不同V型辅助配体构筑的两个镉配位聚合物的合成、结构和荧光性质

在溶剂热条件下,合成了2个基于V型辅助配体（bipmo、bppmo）的镉配位聚合物{[Cd （bipmo）（NDC）]·1.75H₂O}_n（1）和{[Cd （bppmo）（NDC）（H₂O）]·H₂O}_n（2）,其中H₂NDC=2,6-萘二羧酸,bipmo=双（4-（1H-咪唑-1-基）苯基）甲酮,bppmo=双（4-（吡啶-4-基）苯基）甲酮。利用单晶X射线衍射、键价和分析、红外光谱和元素分析对其结构进行了表征。研究发现,配合物1具有二重互穿的{6³}拓扑结构。配合物2同样是3-连接的{6³}拓扑,却存在三重穿插结构。分析表明,V型配体对最终结构的形成有很大影响。此外,对配合物1和2的发光性质也进行了详细研究。     

不同V型辅助配体构筑的两个镉配位聚合物的合成、结构和荧光性质

在溶剂热条件下,合成了 2 个基于 V 型辅助配体(bipmo、bppmo)的镉配位聚合物{[Cd(bipmo)(NDC)]·1.75H₂O}_n (1)和{[Cd(bppmo)(NDC)(H₂O)]·H₂O}_n (2),其中 H2NDC=2,6 萘二羧酸,bipmo=双(4 (1H 咪唑 1 基)苯基)甲酮,bppmo=双(4 (吡啶 4 基)苯基)甲酮。利用单晶X射线衍射、键价和分析、红外光谱和元素分析对其结构进行了表征。研究发现,配合物1具有二重互穿的{63}拓扑结构。配合物2同样是 3 连接的{6³}拓扑,却存在三重穿插结构。分析表明,V型配体对最终结构的形成有很大影响。此外,对配合物1和2的发光性质也进行了详细研究。     

交联壳聚糖／聚醚半互穿聚合物网络水凝胶中水的状态

合成了一种由戊二醛交联的壳聚糖与聚醚形成的半互穿聚合物网络的水凝胶，用ＤＳＣ法并结合ＩＲ光谱研究了该水凝胶中水的状态及水与聚合网络间的相互作用。     

低浓度HPAM/AlCit交联聚合物溶液性质研究

采用粘度法、扫描电镜（SEM）、核孔膜过滤、动态光散射（DLS）和27Al NMR法，研究了高分子量低浓度的部分水解聚丙烯酰胺（HPAM）与柠檬酸铝（AlCit）体系交联反应过程溶液性质变化.结果表明，HPAM与AlCit反应在低剪切速率时体系粘度随反应进行而降低，在剪切速率较高时具有剪切稠化现象，HPAM与AlCit反应过程中交联态Al的自旋 晶格弛豫时间随反应进行变短.低浓度的HPAM与AlCit发生分子内交联反应形成交联聚合物线团（LPC）在水中的分散体系，即交联聚合物溶液（LPS）.交联聚合物溶液中LPC的平均流体力学半径约为238 nm，其形态接近球形，具有多分散性. LPS对1.2 μm核孔膜的封堵程度与其反应时间有关.     

水/醇溶聚合物界面材料在聚合物光电器件中的应用及性能研究

系统研究了系列不同共轭与非共轭水/醇溶聚合物作为界面修饰材料在聚合物发光二极管和聚合物太阳电池中的应用及结构性能关系. 研究了界面层厚度, 器件金属电极功函对材料界面修饰性能的影响. 在此基础上, 系统对比研究了共轭与非共轭水/醇溶聚合物界面材料在不同聚合物光电器件中界面修饰性能的差别. 内建电势测试与器件研究结果表明, 在聚合物发光二极管中, 共轭材料表现出明显优于非共轭材料的性能, 特别是在超高功函数的金属金电极器件中, 共轭的水/醇溶聚合物材料依然表现出很好的电子注入/传输性能; 在聚合物太阳电池中, 共轭材料的界面修饰性能也优于非共轭类界面修饰材料.     

