氟代四苯基联苯二胺衍生物的合成与性质

设计合成了两种新型的四苯基联苯二胺衍生物N'N-二苯基-N,N'-双(3-氟苯基)-[1,1'-联苯]-4,4'-二胺(m-FTPB)和N,N'-二苯基-N,N'-双(4-氟苯基)-[1,1'-联苯]-4,4'-二胺(p-FTPB),通过熔点测试、元素分析、FT-IR光谱和1H-NMR谱等手段对其分子结构进行了表征.考察了氟代位置对这类化合物的荧光性质和HOMO能级的影响,结果表明:F原子在四苯基联苯二胺分子苯基的邻、间、对位取代时,荧光发射峰依次发生红移:而F原子在间、对、邻位取代时,HOMO能级依次上升.     

The Physical Properties and Self‐Assembly Potential of the RFFFR Peptide

The self‐assembly of fibers from peptides has attracted a tremendous amount of attention due to its many applications, such as in drug‐delivery systems, in tissue engineering, and in electronic devices. Recently, the self‐assembly potential of the designer peptide RFFFR has been reported. Here it is experimentally verified that the peptide forms fibers that are entangled and form solid spheres without water inside. Upon dilution below the critical fiber concentration, the fibers untangle and become totally separated prior to dissolution. These structures readily bind thioflavin T, resulting in a characteristic change in fluorescent properties consistent with β‐sheet‐rich amyloid structures with aromatic/hydrophobic grooves. The circular dichroism spectroscopy data are dominated by a π→π* transition, thus indicating that the fibers are stabilized by π‐stacking. Contrary to what was expected, the dissolution of the spheres/fibers results in increasing fluorescence anisotropy over time. This is explained in terms of HomoFRET between phenylalanine residues with a T‐shaped π‐stacking mode, which was determined in another study to be the dominant mode through atomistic simulations and semiempirical calculations. Kelvin probe force microscopy measurements indicate that the spheres and fibers have a conductivity comparable to that of gold. Hence, these self‐assembled structures might be applicable in organic solid‐state electronic devices. The dissolution properties of the spheres further suggest that they might be used as drug‐delivery systems.     

碳原子线磁学性质的研究

碳原子线的制备是从马铃薯淀粉为固态碳源以Fe（NO3）3为催化剂前驱体,高温裂解制得。它的磁滞回线呈＂S＂形,一般只有铁磁性物质的磁滞回线才表现出＂S＂,但一般铁磁性物质在常温下的饱和磁矩很大,大约为300 emu/g是碳原子线的300倍,我们把碳原子线的这种磁学性质称之为类铁磁性。通过碳原子线的顺磁共振谱图计算得到每个碳原子有4.78个自由电子,说明碳原子线中有大量的未成对电子。     

表面改性对滑石粉理化性质的影响

采用钛酸酯对滑石粉进行表面改性,以接触角为评价指标,得到最佳的改性工艺参数为:钛酸酯的添加量为3％,反应温度为65℃,反应时间为1.5h.分别采用粒度分析、XRD分析、红外光谱分析以及热重分析对改性前后滑石粉的结构和表面性质进行表征,结果表明,钛酸酯对滑石粉的改性效果显著,表面改性过程不仅发生了物理吸附,还存在化学键合.     

树脂改性对玻璃纤维增强聚合物筋材物理力学性能的影响

在基体树脂中加入阻燃剂和抗静电剂可以改善复合材料的阻燃和抗静电性能,同时也会影响复合材料的力学性能。本文通过在不饱和聚酯树脂中加入阻燃剂和抗静电剂,研究了树脂改性对玻璃纤维增强聚合物（GFRP）筋材拉伸性能、压缩性能、剪切性能、抗静电性能和阻燃性能的影响,分析了改性树脂的阻燃和抗静电机理。试验发现,树脂改性对GFRP筋阻燃和抗静电性能有明显提高,压缩强度有所增加,但GFRP筋拉伸性能和剪切性能有不同程度的降低。     

Modification of the Physical Properties of an Extruded Double-Base Propellant following solvent vapour exposure

