用电子吸收光谱和荧光光谱研究芳胺引发的光聚合机理

用紫外吸收光谱和荧光光谱分析了苯胺等芳胺引发光聚合的聚丙烯腈和聚甲基丙烯酸甲酯的端基,认为一级胺引发的聚合物端基为二级胺,二级胺引发的聚合物端基为三级胺,从而表明,一级芳胺和二级芳胺在光照下与烯类单体相互作用产生氮自由基引发聚合。     

聚苯基喹(口恶)啉

一、前言 1967年Hergenrother等公开报道了聚苯基喹噁啉(PPQ)。PPQ是聚喹噁啉中吡嗪环上的氢被苯基取代的一类芳杂环高聚物,是由芳香族双(邻-二胺简称四胺)和苯基取代的双(α-二羰基)化合物(简称四酮)缩聚而制得。 PPQ是苯基化芳杂环高聚物中最引人注目的一类,苯基引入后不仅大大改进了聚喹噁啉类高聚物的热氧化稳定性,提高了耐温等级。而且,四酮单体制备方便,易和四胺缩聚,聚合物的溶解度和聚合物溶     

二氮杂二环[n30]衍生物的合成及结构表征

对氟苯甲酰基或杂环芳酰基取代的杂环烯酮缩胺1(2)与溴乙酸乙酯反应,高产率地得到二氮杂二环[330]4或二氮杂二环[430]5衍生物。文中讨论了合成反应机理,并且对产物的结构进行了表征。研究结果提供了一种高效率合成氮杂稠环化合物的方法,产率：79％-84％。     

四氮唑类杂环化合物的研究进展

氮杂环化合物是一类具有重要应用价值和良好生物活性的化合物,在生物、医药、农药等领域的应用非常广泛,一直是人们研究的热点,四氮唑类杂环化合物又是其中的一类重要五元芳杂环化合物。因其在医药上取得广泛的应用引起人们越来越多的关注。文章对杂环化合物、氮杂环化合物的发展进行了简单的叙述,并对不同种类四氮唑芳杂环化合物的发展及其应用做了详细阐述。     

新型吡啶基聚氨酯脲弹性体的热机械性能与介电性能

正吡啶及其衍生物是生物体系中重要的杂环化合物,是维生素B或植物中产生的生物碱中的结构元素。吡啶衍生物可用于农业、医药和其他行业。吡啶在六元芳环上具有氮杂环结构,其衍生物在杂环化学领域具有重要作用。许多天然产物中都发现有吡啶衍生物,但对于聚合物化学来说,则是通过不同方法合成了许多具有吡啶部分的化合物。基于吡啶的性质,对刚性吡啶杂环及其衍生物掺入聚合物基质进行了研究。吡啶环可以改善热稳定性和化学稳定性,保持高温下的机械性能,并改善电学和介电性能。因此获得了新型可     

聚双马来酰亚胺—芳胺树脂的试制

由于尖端科学,宇航技术,电机电器及其它现代化工业部门对耐高温聚合物的需要日益增长,六十年代以来,芳杂环聚合物得到了迅速的发展。聚酰亚胺是耐高温芳杂环聚合物中最早工业化的一个品种,因为它具有耐高温、高绝缘、耐辐射、耐磨等许多优异的性能,所以用途不断扩大。但是均苯型聚酰亚胺由于不溶不熔,加工困难,因此应用受到一定限制。 为了改进均苯聚酰亚胺的加工性能,国     

新型含氮杂环丁烷阳离子水性聚氨酯的合成

介绍了一种全新的氮杂环丁烷季铵离子作为亲水基团的阳离子水性聚氨酯分散体的合成。采用二异丙醇胺与环氧氯丙烷反应合成缩水甘油基二异丙醇胺,缩水甘油基二异丙醇胺作为扩链剂与聚氨酯预聚体反应而后酸化,将引入聚氨酯结构的缩水甘油胺异构化为氮杂环丁烷季铵离子;然后将含有氮杂环丁烷季铵离子的聚氨酯预聚体分散于水中获得阳离子水性聚氨酯分散体。新型含氮杂环丁烷阳离子水性聚氨酯因其离子性以及氮杂环丁烷的反应活性,在木器封底涂层、纺织整理、蛋白胶交联剂等方面具有潜在的应用前景。     

烯烃的氮杂环丙化和C-H键胺化的研究进展

文章综述了通过烯烃的氮杂环丙化和C-H键的酰胺化制得有机胺类化合物的研究进展,包括烯烃的氮杂环丙化反应、苄基C-H键的胺化、醛C-H键的酰胺化、醚的胺化。     

氮杂环丙烷开环反应的研究进展

介绍了碳、氧、硫、氮及含其他杂原子等亲核试剂对氮杂环的开环反应,阐述了烷基、芳基、烯胺、烯醇、烯烃等负碳离子对氮杂环的开环研究.     

