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1.
三烷氧基铝与螯合剂反应的产物或用其他方法稳定的二烷氧基铝化合物与含活泼羟基或羧基的双官能基化合物通过缩聚反应可以制得含铝的聚合物。有机铝聚合物的缺点是易水解、分子量不高、在有机溶剂中溶解性较差。本文由乙酰乙酸乙酯基二异丙氧基铝与二乙酰乙酸乙酯基-二(羟乙氧基)乙氧基钛合成有机铝钛缩聚物,并对所得有机铝聚合物的结构及热稳定性进行了表征。  相似文献   

2.
王华丽  白莹  陈实  吴锋  吴川 《化学进展》2013,(8):1392-1400
金属铝是一种很高的能量载体,是开发电池的理想电极材料。由于铝在二次电池中的应用体系主要集中在高温熔盐铝二次电池,其熔盐电解质需要高温,对环境要求苛刻,成本较高难于维护,限制了铝二次电池的发展。近年来,室温离子液体作为二次电池的电解液的研究,使得室温铝二次电池的开发与应用成为可能,人们开始研究基于离子液体电解液的室温有机熔盐二次电池,采用铝或者嵌铝化合物作为电极材料,离子液体作为电解液,与传统的二次电池相比具有很多优点。本文介绍了近年来室温铝二次电池相关的研究和应用新进展,包括金属铝负极的优化和铝枝晶的抑制,可嵌脱铝负极材料的设计,可用于铝二次电池的过渡金属氧化物和导电聚合物正极材料及其性能,以及电解液的要求和离子液体作电解液的优势,并指出了可能存在的问题以及相应的解决办法。  相似文献   

3.
方红云  席振峰 《化学进展》2005,17(6):0-1047
有机铝杂环化合物作为金属杂环化合物中的重要一员,在有机合成中表现出一些独特的性质。有机铝杂环化合物主要包括铝杂环戊二烯、铝杂环戊烯,以及铝杂环戊烷。本文介绍近年来有机铝杂环化合物的合成方法学、反应化学及其在有机合成中的应用研究进展。  相似文献   

4.
ICP-AES法测定钢中酸溶铝和酸不溶铝及全铝   总被引:3,自引:0,他引:3  
应用ICP-AES法测定了钢中酸溶铝和酸不溶铝,并对测定条件及相关参数进行了试验和优化,并于基体的干扰及方法的准确度和精密度也作了研究并标准物质作了验证。用此法所测得结果与标准物质的证书值间无显著差异,将酸不溶铝和酸溶铝的测得值相加即得总铝的量。  相似文献   

5.
含8-羟基喹啉铝配合物的高分子聚合物的合成与表征   总被引:4,自引:0,他引:4  
梅群波  杜乃婴  吕满庚 《化学学报》2004,62(20):2113-2117,F011
通过甲基丙烯酸甲酯(MMA)和含有8-羟基喹啉的单体共聚合成模板聚合物,再与二配体的8-羟基喹啉铝配合物(AlQ2)配位,实现了8-羟基喹啉铝配合物的高分子化,获得了一种高分子量金属配合物发光聚合物,并利用元素分析,FTIR,UV,PL光谱,GPC等方法对其结构和性能作了表征.  相似文献   

6.
氢氧化钠沉淀分离—增感效应—FAAS测定钢铁中铝   总被引:3,自引:0,他引:3  
传统的吸光光度测定钢铁中的铝,往往反应条件苛刻、手续繁杂而难以获得可靠的结果。吉村长藏等报道了有机胺对空气—乙炔火焰法测定铝的增感效应。本文用氢氧化钠作沉淀分离剂,分离钢铁中各种干扰元素,再用空气—乙炔火焰测定钢中铝,并对试验的有关因素进行了探讨。试验证明,该法简便、准确、可靠。适合范围0.05%~1.5%。回收率达99.5%。 1 原理 用硝酸分解试样,再用氢氧化钠作沉淀剂,分离Fe~(2+)、Fe~(3+)、Cr~(3+)、Mn~(2+)、V~(3+)等各干扰元素,铝以AlO_2~-转入溶液,再用盐酸酸化,得Al~(3+)。加入增感剂乙酸铵和三乙醇胺后,在空气—乙炔火焰中测定吸光度。  相似文献   