β-环糊精/环氧氯丙烷水凝胶中水的存在状态及其溶胀特性

研究了β-环糊精／环氧氯丙烷水凝胶的合成工艺条件,发现该水凝胶透明性好,其干胶具有溶胀速度快的且在－40－200℃范围内不存在玻璃化转变,用DSC对β-环糊精／环氧氯丙烷水凝胶的溶胀过程及水在聚合物网络中的存在状态进行了研究,结果表明,该聚合物在溶胀过程中水首先分布于β-环糊精的外围亲水空间依次形成非冻结结结合水,可阈结结合水及游离水、其后水分布于β-环糊精内腔空间,当达到溶胀平均后,β-环糊精的内外空间都分布有水。     

醇/水混合溶剂中碱性聚合物电解质独特的溶解行为

Self-aggregated quaternary ammonium polysulfone (aQAPS) is a high-performance alkaline polymer electrolyte that has been applied in alkaline polymer electrolyte fuel cells (APEFCs). For a long time, N, N-dimethyl formamide (DMF) has been considered the best solvent to dissolve aQAPS, but the high boiling point of DMF makes it hard to remove from the electrodes, which potentially poisons the electrocatalysts. Our recent experiments have shown that although aQAPS is unable to dissolve in ethanol, n-propanol, or water, it can dissolve in the mixture of these alcohols and water. This peculiar dissolution behavior significantly facilitates the fabrication of the membrane electrode assembly (MEA) for APEFCs, even though it has not been understood. In this work, atomistic molecular dynamics (MD) simulations were employed to study the dissolution behavior of aQAPS in different solvents, including water, methanol, ethanol, n-propanol, DMF, and the mixture of these non-aqueous solvents and water. The conformation of the aQAPS chain in pure solvents agreed well with the dissolution behavior observed in the experiments, even though in the water-containing mixed solvents, the aQAPS chain tended to be in a more contracted state. The simulations further revealed that the water component in the mixed solvents played dual roles. On one hand, the hydrocarbon chain of aQAPS was compressed to a contracted state upon the addition of water, because of the hydrophobic effect. On the other hand, water can drive the dissociation of the counterion (Cl^{–­ ­ ­} ), which led to an enhancement in the solute-solvent interaction energy and thus facilitated the dissolution of aQAPS. In most mixed solvents, the compensation of these two interactions resulted in a general increase in the total solute-solvent interaction energy; therefore, the addition of water was energetically favorable for the dissolution of aQAPS. This study not only furthers our fundamental understanding of the dissolution behavior of polyelectrolytes but also is technologically significant for the development of better APEFCs.     

热力学体系状态性质的加和性及应用

热力学体系状态性质的加和性及应用何玉萼（四川大学化学系成都６１００６４关键词热力学状态函数加和性中图分类号Ｏ６４２热力学中我们用实验可测量如压力ｐ、体积Ｖ、温度Ｔ等及在热力学经验定律基础上，经数学演绎定义的导出热力学量如焓Ｈ、熵Ｓ和Ｇｉｂｂｓ函数Ｇ等...     

金属纳米粒子/聚合物体系的稳定性及其机理

金属纳米粒子由于其小的尺寸和大的比表面积等特点,使其具有独特的热性能、电性能、磁性能和光性能,以及很强的团聚趋势。因此金属纳米粒子是否被稳定在纳米尺度内,是它们能否表现出独特性能的关键。本文综述了非离子聚合物、聚电解质、两亲聚合物、双亲水聚合物、树状聚合物对金属纳米粒子的稳定作用及其稳定机理的研究进展。     

金属纳米粒子/聚合物体系的稳定性及其机理

金属纳米粒子由于其小的尺寸和大的比表面积等特点,使其具有独特的热性能、电性能、磁性能和光性能,以及很强的团聚趋势.因此金属纳米粒子是否被稳定在纳米尺度内,是它们能否表现出独特性能的关键.本文综述了非离子聚合物、聚电解质、两亲聚合物、双亲水聚合物、树状聚合物对金属纳米粒子的稳定作用及其稳定机理的研究进展.     

