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1.
汪海平  容敏智  章明秋 《化学进展》2010,22(12):2397-2407
微胶囊填充型自修复聚合物及其复合材料是近年来高分子科学界的研究热点之一。本文介绍了含有微胶囊聚合物复合材料自修复的概念和机理,综述了近5年来针对不同基体材料的微胶囊自修复研究情况,包括环氧树脂、乙烯基酯树脂、纤维增强环氧树脂复合材料、弹性体以及聚甲基丙烯酸甲酯等基体材料。本文同时介绍了微胶囊的芯材和壁材、微胶囊的粒径、修复时间和压强等因素对复合材料自修复性能的影响,以及自修复效果的评价方法。最后对微胶囊填充型自修复聚合物及其复合材料的研究前景进行了展望。  相似文献   

2.
This paper is an overview of current understanding in the areas of composites made from biodegradable thermoplastics and wood fillers. The review finds that the composite properties depend on the type of wood filler, the choice of polymer matrix, the wood filler content, the compatibilization technique used and the processing parameters. The extent of interfacial adhesion and the filler morphology are identified as the underlying factors that control the composite properties. Future research needs are identified, including establishment of fundamental relationships between quantified interfacial adhesion and end-use properties and advanced modelling of biodegradation processes.  相似文献   

3.
The autonomic self-healing materials based on microcapsules have made major advancements for the repairing of microcracks in polymers and polymer composite systems. Self-healing encapsulated materials have the inborn ability to heal polymeric composites after being damaged by chemical and mechanical progressions. These intelligent micro-encapsulated self-healing materials possess great capabilities for recovering the mechanical as well aesthetic properties and barrier properties of the polymeric structures. Based on real world observations and experimental data, it is believed that microcracks and microcracking in polymeric materials can result because of many chemical and physical routes and is one of the foremost critical issues for polymeric materials. Especially in polymeric coatings, these microcracks can lead towards disastrous failure, and conventional healing systems like patching and welding cannot be used to repair microcracks at such a micro-level. Self-healing materials, especially, capsule based self-healing materials is a new field sought as an alternative to the conventional repairing techniques, requiring no manual intrusion and uncovering. This review covers the basic and major aspects of the microencapsulated self-healing approach like the effect of synthesis parameters on the size of microcapsules, healing efficiency determination, and the potential of the existing developed microencapsulated agents.  相似文献   

4.
Hypercrosslinked polymers (HCPs) represent a class of nanoporous materials with a wide range of practical and potential applications such as gas sorption and separation, heterogeneous catalysis, drug delivery, and chromatographic separation. First introduced by Davankov and Tsyurupa in the early 1970s, HCPs have developed rapidly over the past few decades. Mostly based on Friedel-Crafts chemistry, HCP materials can be prepared from the post-crosslinking of polystyrene-type precursors in their swollen state, or from the condensation of small building blocks. HCP materials manifest numerous important advantages, including moderate synthetic conditions, an enormous stockroom of inexpensive monomers, robust structures, and good thermal and chemical stabilities. This review article aims to provide an overview of recent publications on HCPs, and the emphasis is positioned on the synthetic approaches, theoretical studies, characterizations, structure-property relationships, and applications of these HCP materials.  相似文献   

5.
含液晶聚合物的原位复合材料中界面相容性的改善策略   总被引:4,自引:0,他引:4  
综述了近年来含液晶聚合物的原位复合材料中增容技术的一些进展,主要了四种增容技术,即加入具有增容作用的第三组分;在分散相液晶聚合物的主链上引入与基体树脂主链中相同或相似的单元,酯交换反应和多元共混技术,简要描术字原位复合材料的发展趋势。  相似文献   

6.
Intrinsically conducting polymers (ICP) and conductive fillers incorporated conductive polymer-based composites (CPC) greatly facilitate the research in electromagnetic interference (EMI) shielding because they not only provide excellent EMI shielding but also have advantages of electromagnetic wave absorption rather than reflection. In this review, the latest developments in ICP and CPC based EMI shielding materials are highlighted. In particular, existing methods for adjusting the morphological structure, electric and magnetic properties of EMI shielding materials are discussed along with the future opportunities and challenges in developing ICP and CPC for EMI shielding applications.  相似文献   