芳杂环高分子改性新途径——互相贯穿聚合物网络共混

一、引言 芳杂环高分子一般都具有优良的热稳定性和耐热性能。然而,杂环高分子不易溶解,而且熔点高或不熔融,因此加工困难,成本又贵,限制了它们的用途。后来发展起来的热固性杂环高分子,虽然解决了一部分加工困难问题,成本也降低了很多,但这类树脂在应用上均存在严重脆性的缺点,或者加工条件仍然比较苛刻。芳环高分子因为多半是可溶、可熔的聚合物,在成型加工性能上比杂环高分子好,但成型品的耐势性能往往不能满足人们的要求。 基于芳杂环高分子在国民经济建设,尤其是在国防科研和生产中的特殊地位,芳杂环高聚物的改性工作,成为摆在人们面前的     

噻吩类导电高聚物的研究进展

噻吩类聚合物是研究较为广泛的功能高分子材料。详述了通过化学氧化聚合法和电化学氧化聚合法所合成的噻吩类导电聚合物的性能和用途,常用的结构与性能表征方法以及噻吩类导电聚合物在光、电、磁等各种领域中的应用。     

Synthesis,properties, and practical application of hyperbranched polymers

The methods of synthesis of hyperbranched polymers are considered and systematized with main attention focused on such modern and promising procedures of crosslinking free-radical polymerization as living chain and intense chain transfer regimes. The synthetic approach to hyperbranched polymers via free-radical oxidative polymerization is the first to be put forth. The main problems concerning these polymers are formulated, and the recent advances in this field are generalized and elucidated.     

Radical polymerization of methyl methacrylate in the presence of N,N‐dimethyl‐N‐(methylferrocenyl)amine

The specific features of free‐radical polymerization of methyl methacrylate in the presence of a new initiating system, benzoyl peroxide‐N,N‐dimethyl‐N‐(methylferrocenyl)amine, are studied. Mutual influence of ferrocenyl‐ and amine groups on kinetic parameters of polymerization and on the microstructure of the resulting polymers is found. It is shown that the polymer obtained in the presence of this initiating system has predominantly syndiotactic structure. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 103: 724–727, 2007     

The SPE international award address—1975 polymerization by oxidative coupling—an historical review

The history of PPO®, polymers of 2,6-dimethylphenol, and Noryl® resins is described from the initial discovery through commercialization. The scope of oxidative polymerization as applied principally to phenols and acetylenes is outlined as well as the chemical reactions which can be performed on the resulting polymers.     

Cationic polyelectrolytes,XI. Polymers with quaternary N-atoms in the main chain obtained by condensation polymerization of epichlorohydrin with amines

Water soluble cationic polyelectrolytes containing quaternary nitrogen atoms within the main chain were prepared via condensation polymerization of epichlorohydrin (ECH) with dimethylamine (DMA) and N,N-dialkylaminoalkylamines. The main parameters of the reaction that influence the polymer properties are: DMA/asymmetrical diamine molar ratio, the initial concentration of amine solution, NaOH/amine molar ratio, ECH/amine molar ratio, and asymmetrical diamine structure. The feature of flexible polyelectrolyte own to the investigated polymers was emphasized by the viscosimetric behaviour in dilute aqueous solutions with and without salt presence.     

Rapid ambient temperature atom transfer radical polymerization of tert‐butyl acrylate

BACKGROUND: Atom transfer radical polymerization (ATRP) is considered to be one of the better and easier synthetic tools for the preparation of polymers with controlled molecular weights and polydispersities. Ambient temperature ATRP of tert‐butyl acrylate (tBA) was studied in a detailed manner with ethyl 2‐bromoisobutyrate (EBrB) and tert‐butyl 2‐bromoisobutyrate (tBuBrB) as the initiators for three different degrees of polymerization. RESULTS: Details pertaining to the kinetics of polymerization using different initiators are reported. It is observed that dimethylsulfoxide accelerates the polymerization at room temperature. The use of Cu(II) as the deactivator produces very narrow dispersity polymers. A diblock copolymer, poly(tert‐butyl acrylate)‐block‐poly(methyl methacrylate), was synthesized from the poly(tBA) macroinitiator demonstrating the controlled living nature of the polymerizations. CONCLUSIONS: The rate of polymerization is more rapid with a secondary initiator (ethyl 2‐bromopropionate) compared to the tertiary initiators EBrB and tBuBrB. From the detailed kinetic results it is observed that tris(2‐dimethylaminoethyl)amine was a better ligand compared to tris(2‐aminoethyl)amine in terms of achieving controlled polymerization. Copyright © 2007 Society of Chemical Industry     