Drug Release and In Vitro Assays of Bioactive Polymer/Glass Mixtures

The bioactive behaviour and drug release of samples composed by sol gel glass with composition 80SiO₂-16CaO₂-4P₂O₅% mol, polymethylmethacrylate (PMMA) and gentamicine or ibuprofen have been studied. The bioactive behaviour of the samples does not depend on the amount (5% and 10% in weight) or on the type of drug used in this study. In all the cases the SEM micrographs show the formation of a layer that covers the surface of the samples after 24 hours soaked in simulated body fluid (SBF). X ray diffraction patterns show two broad peaks after being soaked 3 days. These peaks could be identified with an apatite-like phase, characteristic in this kind of studies.On the contrary, the release kinetics is strongly dependent on the drug employed. In the case of gentamicine, the curve shows a high slope during the first day soaked in SBF and the complete release occurs before 150 hours. For the ibuprofen samples, the drug release is much slower; the samples containing 10% of ibuprofen do not reach the total release after 600 hours. This different behaviour could be related with the solubility of both drugs in aqueous media.     

阴、阳离子表面活性剂混合体系在硅胶/水及硅胶/矿化水界面上的吸附

研究阴、阳离子表面活性剂混合体系(十二烷基氯代吡啶,辛基磺酸钠,辛基三乙基溴化铵/十二烷基苯磺酸钠)在硅胶,纯水和硅胶,矿化水界面上的吸附作用,探讨阴(阳)离子表面活性剂的存在对阳(阴)离子表面活性剂吸附作用的影响．结果表明,阴离子表面活性剂的存在基本不影响阳离子表面活性剂在带负电固体表面的吸附;而阳离子表面活性剂的存在却使本来吸附量就不大的阴离子表面活性剂在带负电的固体表面上不再吸附．在矿化水中阳离子表面活性剂的吸附量比在纯水中明显降低．从硅胶表面吸附机制解释了所得结果．     

Polydispersity Effect on the Adsorption of Polymer Mixtures

The changes in molecular mass distribution (MMD) after adsorption from solution in concentration regions below and above the critical concentration of overlapping have been studied for various polymers and their mixtures. It was found that the formation of entanglements in both binary and ternary solutions affects the changes in MMD. For binary and ternary solutions above the critical concentration of overlapping, C*, the entanglements lead to diminishing selectivity of adsorption of high-molecular-weight fractions. Simultaneously, transition through C* diminishes adsorption of the fractions of higher surface activity. It may be assumed that the entanglements play the role of an additional energetic barrier which macromolecules must overcome to be adsorbed. The transition through the critical concentration of overlapping for the case of binary solutions diminishes the selectivity of adsorption of high molecular fractions. Adsorption of polar polymers from the ternary solutions both below and above C* leads to the appearance of the bimodality of MMD due to adsorption of surface-active fractions. Copyright 2000 Academic Press.     

药用高分子材料亲水性修饰的研究进展

高分子材料在药物制剂和制药工艺上具有广泛的应用价值。新型制剂的研发与药用高分子材料的性能密切相关,特别是高分子胶束等两亲性高分子材料的使用尤为广泛,也是高分子材料当今研究的热点。本文着重对常见药用高分子材料亲水性修饰的亲水片段进行了概括总结。根据亲水片段的大小,分为小分子修饰、水溶性聚合物修饰以及水溶性高分子修饰三个部分,对药用高分子材料亲水修饰的修饰剂和修饰产物的性质特点、修饰方法以及其中的优势和不足尽可能的进行了综述,并对此进行了讨论和展望,以期能够给同行们提供参考并共讨论。     

Interfacial Properties of Asymmetric Polymer Mixtures

Using a Monte‐Carlo simulation of a continuous space Rod Bead Model the interface properties of systems of flexible polymer chains with different sizes of monomers are investigated. An immiscible polymer blend in the strong segregation state is modeled by a double sandwich system of chains differing by an factor of two in the size of the beads and the interfacial tension is calculated by a virial theorem method. The simulation data are compared to self‐consistent mean field and experimental data. The results show that the simulation data agree very satisfactory with mean‐field results. The interfacial tension decreases for asymmetric systems in comparison to symmetric systems with comparable volume contents of monomers and interaction strengths due to a decrease of the effective interaction. The parameters of the investigated systems are close to the properties of PS, PMMA and PI melts. A comparison with experimental results yields a very good agreement with data for PS/PMMA and less satisfactory for PS/PI. Additionally to the interfacial tension we have studied the interfacial width, the deformation of polymer chains near the interface, distributions of chain ends, monomer densities and distributions of centers of mass of chains.

