PTFE/纳米SiO2复合材料的制备及其力学性能

聚合物／纳米级无机粒子复合材料是纳米材料中的一种具有重要价值的新型材料，可广泛应用于橡胶、塑料、纤维三大合成材料之中。采用纳米级无机粒子填充聚合物基复合材料，可以在材料的补强、增韧等改性中获得良好的效果。本文以纳米SiO2为填料，将其经过有机处理后，制备了FIFE／纳米SiO2复合材料，并研究了纳米SiO2的含量对PTFE复合材料性能的影响。     

聚酰胺/粘土纳米复合材料

聚酰胺／粘土纳米复合材料是一种新型的有机－无机纳米复合材料。在无机物含量远少于常规填充复合材料的情况下就可以具有较好的力学性能、阻隔性能等,热稳定性能也显著提高,并具有阻燃性和各向异性。是一种性能优异的、具有广泛应用前途的纳米复合材料。综述了该纳米复合材料的制备、性能和应用前景等。     

PbS纳米粒子与全共轭高分子的自组装膜原位复合及其光电转换性质

无机纳米粒子因其在催化、磁学、光子学等方面的特殊性质而越来越受到关注,纳米粒子粒径及分布可以人为控制,由此能够改变与有机聚合物所形成的纳米复合材料性能,在各种无机纳米粒子／有机聚合物复合材料制备方法中,纳米反应器(Nanoreactor)技术正日益受到关注,与常规的作为化学反应特定场所的化学反应器不同,纳米反应器不是一般的具体的机械设备,     

聚酰亚胺/蒙脱土纳米复合材料

利用插层法合成的聚酰亚胺／蒙脱土纳米复合材料相比于纯聚酰亚胺有更好的力学性能、热稳定性、气体阻隔性及更低的介电性、吸湿性和热膨胀性。是一种性能优异、具有广泛应用前途的新型有机、无机－纳米复合材料。这是因为粘土在聚酰亚胺基体中以纳米尺度均匀分散并与基体形成了强的化学结合。本文重点综述了该复合材料的制备、结构表征及性能等方面的研究，并展望该材料的应用前景。     

聚合物纳米材料研究进展——Ⅱ.聚合物/无机纳米复合材料

复合物纳米材料包括纳米聚合物和聚合物／无机纳米复合材料。本文综述了聚合物／无机纳米复合材料的研究进展，重点介绍了溶胶－凝胶法，原位生成法，模板法，插层复合，沉积法，机械粉碎，分子平壤 ，溶液或融混合法的研究进展。     

聚苯胺/膨润土纳米复合材料的合成与表征

通过嵌入手段设计与合成同时具有某些无机和有机物双重性能的新型材料－无机／有机纳米复合材料,是科学家们关注的课题[1].Inoue等人[2]采用蒙脱土吸附苯胺单体然后电氧化的方法制备了聚苯胺／蒙脱土（Pan／Mont）复合材料,由于Mont片体的表面吸附了苯胺,所合成的为聚合物包覆的复合材料,这样在一定的程度上影响了材料的各向异性．本文采用离子交换,洗涤除去吸附在粘土颗粒表面的单体,成功地合成了非包覆的聚苯胺／膨润土壤（Ben）层状纳米复合材料,并用FTIR等方法对材料进行了表征．该材料兼有粘土的离子交换性能和聚苯胺的良好…     

有机 无机纳米复合光电材料研究进展

很久以来人们就尝试着结合有机材料和无机材料的性质于一种复合材料。在还没有复合材料这一概念时,有机/无机复合结构已被广泛用于聚合物工业中——无机添加剂(矿物、粘土、滑石等)被加入聚合物中以改善其性能。过去十年中,关于有机/无机纳米复合材料的研究工作已成为材料学科的一个重要领域。不同于传统的复合材料,有机无机纳米复合材料其相微区通常为纳米尺度,有时甚至减小到分子水平的复合。复合材料的性质不但与各组分的性质有关,而且各组分相的形态和其间界面性质密切相关,后两者对决定材料的整体性质起着至关重要的作用^[1,2].     