Wettability of conducting polymers: From superhydrophilicity to superoleophobicity

The review reports most of the works realized in the field of the surface wettability based on conducting polymers. The surface wettability is highly depending on the intrinsic hydrophobicity of materials and the roughness geometry. Conducting polymers have unique properties allowing to tune the surface wettability, for example, by reversibly incorporating various hydrophobic/hydrophilic doping ions, by changing the nature of the polymerizable core or by functionalization with various hydrophobic/hydrophilic substituents. Conducting polymers are obtained by monomer oxidation using various strategies such as the chemical oxidative polymerization in solution, the electrochemical polymerization on conductive substrates or the vapor-phase polymerization, leading to have an easy control of the surface morphology at micro- or a nanoscale with a surface wettability going from superhydrophilicity to superoleophobicity.     

单组分室温固化乳液涂料的研制

制备了单组分伯胺基/环氧基室温固化乳液涂料:运用局在化技术,将伯胺基团固定于乳胶粒的核层,以乙二醇二甲基丙烯酸酯(EGDMA)为交联剂制备乳胶粒的中间网络层,以甲基丙烯酸缩水甘油酯(GMA)为单体制备乳胶粒的壳层。采用红外光谱、透射电镜、涂膜力学性能等测试手段研究了乳化剂MS-1、UPA用量对乳液聚合稳定性的影响以及熟化温度、UPA、EGDMA用量对涂膜拉伸强度、耐溶剂性的影响。并提出了耐溶剂性涂膜的互穿网络(IPN)结构形成过程的模型。结果表明:不饱和伯胺(UPA)可与苯乙烯、(甲基)丙烯酸酯发生乳液共聚。当MS-1用量不低于总单体质量的3.2%,UPA用量不超过总单体质量的1.5%时,可以得到稳定的乳液。当UPA质量分数为0.8%,EGDMA质量分数为0.2%时,涂膜的拉伸强度最大。涂膜的耐溶剂性对EGD-MA用量更为敏感。     

端胺基聚丁二烯的合成与表征

采用阴离子聚合法合成了端羟基聚丁二烯,通过端基转化法将羟基转化成胺基,从而合成了端胺基聚丁二烯,通过红外光谱（IR）、核磁共振（1H-NMR）、凝胶渗透色谱（GPC）等对其进行了表征。结果表明,所合成的端胺基聚丁二烯相对分子质量分布较窄（≤1.10）,平均官能度接近2,且微观结构可调;通过羟基值与胺基值的测定表明,端基转化率大于98%。     

A soluble ladder copolymer from m-phenylenediamine and ethoxyaniline

A series of partial ladder copolymers were synthesized by chemically oxidative polymerization of m-phenylenediamine (MPD) and o-ethoxyaniline (EOA) using inorganic oxidants in inorganic acidic aqueous media. The polymerization yield, intrinsic viscosity, solubility, and thermal property of the copolymers were systematically studied by changing the comonomer ratio, initial polymerization temperature, polymerization time, oxidant, monomer/oxidant ratio, and acidic medium. As-prepared fine powder of the MPD/EOA copolymers was characterized by IR, UV-vis, and high-resolution ¹H NMR spectroscopies and DSC. Circular dichroism technique was firstly used to characterize chain structure of the copolymers. The results showed that the oxidative polymerization from MPD and EOA is exothermic and the resulting copolymers exhibit a remarkably enhanced solubility in all of the organic and inorganic solvents chosen as compared with totally insoluble MPD homopolymer. The polymers obtained by the oxidative polymerization are real copolymers containing MPD and EOA units but do not contain MPD and EOA homopolymers based on a careful solubility comparison. The actual MPD/EOA molar ratio calculated based on ¹H NMR spectra of the polymers is different from element analysis results. Element analysis indicated that denitrogenation happens during the polymerization linkage among MPD units and the structure consisting of MPD units is different from that reported. The ladder degree of the copolymers might be monitored by controlling MPD/EOA ratio. The DSC measurement indicates that the copolymers do not exhibit melt transition.