Snapshot of a typical configuration for chains with different monomer sizes and equal number of monomers per chain.     

Nmr Spectroscopic Determination of Water In Deuterium Oxide/Water Mixtures

Abstract

Deuterium oxide was determined in synthetic mixtures of 70–100 % D₂O and 90–100 % D₂O by NMR spectroscopy with a Varian A-60 NMR spectrometer using peak heights and areas. The standard deviation for the best results was 0.4 % D₂O.     

Separation into Phases of Polymer Mixtures in Solution

When three different polymers are dissolved in a common solvent and the total polymer concentration is above a certain value, three liquid layers are obtained because of the limited compatibility of the polymer components with one another. Tests have been carried out at room temperature on solutions of polystyrene t polyvinyl acetate + polyvinyl chloride in tetrahydrofuran, and polystyrene t polyvinyl acetate t atactic polypropylene in benzene. Analysis of the individual layers yielded the following results: each polymer is always contained in each layer; the mixing ratios of the polymers in the three layers are generally different from one another and differ also from the mixing ratio of the starting mixture; each of the three layers is distinguished from the others by the fact that a specific polymer has been accumulated therein in preference to the other polymers. Concerning the quantitative distribution of the polymers among the layers, some laws could be found which can be explained qualitatively on the grounds of molecular-physical considerations. A solution of polystyrene t polyvinyl acetate t polyvinyl chloride t atactic polypropylene in tetrahydrofuran (equal amounts of polymers, total concentration about 10 g/100 ml) forms four layers, the composition of which was also determined by analysis.

When solutions of polymer mixtures are evaporated, separation into phases takes place because the polumers become incompatible with one another when the concentration exceeds a certain value. As a result, strongly inhomogeneous films are obtained after evaporation of the solvent. If the inhomogeneity of the films is not taken into consideration, misleading results may be obtained in the analysis of the films.

It is shown that in the system polystyrene + polyvinyl acetate, with tetrahydrofuran as solvent, surprising phenomena appear on the addition in stages of cyclohexane. The phenomena are due to the overlapping of separating and dissolving processes which have, in part, opposite actions.     

Effect of Hydrophilic Polymer on Solubilization of Fenofibrate by Cyclodextrin Complexation

The present work investigates the possibility of improvement of the complexation efficiency of cyclodextrin towards a drug by adding a third auxiliary component (hydrophilic polymer). Phase solubility Analysis at 25 °C was used to investigate the interaction of the drug in both the binary systems (viz. Drug-Cyclodextrin and Drug-Polymer) and the ternary system (Drug-Cyclodextrin-Polymer). The combined use of polymer and cyclodextrin was clearly more effective in enhancing the aqueous solubility of the fenofibrate in comparison with the corresponding drug-cyclodextrin or drug-polymer binary systems. Hydrophilic polymers increased the complexation efficacy of cyclodextrin towards fenofibrate (as shown by the increased stability constants of the complexes). Polyvinyl Pyrollidone (PVP) was found to be most effective in enhancing the solubilization of fenofibrate by β-Cyclodextrin, the best results were obtained in ternary system with β-Cyclodextrin in presence of 1%w/v (PVP). Formulated ternary system with optimized drug:cyclodextrin:polymer ratio of 1:3.5:1 w/w resulted in a significant improvement in the dissolution rate of fenofibrate and showed 90% dissolution efficiency (D.E) as compared to around 15% and 83% of the plain drug and binary system respectively. DSC studies was carried out to characterize the ternary complex.     

Measurement and Prediction on the Surface Properties of Dimethyl Sulfoxide/Water Mixtures

Pendent drop method was adopted to measure the surface tension of dimethyl sulfoxide(DMSO)/water mixtures. A new pendent drop apparatus was built up and checked with water, and a good agreement of our data with literature could be found. With the new apparatus, the surface tensions of nine DMSO/water mixtures with mass fractions of water from 0.1 to 0.9 were investigated in a temperature range of 298-338 K. The expanded uncertainty for surface tension measurement was estimated to be 0.5% at a confidence level of 95%(k=2) in the whole temperature range. A thermodynamic-based relation was used to predict the surface properties of DMSO/water mixtures. Based on the relation and Gibbs adsorption theory, a prediction model was proposed for the calculation of surface relative excess and the thickness of the surface molecule layer.