7.
铝离子电池因其材料成本低、大倍率性能优异和循环寿命超长等优势,而被认为在大规模静态储能应用中具有广阔前景.目前的铝离子电池大部分采用离子液体、尿素和熔融盐等液态电解液,其在实际工程化应用当中存在电解液渗漏的风险.相对而言,全固态电池则可以避免电解液渗漏的问题,还具有因去除隔膜和简化封装所带来的电池整体能量密度提升的优点.但是,目前领域内少有关于全固态铝离子电池的研究.基于此,采用溶液浇筑法,以冠醚作为添加剂和配位基团、以聚乙二醇(PEO)作为基底,制备出无定型结构的聚合物固态铝离子电解质.其中,冠醚不仅作为配位基团与铝离子进行配位提高铝离子的稳定性,而且作为相容性高的添加剂降低聚合物结晶度,从而提高固态电解质的离子电导率.测试表明,制备出的18-6/PEO/Al(CF3SO33体系聚合物固态铝离子电解质是非晶态为主的晶态与非晶态共存的薄膜,且具备很高的离子电导率(室温,5.5×10-6 S/cm;100℃高温,1.86×10-3 S/cm)和较宽的电化学稳定窗口(0~3 V),这为全固态铝离子电池的研发奠定了基础.  相似文献   

8.
铝壶煮沸的饮用水中铝的形态分析   总被引:1,自引:0,他引:1  
用过滤、离子交换和光解氧化分离自来水和经铝壶煮沸的饮用水中铝的形态,以石墨炉原子吸收光谱法测定铝的浓度,采用化学平衡模式计算铝的形态分布。实验结果表明:经铝壶煮沸1min的饮用水中颗凿态铝量比自来水降低了3.3倍,可交换态、不可交换有机态、不可交换无机态铝量分别2增加了1.4、0.5和1.28倍,可交换态和不可交换无机态是铝的主要存在形态。随着煮沸时间的增加,可交换态、不可交换有机态、不可交换无机  相似文献   

9.
研究了铝试剂光度法测定土壤溶液中铝的最佳条件,着重探讨了共存离子,特别是土壤溶液中的无机离子和有机阴离子对测定铝的影响。采用阳离子交换树脂分离,建立了测定土壤溶液及天然水中铝形态方法。用该法可测定总反应性铝、总单核铝和稳定性单核铝。由总反应性铝减去总单核铝求得酸溶性铝。由总单核铝减去稳定单核铝求得不稳定单核铝。与阳离子树脂交换分离-邻苯二酚紫光度法进行了比较。结果表明:邻苯二酚紫光度法灵敏度较高,但铁的干扰较大。铝试剂光度法灵敏度略低,但铁的干扰较少。阳离子树脂交换分离-铝试剂光度法更适合于测定含铁量比较高的土壤溶液中的铝形态。  相似文献   

