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1.
1 Introduction Silicon-containing polymers have been intensively studied in the past half-century, and a great number of papers, patents and books have been published on the synthesis, properties and applications. Silicon-containing polymers, especially polymers containing silicon atoms in the backbone, including some major species as polysiloxane, polysilane, polysilazane, etc. have chains constructed of alternately arranged silicon and oxygen atoms with organic groups attached to the silicon…  相似文献   

2.
1 Introduction Nanometer scale devices, as the next generation devices of electronics, have got a worldwide attention and rapid development recently. Simultaneously, conjugated polymers have been applied in organic electronics successfully because of their outstanding electronic-photonic properties. However, as far as we know few reports have dealt with the fabrication of nanometer scale devices by using conjugated polymers, although the combination of nanometer scale devices and polymers will…  相似文献   

3.
1 Introduction General synthetic polymers such as polyethylene, polyvinyl chloride, polystyrene etc. have been produced and used in large quantities. They are very cheap, but their wastes are difficult to decompose in nature so to cause environmental pollution .In order to overcome such disadvantage, various kinds of biodegradable synthetic polymers such as polyactic acid, aliphatic polyester, polyvinyl alcohol complexes etc. have been researched~([1]). However, they are expensive, so cannot b…  相似文献   

4.
Micro-and nano-patterning of polymers is essential in nanoscience and nanotechnology. Single macromolecule is a particle with nano-scale dimension; polymers have multi-structure, various configurations, and ability of forming blends with varying polymers or copolymers with different monomers, which will result in plenty of patterns of micro- and nano-scale. Besides, special physical and mechanical properties of polymers will not only be used to make patterns in many existing microfabrication technologies, but also develop new patterning techniques. The topic of micro-and nano-patterning of polymers has been granted as a key project by the National Natural Science Foundation of China.  相似文献   

5.
《科学通报(英文版)》1996,41(16):1347-1347
In a semicrystalline aggregate of flexible chain polymers, a large amount of the adjacent regularly-folded tiny lamellae coexists with the amorphous phase whose chains have only random spatial arrangement. This 'crystalline-noncrystalline' two-phase model has been widely accepted and used to describe the structure and properties of polymers in condensed state. The crystalline morphology of PE prepared by various methods have been  相似文献   

6.
聚季铵盐絮凝剂的合成及其性能的研究   总被引:1,自引:0,他引:1  
本文以二叔胺与二卤代烃为原料合成了十四种聚季铵盐,讨论了不同原料对缩聚反应以及缩聚物结构对其絮凝性能的影响。通过絮凝效应的测定,探讨了这些聚季铵盐的絮凝特性和Zeta电位变化等。结果表明,对悬浮颗粒的电荷中和是聚季铵盐具有絮凝效应的重要原因之一。聚季铵盐和其它高分子絮凝剂类似,在溶液中对悬浮颗粒也具有架桥作用,因此,聚季铵盐分子量大小对絮凝效果也有一定影响。这类絮凝剂在中性、弱碱性且电解质浓度不高的溶液中絮凝效果较好。聚季铵盐化合物有可能成为具有实际应用价值的一类阳离子型有机絮凝剂。  相似文献   

7.
Multi-colour organic light-emitting displays by solution processing   总被引:13,自引:0,他引:13  
Organic light-emitting diodes (OLEDs) show promise for applications as high-quality self-emissive displays for portable devices such as cellular phones and personal organizers. Although monochrome operation is sufficient for some applications, the extension to multi-colour devices--such as RGB (red, green, blue) matrix displays--could greatly enhance their technological impact. Multi-colour OLEDs have been successfully fabricated by vacuum deposition of small electroluminescent molecules, but solution processing of larger molecules (electroluminescent polymers) would result in a cheaper and simpler manufacturing process. However, it has proved difficult to combine the solution processing approach with the high-resolution patterning techniques required to produce a pixelated display. Recent attempts have focused on the modification of standard printing techniques, such as screen printing and ink jetting, but those still have technical drawbacks. Here we report a class of electroluminescent polymers that can be patterned in a way similar to standard photoresist materials--soluble polymers with oxetane sidegroups that can be crosslinked photochemically to produce insoluble polymer networks in desired areas. The resolution of the process is sufficient to fabricate pixelated matrix displays. Consecutive deposition of polymers that are luminescent in each of the three RGB colours yielded a device with efficiencies comparable to state-of-the-art OLEDs and even slightly reduced onset voltages.  相似文献   

8.
氮唑类金属配合物是含能材料中研究较为广泛的一类材料,其结构易于调控,且具有高能低感的特性。本文选用1,2,4-三氮唑、四氮唑和5-氨基四氮唑这三类配体,与Zn2+、Cd2+、Cu2+等金属离子合成得到系列金属有机骨架结构,并对这些物质进行了热重、差热分析和燃烧热性能测试,结果表明金属离子参与配位后,氮唑类配合物的热稳定性得到了明显增强,其密度也随之增加,而热能数据表明合适的金属离子与含能配体参与配位能有效提高含能配合物的标准摩尔生成焓,金属离子与有机配体的配位聚集程度对生成焓有一定的影响作用,这对今后如何选择合适的金属离子与含能配体进行含能配合物的合成具有指导意义.  相似文献   

