable cytocompatibility to spermidine.