10.
彭伟  戚佩瑶  董凯旋  贺爱华 《化学学报》2020,78(12):1418-1425
烷基铝(AlR3)作为Ziegler-Natta催化剂体系的助催化剂组分,起到烷基化、还原主金属化合物、参与活性中心形成与演变、链转移剂等重要作用.然而烷基铝自身对二烯烃单体也具有催化作用.本工作采用不同结构烷基铝如三乙基铝(AlEt3)、三异丁基铝(Al(i-Bu)3)、氢化二异丁基铝(AlH(i-Bu)2)、一氯二乙基铝(AlEt2Cl)、二氯一乙基铝(AlEtCl2),研究了烷基铝的种类和浓度对异戊二烯催化行为的影响.采用核磁共振氢谱(1H NMR)、凝胶渗透色谱(GPC)、气相色谱-质谱联用(GC-MS)等对产物的微观结构(顺式-1,4-和反式-1,4-含量)和分子量及分布等进行了表征,探讨了不同结构烷基铝的催化行为.发现烷基铝不仅可以催化异戊二烯齐聚,与微量水作用后还可以引发异戊二烯阳离子聚合,得到顺反混合结构的线性聚合物.烷基铝浓度对其催化行为有较大影响.当n(Al)/n(M)=1050×10-5时,AlEtCl2的催化活性显著提高,产物主要为线性聚合物;而其他结构烷基铝的催化活性较低.当n(Al)/n(M)≤350×10-5,烷基铝自身催化异戊二烯齐聚及聚合能力极弱.过低和过高的烷基铝浓度都不利于获得高分子量聚合物.这为深入理解Ziegler-Natta催化剂体系烷基铝组分的催化作用及其对聚合物的影响提供依据.  相似文献   

11.
The work is devoted to the ionic coordination polymerization of vinyl cyclohexane. During the polymerization of vinyl cyclohexane, side reactions (viz. isomerization into unreactive isomers with internal double bond and transformation of monomer into ethylcyclohexane) occur on complex organometallic catalysts. A procedure has been developed for studying the kinetics of vinyl cyclohexane transformation by analytical gas-liquid chromatography. The effects of various catalytic systems and their individual components on the rates of these reactions have been investigated. From the experimental data, a reaction mechanism has been suggested. It is supposed that ethylcyclohexane is formed by catalytic hydrogenation of monomer with hydrogen evolved during formation of organometallic complex, as well as by the decomposition of the products of the interaction of vinyl cyclohexane with organo-aluminium compounds or titanium derivatives. Most of the isomers with internal double bond (exo- and endocyclic) are formed by a mechanism involving π-bonded intermediates between a monomer and a transition metal and the subsequent σ-alkyl or π-allylic intra- or intermolecular hydrogen transfer.  相似文献   

12.
Copolymerization of vinyl cyclohexane (monomer-1) with styrene was investigated in the presence of the stereospecific complex catalyst TiCl3 + Al(iso-C4H9)3. Monomer reactivity ratios were r1 = 0·177 ± 0·051 and r2 = 2·117 ± 0·370. The monomer unit distributions in the copolymers were estimated by comparison of the i.r.-spectra of copolymers and the isotactic homopolymers using absorption bands at 565 and 1084 cm?1 which correspond to the vibrations of styrene blocks containing ? 5 styrene units and the band at 985 cm?1 characterizing polystyrene crystallinity. The data indicate the tendency towards alternation in the copolymerization. Analysis of the experimental and literature data led to the conclusion that distribution of the units in copolymers of vinyl cyclohexane with α-olefins is determined by the nature of the α-olefin. The following activity series is proposed for α-olefins in their copolymerization with vinyl cyclohexane in the presence of catalytic systems based on titanium salts and organo-aluminium compounds: propylene >; 4-methylpentene-1 >; styrene >; 3-methylbutene-1 ~ vinyl cyclohexane.  相似文献   

13.
Scaffolds play a crucial role in tissue engineering. Biodegradable polymers with great processing flexibility are the predominant scaffolding materials. Synthetic biodegradable polymers with well-defined structure and without immunological concerns associated with naturally derived polymers are widely used in tissue engineering. The synthetic biodegradable polymers that are widely used in tissue engineering, including polyesters, polyanhydrides, polyphosphazenes, polyurethane, and poly (glycerol sebacate) are summarized in this article. New developments in conducting polymers, photoresponsive polymers, amino-acid-based polymers, enzymatically degradable polymers, and peptide-activated polymers are also discussed. In addition to chemical functionalization, the scaffold designs that mimic the nano and micro features of the extracellular matrix (ECM) are presented as well, and composite and nanocomposite scaffolds are also reviewed.  相似文献   