Samples of a rolled double-base propellant were exposed to acetone vapour and the rate of solvent uptake observed. The solvent was subsequently removed and dynamic mechanical and extensometer measurements were made on the dried samples. The percentage elongation at break and the ultimate tensile strengths of the samples after solvent treatment were considerably above that of the control samples. The solvent uptake modified the relaxation behaviour of the samples and consequently the values of Young's modulus within the temperature range 30°C to 60°C. The solvent uptake was found to be non-Fickian. Samples that had been thermally annealed prior to solvent vapour treatment were also examined. In general the behaviour was similar to that of unannealed samples but the scale of some of the changes and the rate of solvent uptake was modified.     

紫外引发含氟单体在LDPE薄膜表面的接枝改性

研究紫外光引发甲基丙烯酸十二氟庚酯(DFHMA)在LDPE薄膜表面的接枝改性.考察辐照时间和距离,光敏剂浓度、紫外光强度对接枝率的影响.通过红外光谱分析、扫描电镜及能谱分析对接枝前后的薄膜表面进行表征,结果表明:DFHMA可以通过紫外引发接枝到LDPE等薄膜表面;并对接枝后薄膜的润湿性进行分析,结果表明:接枝含氟单体后薄膜表面能降低、润湿性减弱、接触角变大.     

膨胀珍珠岩/硬泡聚氨酯复合材料改性及物理性能的研究

为了将膨胀珍珠岩和硬泡聚氨酯两种不同的保温材料复合,首先需要对其进行改性,利用硅烷偶联剂KH550对膨胀珍珠岩颗粒进行表面处理,得到活性聚氨酯填充骨料.根据国内外相关规范,测定了成型保温板件的密度、抗压强度、导热系数等物理力学性能.随着膨胀珍珠岩添加量的增加,复合保温材料的密度及抗压强度都有很大的提高.当掺入不同类别的膨胀珍珠岩时,发现粒径较大的膨胀珍珠岩对复合材料抗压性能的提高优于粒径较小的,而在导热系数方面两者却相反.通过上述实验得出了膨胀珍珠岩掺入量以及加入不同种类膨胀珍珠岩对复合材料各性能的影响,通过实验结果确定最终优选方案.将上述两种材料复合,以合理的配比达到共同发挥两种材料各自的优势的目的,此种新型保温材料具有广泛的应用前景.     

Synthesis and Modification of Amine-Terminated Maleic Anhydride-Ethylene Copolymers by Benzaldehyde Derivatives: Characterization and Antimicrobial Properties

Antimicrobial polymers based on poly(ethylene-alt-maleic anhydride) (PEMA) were prepared. Amination of poly(ethylene-alt-maleic anhydride) using diamines of different chain lengths such as ethylenediamine (EDA) and hexamethylenediamine (HMDA) afforded terminal amino groups on the polymers. Antimicrobial polymers were obtained by immobilization of benzaldehyde and its derivatives, which include 4-hydroxybenzaldehyde and 2,4-dihydroxybenzaldehyde onto amine-terminated polymers. The antimicrobial activity of the prepared polymers were examined against different types of microorganisms including Gram-positive and Gram-negative bacteria as well as some fungi. The obtained results revealed that the antimicrobial activity increased with increasing the number of phenolic hydroxyl group and with increasing the spacer length.     

插层改性水滑石及其对聚丙烯力学和阻燃性的影响

通过离子交换法制备了十二烷基磺酸钠、酒石酸氢钠、衣康酸改性的水滑石和十二烷基磺酸钠/衣康酸、十二烷基磺酸钠/酒石酸氢钠协同改性的水滑石（LDHs），通过熔融插层法制备得到了LDHs/PP复合材料。采用红外光谱（FTIR）、X射线衍射（XRD）、热重分析（TGA）对水滑石的结构和性能进行了分析表征，研究了LDHs/PP复合材料的力学性能和阻燃性。结果表明：上述几种单一和复合有机酸及盐改性剂都能不同程度地扩大水滑石的层间距；采用酸/盐协同改性的水滑石不仅有机基团含量较高，而且层间距大，显著提高PP的弯曲强度和阻燃性，表明酸和盐复合改性水滑石有显著协同作用及改性水滑石与PP基体相容性好。     

