meso-四(4-三甲铵基苯基)卟啉流动注射分光光度法测定痕量镉

本文详细地研究了以meso-四(4-三甲铵基苯基)卟啉为显色剂,正相流路双通道流动注射分光光度法测定镉的实验条件.方法具有快速、灵敏和选择性好等特点.测定镉的相对误差<±3%.     

Interpretation of intrinsic viscosity/temperature data for solutions of poly(phenyl acrylate) and poly(ethylene oxide)

Measured intrinsic viscosities ([η]) at several temperatures (T) within the interval 280–350 K have been found to increase with T for solutions of poly(phenyl acrylate) (PPA) in ethyl lactate. A decrease of [η] with T was observed for aqueous solutions of poly(ethylene oxide) (PEO) at several temperatures within the range 276–358 K. The results have been treated on the basis of eight excluded volume theories, among which the best consistency was afforded by those of Kurata-Stockmayer-Roig, Fixman, and Stockmayer (Padé). These yielded values of ?3.4 × 10^?3 to ?4.7 × 10^?3 deg^?1 and ?0.9 × 10^?3 to ?2.4 × 10^?3 deg^?1 for the temperatur coefficient of the unperturbed dimensions of PPA and PEO, respectively. The derived θ-temperatures were 287 K as the upper critical solution temperature for PPA in ethyl lactate and 365–382 K as the lower critical solution temperature for aqueous PEO.     

阻燃PET的CONE/TGA研究EI

研究了由双 (对 -羧苯基 )苯基氧化膦改性的 PET共聚物的阻燃性质。测定了样品的极限氧指数 (L OI)。采用热重分析仪 (TGA)对试样的热降解行为进行了分析。通过锥型量热仪分析了共聚物及纯 PET样品的燃烧行为 ,显示共聚物具有较好的综合阻燃特性 ,如质量损失速率、热和烟的释放速率等 ,这些性质仅仅通过 L OI和 TGA分析是不能确定的。研究结果表明 ,通过 CONE/     

Synthesis and Polymerization of Bismaleimide Derived from 5(6)-amino-1(4′-aminophenyl)-1,3,3′-trimethyl indane

The acid-catalyzed dimerization of α-methyl styrene led to the formation of trimethyl phenyl indane, which on nitration followed by reduction using hydrazine hydrate gave 5(6)-amino-1(4′-aminophenyl)-1,3,3′-trimethyl indane. This aromatic diamine was used to synthesize bismaleamic acid and imidized to yield bismaleimide. The bismaleamic acid was converted to prepolymer directly by imidizing it in refluxing toluene. All the materials synthesized were characterized using FTIR, ¹H and ¹³C NMR. The direct inlet mass spectral characterizations were carried out for bismaleamic acid, bismaleimide and bismaleimide prepolymer. The fragmentation pattern was discussed in detail and the structure proposed was confirmed. The thermogravimetric studies were done for all the materials and kinetic parameters (energy of activation and frequency factor) were calculated using Dharwadkar and Kharkhanavala method. The structural changes occurring in the thermally polymerized bismaleimide and bismaleimide prepolymer were discussed.     

Synergistic Solvent Extraction and Separation of Lanthanide(III) Ions with 4‐Benzoyl‐3‐Phenyl‐5‐Isoxazolone and the Quaternary Ammonium Salt

The solvent extraction of the lanthanide(III) ions (without Pm) with a 4‐benzoyl‐3‐phenyl‐5‐isoxazolone(HPBI) alone and in the presence of the quaternary ammonium salt Aliquat 336 in perchlorate form (QClO₄) in C₆H₆ was investigated by the slope analysis method. The composition of the extracted species was determined as Ln(PBI)₃ and Q[Ln(PBI)₄] (Q⁺ is the quaternary ammonium salt cation). The values of the equilibrium constant were calculated. Synergistic effects were found for all lanthanide metals when they were extracted with a binary mixture of HPBI and QClO₄. The influence of the synergistic agent on the extraction process has been discussed. The parameters of the extraction process were determined. The separation factors between adjacent metals were evaluated.     

Hollow polymeric nanostructures—Synthesis, morphology and function

The development of reliable synthetic routes to polymeric nanostructures of well-defined composition, morphology and function is of scientific importance and technological interest. The generation of functional hollow polymeric nanostructures, hollow nanospheres and nanotubes in particular, can be achieved through direct and template-directed synthesis, core-shell precursors, and self-assembly of copolymers and polymer conjugates, as well as from dendrimers. The ability to prepare precursor macromolecules of well-defined structure and architecture has been substantially enhanced by recent advances in controlled radical polymerizations. The application and potential application of the hollow polymeric nanospheres and nanotubes as nanoreactors, and in diagnostics, encapsulation, controlled release, and other stimuli-responsive systems are also described.     

绿色试剂碳酸苯甲酯的合成及其应用研究

绿色试剂碳酸苯甲酯是一种反应活性较高的碳酸酯,可作为羰基化、甲基化和甲氧羰基化试剂.利用碳酸二甲酯和碳酸二苯酯合成了碳酸苯甲酯;考察了反应温度、投料比、不同催化剂对碳酸苯甲酯合成收率的影响.得到最佳反应条件:二丁基氧化锡(Bu2SnO)催化下,投料比1:1,154℃反应9 h生成碳酸苯甲酯(MPC),产率52.3%,并...     

Pd-Fe/TiO2催化硝基苯和醇羰基化合成苯氨基甲酸酯

以Pd-Fe/TiO2为催化剂,硝基苯与醇或酚进行羰基化反应合成苯氨基甲酸酯,考察了反应条件和不同反应底物对羰基化反应的影响.结果发现Pd-Fe/TiO2催化剂对羰基化反应具有较好的催化活性,在硝基苯20mmol,醇或酚21mmol,Pd和Fe负载量分别为0.3％和0.1％,催化剂用量96mg,乙腈20mL,CO压力0...     

酰乙基苯基次膦酰肼铝盐的合成与应用

以羧乙基苯基次膦酸、水合肼为原料,二甲苯为溶剂,合成膨胀型阻燃剂酰乙基苯基次膦酰肼铝盐,其最适宜的工艺条件为羧乙基苯基次膦酸与水合肼的摩尔比为1∶1,在140℃下回流反应6h,再加入硫酸铝成盐,产品得率为93.1％,用红外、核磁、元素分析、DSC等对产品的结构与性能进行了表征,并对其在聚对苯二甲酸丁二醇酯(PBT)中的...