7.
Abstract

This review paper provides an overview of chromogenic polymers and their classifications, mechanisms, chemistry, synthesis procedures, and potential applications with a focus on packaging. Commonly and academically accepted classifications derived from chemical engineering, material science, and packaging science are used. Furthermore, recent progress and outputs aligned with chromogenic polymers for overcoming the common challenges are discussed. Finally, future prospects, market trends and academic investigations are described, including challenges related to chromogenic polymers.  相似文献   

8.
When dealing with smart polymers, in particular with shape memory polymers, the polymer type and composition specify the overall material properties and in particular the extent of the shape memory effect. Polybenzoxazines as a polymer with high potential for structural applications represent a promising component for materials with both shape memory effect and structurally interesting material properties. This minireview gives insight into how the shape memory effect, in particular the shape recovery event, is influenced by internal factors such as polymer structure, morphology and external factors such as filler addition.  相似文献   

9.
The concept of using crack propagation in polymeric materials to control drug release and its first demonstration are reported. The composite drug delivery system consists of highly‐textured superhydrophobic electrosprayed microparticle coatings, composed of biodegradable and biocompatible polymers poly(caprolactone) and poly(glycerol monostearate carbonate‐co‐caprolactone), and a cellulose/polyester core. The release of entrapped agents is controlled by the magnitude of applied strain, resulting in a graded response from water infiltration through the propagating patterned cracks in the coating. Strain‐dependent delivery of the anticancer agents cisplatin and 7‐ethyl‐10‐hydroxycamptothecin to esophageal cancer cells (OE33) in vitro is observed. Finally the device is integrated with an esophageal stent to demonstrate delivery of fluorescein diacetate, using applied tension, to an ex vivo esophagus.  相似文献   

10.
评价了热致液晶高聚物作为高性能成型材料的特点。综述了由增强性的热致液晶高聚物和热塑料聚合物基体组成的原位复合材料及其制备、结构和性能。也讨论了今后研究这一塑料增强新途径时要注意的诱导取向和相容性。  相似文献   

11.
Abstract

At present we have strong evidence that several members of a series of wholly-aromatic, para-linked, rodlike polyamides, polyesters, and polyesteramides form molecular composites with certain flexible-chain, thermoplastic polymers over a wide range of compositions. This paper reports on the initial results of an investigation of intermolecular interactions using spectroscopy and various scattering techniques as well as characterization of some of the mechanical and optical properties of these materials. The composites are made by two techniques: 1) photo-polymerization of a homogeneous solution of a rodlike polymer in a monomer containing a photoinitiation; 2) solvent evaporation from homogeneous solutions of very limited combinations of solvent, rodlike polymers and flexible polymers. While both of these techniques produce optically clear, nonscattering films of various thicknesses over the entire compositional range, e.g., 1–99 wt% of rodlike polymer, the latter is generally more convenient and has been used extensively in this study. Optical and electron microscopy, wide angle light scattering, and spectroscopic and thermal analysis support the view that these polymer combinations are truly molecularly dispersed.  相似文献   

12.
With the rapid development of communication technology in civil and military fields, the problem of electromagnetic radiation pollution caused by the electromagnetic wave becomes particularly prominent and brings great harm. It is urgent to explore efficient electromagnetic wave absorption materials to solve the problem of electromagnetic radiation pollution. Therefore, various absorbing materials have developed rapidly. Among them, iron (Fe) magnetic absorbent particle material with superior magnetic properties, high Snoek’s cut-off frequency, saturation magnetization and Curie temperature, which shows excellent electromagnetic wave loss ability, are kinds of promising absorbing material. However, ferromagnetic particles have the disadvantages of poor impedance matching, easy oxidation, high density, and strong skin effect. In general, the two strategies of morphological structure design and multi-component material composite are utilized to improve the microwave absorption performance of Fe-based magnetic absorbent. Therefore, Fe-based microwave absorbing materials have been widely studied in microwave absorption. In this review, through the summary of the reports on Fe-based electromagnetic absorbing materials in recent years, the research progress of Fe-based absorbing materials is reviewed, and the preparation methods, absorbing properties and absorbing mechanisms of iron-based absorbing materials are discussed in detail from the aspects of different morphologies of Fe and Fe-based composite absorbers. Meanwhile, the future development direction of Fe-based absorbing materials is also prospected, providing a reference for the research and development of efficient electromagnetic wave absorbing materials with strong absorption performance, frequency bandwidth, light weight and thin thickness.  相似文献   