Self-organization Properties of a GPCR-Binding Peptide with a Fluorinated Tail Studied by Fluorine NMR Spectroscopy

Conjugation of the bioactive apelin-17 peptide with a fluorocarbon chain results in self-organization of the peptide into micelles. Fluorine NMR spectroscopy studies show that the fluoropeptide‘s micelles are monodisperse, while proton NMR indicates that the peptide moiety remains largely disordered despite micellization. A very fast exchange rate is measured between the free and micellar states of the peptide which enables the number of molecules present in the micelle to be estimated as 200, in agreement with values found by dynamic light scattering measurements.     

根据单一气体物理特性计算焦炉煤气低热值

在焦化行业,为充分利用资源、节约能源、减少大气污染,把焦炉煤气输送给下游的煤气用户。那么煤气的热值直接影响到下游加热炉的燃烧状况,热值数据的获得显得尤为重要,但是传统的燃气热值的测定方法存在很多问题,诸如响应时间长,测量范围窄,易冰堵等弊端。为解决这个矛盾,本文将介绍根据单一气体物理特性,通过对煤气组分的分析,依照煤气组分的体积百分含量来计算煤气热值的方法。     

聚合物/无机半导体复合纳米纤维性能研究

利用高压静电纺丝技术结合自组装方法,成功制备了硫化镉/聚环氧乙烷复合纳米纤维,并用X-射线光电子能谱、透射电子显微镜等)研究了复合材料表界面微观结构对纤维形态的影响,从而揭示微观结构和纤维光学性能之间的关系,以便为进一步的器件制备奠定前期基础。     

聚乙烯耐环境应力开裂性能的改进

研究了4种粒状或粉状改性剂(LLDPE、CPE、SBS、EVA)对HDPE的耐环境应力开裂(ESCR)性能的共混改性,探讨了改性机理。结果表明,LLDPE主要通过改变晶体形态和降低结晶度改性,而CPE、SBS、EVA则主要通过加强晶区间连接改性,后者对ESCR的改性效果更显著。     

Surface Functionalization with Phosphazenes: Part 6. Modification of Polyethylene-Co-Polyvinylalcohol Copolymer Surface Plates with Fluorinated Alcohols and Azobenzene Derivatives Using Chlorinated Phosphazenes as Coupling Agents

In this paper we describe a two-step surface modification process of poly(ethylene-co-vinyl alcohol) by exploiting hexachlorocyclophosphazene and poly(dichlorophosphazene) as coupling agents. Part of the P–Cl groups of the chlorophosphazenes is first reacted with the surface hydroxylic groups of the substrate to form covalent P–O–C bonds, the remaining being utilized for successive substitution reactions with different nucleophiles (i.e. 2,2,2-trifluoroethanol, heptadecafluorononanol and 4-hydroxyazobenzene). Modified surface properties, such as hydrophobicity improvement with fluorinated alcohols and photochromic features with the azobenzene derivative, were verified by contact angle measurements and UV–Vis spectroscopy, respectively, while changes in surface composition were demonstrated through XPS spectroscopy.     

聚丙烯物理改性研究进展

介绍了聚丙烯的物理改性及其研究进展,并指出PP填充改性、等离子体改性、助剂改性、共混改性、增强改性是未来发展的方向。     

没食子酸丙酯-富马酸酯衍生物的合成与性能

没食子酸丙酯分别与５种富马酸单酯酰氯反应,制得了５种相应的３,４ 二羟基 ５ （反 β 烷氧羰基丙烯酰氧基）苯甲酸丙酯,这些新化合物同时具有良好的抗氧化和抗菌活性。     

没食子酸丙酯-富马酸酯衍生物的合成与性能

没食子酸丙酯分别与５种富马酸单酯酰氯反应,制得了５种相应的３,４二羟基５（反β烷氧羰基丙烯酰氧基）苯甲酸丙酯,这些新化合物同时具有良好的抗氧化和抗菌活性。