原位沉析法制备有序排列四氧化三铁/壳聚糖纳米复合材料的研究

生物矿物由于具有完美结构及独特的生物活性,使其成为制备新型有彬无机杂化纳米复合材料的思想来源,在目前制备的有机／无机纳米复合材料中,纳米粒子在聚合物基质中大部分是无规分散的,但无机纳米颗粒在有机物中的有序排列是生命体中的一种根本体现,有序排列会使材料的性能更加优异。人骨的主要成分是纳米羟基磷灰石晶体和胶原,羟基磷灰石晶体是沿着胶原纤维的长轴方向有序排列的,这使得人骨不仅具有生物活性,而且具有非常好的力学性能。     

细乳液聚合法制备有机/无机纳米复合材料

无机纳米粒子的引入可以使聚合物材料获得抗菌、导电和防紫外等诸多特性,但无机纳米粒子在聚合物基质中易团聚、引入量少,难以充分发挥其优点。细乳液聚合法基于其独特的成核方式--液滴成核,能够提高无机纳米粒子在聚合物基中的分散性和引入量,且复合材料的形貌易于控制,是目前制备特殊形貌有机/无机纳米复合材料的一种有效手段。本文介绍了有机/无机复合纳米材料的细乳液制备过程,综述了近年来不同无机纳米粒子与有机基质复合的研究进展,例如：纳米SiO₂、纳米ZnO、金属纳米粒子、纳米氧化石墨烯等。最后就其发展现状提出了几点建议。     

高抗冲聚苯乙烯/粘土纳米复合材料的制备、热稳定性及流变性能

用双螺杆挤出共混法制备了高抗冲聚苯乙烯 (HIPS) 有机蒙脱土 (Org MMT)插层纳米复合材料以及HIPS 无机蒙脱土 (MMT)常规复合材料 .分别用TGA和毛细管流变仪研究了它们的热性能与流变性能 ,并比较了两种结构材料的性能差异 .结果表明 ,纳米复合材料比纯HIPS和常规的复合材料具有更好的热稳定性和流动性 ,前者具有更强的剪切变稀行为 .此外 ,当蒙脱土达到纳米级分散时 ,复合材料的表面也变得更加平整光滑 .     

How will additives shape the future of plastics?

Additives are essential components of plastic formulations providing maintenance and/or modification of polymer properties, performance and long-term use. The extension of polymer properties by additives has played a substantial role in the growth of plastics. At the beginning of the plastics age additives were used mainly to maintain polymer properties and to help plastics to survive heat treatment during transforming processes. The next generation of additives provided extension of service life as well as modification of mechanical and physical properties. These well-established additives - antioxidants, heat stabilizers, light stabilizers and others - cover the requirements of standard plastics and today's mass applications. The more recent developments of high-performance additives address more stringent or new requirements, more severe processing and use conditions and/or environmental concerns, but still with the main target of maintaining plastic properties. The future will introduce more and more new effects and functionalities through additives in plastic applications tailoring the properties of polymers and offering a vast potential of innovation in the plastics area. Recent examples of emerging technologies show that additives will not only modify the polymer itself and add new properties, but can also, when incorporated into the plastic, beneficially impact properties, which are of high value for the user. The paper shows the role of additives used in plastics from the past to the present with the focus on stabilization and performance of additives incorporated during melt processing, and outlines future trends.     

聚磷腈高分子

简要综述了聚磷腈高分子的合成、结构与物理性能及在新型功能材料方面的应用,包括高分子电解质、光导电材料、非线性光学材料以及生物医用材料。     

Trends in Conjugated Chalcogenophenes: A Theoretical Study

Heavy atom substitution in chalcogenophenes is a versatile strategy for tailoring and ultimately improving conjugated polymer properties. While thiophene monomers are commonly implemented in polymer designs, relatively little is known regarding the molecular properties of the heavier chalcogenophenes. Herein, we use density functional theory (DFT) calculations to examine how group 16 heteroatoms, including the radioactive polonium, affect polychalcogenophene properties including bond length, chain twisting, aromaticity, and optical properties. Heavier chalcogenophenes are more quinoidal in character and consequently have reduced band gaps and larger degrees of planarity. We consider both the neutral and radical cationic species. Upon p-type doping, bond length rearrangement is indicative of a more delocalized electronic structure, which combined with optical calculations is consistent with the polaron-model of charge storage on conjugated polymer chains. A better understanding of the properties of these materials at their molecular levels will inevitably be useful in material design as the polymer community continues to explore more main group containing polymers to tackle issues in electronic devices.     