9.
无毒防锈颜料亚磷酸-磷酸钾锌经高温处理生成聚合亚磷酸-磷酸钾锌,IR、X-ray、DTA、TGA等测试证实了聚合物的形成.测定了它们的技术指标及漆膜性能、聚合物的防锈性能明显优于亚磷酸-磷酸钾锌.  相似文献   

10.
无毒防锈颜料亚磷酸-磷酸钾锌经高温处理生成聚合亚磷酸-磷酸钾锌,IR、X-ray、DTA、TGA等测试证实了聚合物的形成.测定了它们的技术指标及漆膜性能、聚合物的防锈性能明显优于亚磷酸-磷酸钾锌.  相似文献   

11.
由于过渡金属催化剂在烯烃聚合方面具有高活性和良好的分子剪裁性,通过调节催化荆的微结构或温度、压力等聚合环境的变化,可以在分子层次上实现烯烃聚合物的分子设计与组装,实现聚合物物理性质的调控,最近引起了人们的广泛关注。本文介绍了过渡金属催化荆的合成及其负载化,水相烯烃聚合及活性聚合等方面的研究进展。  相似文献   

12.
聚对苯乙烯撑型超支化共轭聚合物的合成及荧光淬灭研究   总被引:1,自引:1,他引:0  
通过Heck缩聚反应合成了2种以三苯胺为核的"A2 B3"聚对苯乙烯撑型超支化共轭聚合物.通过FT-IR,1HNMR,GPC和TGA等测试对聚合物进行了表征.此类超支化聚合物具有良好的溶解性和热稳定性.通过紫外吸收光谱,荧光发射光谱表征了聚合物的光化学性能,并首次对含硝基芳香烃淬灭其溶液荧光的能力进行了初步研究.此类聚合物不仅合成较为容易,检测的灵敏度也较高,是一类潜在的检测含硝基芳香烃爆炸物的荧光传感器材料.  相似文献   

13.
简单介绍了AgX作为光致变色材料的光致变色机理和其在聚合物中的一些应用方法。  相似文献   

14.
The crystallization of polymers has been one of the major topics in polymer physics. Spherulites are common crystalline structures observed in semi-crystalline polymers. Many studies[1-5] have been performed to investigate the detailed structures and formation mechanisms. It is generally accepted that the three-dimensional geometry of spherulites develops from a stack of lamellae.  相似文献   

15.
制备了一系列St/DVB两网互贯共聚物,并将这些共聚物及其磺酸树脂的物理性能及溶胀性质相互进行比较,结果显示两网之间的重量比对其溶胀性质有很大的影响。  相似文献   

16.
配位聚合物由于其独特的理化性质而备受关注,纳米级配位聚合物更是由于其独特的生物活性等而被广泛应用于生物医药领域.铁酚类配位聚合物由于具有较好的生物兼容性、较强的近红外吸收性以及独特的磁学性能而被广泛研究.因此,本课题组近年来通过白蛋白独特的结构,仿生矿化合成了多种具有纳米结构的铁酚类配位聚合物,研究了其磁共振成像(MRI)、光声成像(PA)以及光热治疗功能,主要概述了白蛋白调控的铁酚类配位聚合物的研究进展,并进一步探讨了该研究工作的方向.  相似文献   

17.
吸水性树脂是一种功能高分子材料,它具有很强的吸水性能。它由低分子物质经聚合合成的高聚物或者由高聚物经化学反应所制成。20世纪70年代后期以来,它的开发取得了巨大进展,在工业、农林业、医疗卫生、日常生活等领域得到广泛应用。本文总结高吸水性树脂的发展历史,应用领域、分类,分析目前高吸水性树脂的研究与开发中存在的问题,阐明木质素基吸水性树脂的研究意义。  相似文献   

18.
增稠剂是水基压裂液中的主要添加剂,关系到压裂液的使用性能及压裂成败。目前使用的聚合物增稠剂品种很多,可分为天然聚多糖及其衍生物与合成聚合物两大类,其中胍胶及其衍生物的应用最广。今后应重点开发具有无残渣、低伤害及耐剪切耐高温等性能的变性淀粉、微生物多糖及合成聚合物。  相似文献   

19.
微生物及胞外多聚物在颗粒污泥形成中的作用   总被引:6,自引:0,他引:6  
黄筱萍  曹郁生 《江西科学》1997,15(4):264-270
集中论述了升流式厌氧污泥床反应器中的微生物学特性,胞外多聚物的组成以及它们在生物膜和颗粒污泥形成中的作用。ECP对颗粒的结构和稳定起重要作用,其含量占颗粒中悬浮性固体含量的0.6%-20%〈主要成分为蛋白质和多糖。甲烷毛状菌属和甲烷八叠球菌属是最初颗粒化和颗粒污泥形成的重要分解乙酸产甲烷的细菌。  相似文献   

20.
叙述了一种新型高分子湿敏材料及其元件的研制.该材料是以吸水性高分子单体与特定高分子单体聚合成一种导电高分子材料,其电阻值随相对湿度呈双曲形变化.用这种材料制成的感湿膜在高湿下不会起皱脱落,有很好的耐水性.该湿敏电阻与一般湿敏电阻不同:对湿度响应呈正特性;因其阻值变化范围相对较小,便于R/V变换;响应速度快,一致性好;在交、直流电压下均可工作  相似文献   

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