14.
Thermoanalytical studies on specialty polymers in Japan are reviewed. The basic and applied researches for the developments of new specialty polymers such as high-performance polymers, liquid crystalline polymers, and biodegradable polymers during the 1990's are introduced from the standpoint of thermal analysis. Many studies were performed for the improvements of durability and thermal stability of engineering polymers, biodegradable polymers and so on. A special topic of researches on the thermal behavior of polymers by high-pressure differential thermal analysis is included in this review. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   

15.
旋光性高分子在结构上具有一定的空间特异性,因而可以有多种应用。根据铁电材料所必需具备的条件,经过特定的分子结构设计,可以使之具备铁电性能,据此,人们已合成了许多不同类型的铁电聚合物。本文按照铁电聚合物所处的聚集态不同,分别综述了具有铁电特性的晶态和液晶态旋光性聚合物的种类、结构特点及其铁电性能,分析讨论了影响液晶态旋光性聚合物的自发极化率和响应时间的因素。  相似文献   

16.
We study the solvent‐annealing‐induced nanowetting in templates using porous anodic aluminum oxide membranes. The morphology of polystyrene and poly(methyl methacrylate) nanostructures can be controlled, depending on whether the swollen polymers are in the partial or complete wetting regimes, which are characterized by the spreading coefficient. When the swollen polymers are in the partial wetting regime, polymers wet the nanopores by capillary action, resulting in the formation of polymer nanorods. When the swollen polymers are in the complete wetting regime, polymers form wetting layers in the nanopores, resulting in the formation of polymer nanotubes. The solubility parameters of polymers and solvents are also used to predict the wetting behavior of swollen polymers in cylindrical geometry.  相似文献   

17.
荧光聚合物研究进展   总被引:3,自引:0,他引:3  
武照强  孟令芝 《化学进展》2007,19(9):1381-1392
本文总结了近年来荧光聚合物的研究进展,主要介绍了荧光聚合物的分类:按其溶解性能可分为非水溶性、水溶性和两亲荧光聚合物三大类;荧光聚合物的合成:荧光化合物为引发剂、荧光化合物为链转移剂、荧光功能单体聚合、荧光化合物与聚合物的化学键合、非荧光功能单体聚合等五种制备荧光聚合物的设计合成方法;荧光聚合物的应用:荧光聚合物在荧光化学传感器、荧光分子温度计、荧光造影、药物载体、荧光探针等方面的应用研究。  相似文献   

18.
刚性链侧链型液晶高分子合成与研究   总被引:2,自引:0,他引:2  
以自由基聚合方法,合成了一系列含有3个苯环通过酯键相联的液晶性单体及其聚合物,这类刚性液晶基元不通过柔性间隔基而直接竖挂在聚丙烯酸酯大分子主链上,具有很高的Tg·DSC及偏光显微镜结果表明,所有的单体和聚合物均为向列型热致性液晶。  相似文献   

19.
Surface Lewis acid-base properties are significant for polymers materials. The acid constant, K(a) and base constant, K(b) of many polymers were characterized by some researchers with inverse gas chromatography (IGC) in recent years. In this paper, the surface acid-base constants, K(a) and K(b) of 20 kinds of polymers measured by IGC in recent years are summarized and discussed, including seven polymers characterized in this work. After plotting K(b) versus K(a), it is found that the polymers can be encircled by a triangle. They scatter in two regions of the triangle. Four polymers exist in region I. K(b)/K(a) of the polymers in region I are 1.4-2.1. The other polymers exist in region II. Most of the polymers are relative basic materials.  相似文献   

20.
This paper reviews the synthesis and fluid properties of several associating polymer systems. Both hydrocarbon-soluble and water-soluble associating polymers are described. The hydrocarbon-soluble associating polymers are based upon functional poly-octene copolymers. The water-soluble associating polymers are based upon polyacrylamide polymers containing hydrophobic groups.  相似文献   

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