IMPACT PROPERTIES OF METALLOCENE - CATALYZED ETHYLENE-α-OLEFIN COPOLYMERS

The impact properties of two selected metallocene-catalyzed ethylene-butene copolymers and one conventionalcopolymer were evaluated using Izod impact test. It is found that the metallocene-catalyzed copolymer shows superior impactproperties. This result was explained on the basis of the more homogeneous inter-molecular composition distribution andnarrower molecular weight distribution, which leads to more homogeneous morphology with fewer defects. Stepwisecrystallization improves the impact properties, especially in the crack propagation process, to a large extent. This is due to thedecrease of entanglements by stepwise crystallization, which is advantageous for the chain slip and shear. The polymer withheterogeneous intra-molecular composition distribution exhibits a more evident improvement of impact properties understepwise crystallization.     

N-取代基马来酰亚胺均聚合研究进展

N-取代基马来酰亚胺聚合物具有良好的热性能,近些年来随着材料性能的要求提高,对这类单体的研究也越来越多,本论文综述了N-取代基马来酰亚胺在自由基、阴离子聚合、配位聚合等方面的均聚合研究进展。     

Simple rules for the understanding of Heusler compounds

Heusler compounds are a remarkable class of intermetallic materials with 1:1:1 (often called Half-Heusler) or 2:1:1 composition comprising more than 1500 members. Today, more than a century after their discovery by Fritz Heusler, they are still a field of active research. New properties and potential fields of applications emerge constantly; the prediction of topological insulators is the most recent example. Surprisingly, the properties of many Heusler compounds can easily be predicted by the valence electron count. Their extremely flexible electronic structure offers a toolbox which allows the realization of demanded but apparently contradictory functionalities within one ternary compound. Devices based on multifunctional properties, i.e. the combination of two or more functions such as superconductivity and topological edge states will revolutionize technological applications. The subgroup of more than 250 semiconductors is of high relevance for the development of novel materials for energy technologies. Their band gaps can readily be tuned from zero to ≈4 eV by changing the chemical composition. Thus, great interest has been attracted in the fields of thermoelectrics and solar cell research. The wide range of their multifunctional properties is also reflected in extraordinary magneto-optical, magnetoelectronic, and magnetocaloric properties. The most prominent example is the combination of magnetism and exceptional transport properties in spintronic devices. To take advantage of the extremely high potential of Heusler compounds simple rules for the understanding of the structure, the electronic structure and the relation to the properties are reviewed.     

Sugar surfactants — aggregation,interfacial, and adsorption phenomena

The latest research work provides us with basic knowledge about some selected properties of systems containing sugar surfactants. Now we are able to understand the behavior of aqueous solutions reasonably well and very recently progress was made with respect to the properties of microemulsions. However, little is still known about the adsorption properties. Apart from the need for more fundamental research, the future task will be to handle more complex systems. Here complex refers to multi-component mixtures used in technical applications, but also to biotechnological applications where the structure of the surfactant is more complex. Promising future developments in this field are outlined.     

The unusual physicochemical properties of azulene and azulene-based compounds

This review shows the unusual physicochemical properties and wide application of azulene and its derivatives. The recent synthesis strategies of kinds of substituted azulene are also listed.     

Coating Paper with the Fluorescence Assistant of Ternary Complexes of CMC/Eu/TTA

Carboxymethyl cellulose (CMC), one of the derivatives of cellulose, are mainly used as thickeners, dispersants, adhesives, extenders and films because of their water solubility and gel-forming properties. Especially, because it presents more and more excellent properties on the making paper technology, the great of paper engineers attach importance to it.     

Molecular fragment shape variation index for functional groups and the holographic properties of electron density

For a specific functional group, considered as a molecular fragment, the rest of the molecule produces a range of interactions which influence various properties of the functional group. Considering a family of molecules with the “same” functional group, the range of variations in properties determines the range of chemical reactivity of the functional group, and a similar conclusion is valid for more general molecular fragments. By the application of conventional as well as more advanced indices of fragment properties, including local electron density shape characterization, various shape variation indices can be introduced for fragments, and their relations to the holographic properties of electron densities can be examined.