13.
超分子聚合物复合材料定义为纤维、填料等增强体均匀分散在超分子聚合物基体中的复合材料。根据超分子聚合物与增强体之间化学键连接的不同可分为三种类型:(1)无化学键;(2)共价键;(3)非共价键。超分子聚合物复合材料与分子聚合物复合材料共同组成了完整的聚合物复合材料体系。本文综述可自愈合的氢键、π-π堆叠和金属配位型超分子聚合物复合材料的研究进展。  相似文献   

14.
Molecular imprinted polymers are custom made materials with specific recognition sites for a target molecule. Their specificity and the variety of materials and physical shapes in which they can be fabricated make them ideal components for sensing platforms. Despite their excellent properties, MIP-based sensors have rarely left the academic laboratory environment. This work presents a comprehensive review of recent reports in the environmental and biomedical fields, with a focus on electrochemical and optical signaling mechanisms. The discussion aims to identify knowledge gaps that hinder the translation of MIP-based technology from research laboratories to commercialization.  相似文献   

15.
Self-healing polymer composites possess the inherent ability to heal the damage event autonomically or non-autonomically with external intervention. These advanced materials can be commercialized if the challenges and limitations of different self-healing mechanisms are well known and considered. These include capsule-based healing systems, vascular healing systems, and intrinsic healing systems. To date, most of the reviews have studied and reported on different self-healing mechanisms including their response to impact, fatigue, and corrosion tests. This review focuses mostly on extrinsic and intrinsic self-healing polymer composites which have been reported during the past five years by comparing their healing efficiency, advantages, and challenges in the prospect of their future development as well as their possible applications across various industries such as aerospace, automobile, coating, electronics, energy, etc.  相似文献   

16.
炭/导电聚合物复合材料是近年来发展起来应用于超级电容器的一种新型电极材料。炭材料与氧化物的复合材料,或者炭材料与导电聚合物的复合材料,能够将双电层电容与法拉第电容结合,既可提高超级电容器的比电容,改变其充放电电压,又可提高其循环性能。本文综述了近年来国内外各种炭材料,如活性炭,碳纳米管等与导电聚合物复合材料的研究进展,认为炭与导电聚合物的复合材料,尤其是性能优良的炭气凝胶,模板法制备的中孔炭,以及由金属或非金属碳化物与氯气等刻蚀剂反应制备的骨架炭与导电聚合物的复合材料是超级电容器电极材料研究的一个重要发展方向。  相似文献   

17.
热塑性树脂的增强:从原位复合材料到原位混杂复合材料   总被引:8,自引:0,他引:8  
何嘉松 《高分子通报》1997,(4):197-202,237
综述了两类增强的热塑性树脂的基本方面。一类是由原位形成的热致液晶聚合物微纤增强的原位复合材料。从实验上研究了获得有效增强效果的两个关键因素;致热液晶聚合物的基体树脂中的成纤,以及在液晶聚合物与基体树脂不相容共混物中的增容作用。另一类是由作者发明的原位混杂复合材料,这一类材料是用直径在两个数量级上的纤维和原位形成的微纤混杂增强的。  相似文献   

18.
Inverse vulcanization provides dynamic and responsive materials made from elemental sulfur and unsaturated cross-linkers. These polymers have been used in a variety of applications such as energy storage, infrared optics, repairable materials, environmental remediation, and precision fertilizers. In spite of these advances, there is a need for methods to recycle and reprocess these polymers. In this study, polymers prepared by inverse vulcanization are shown to undergo reactive compression molding. In this process, the reactive interfaces of sulfur polymers are brought into contact by mechanical compression. Upon heating these molds at relatively low temperatures (≈100 °C), chemical bonding occurs at the polymer interfaces by S−S metathesis. This method of processing is distinct from previous studies on inverse vulcanization because the polymers examined in this study do not form a liquid phase when heated. Neither compression nor heating alone was sufficient to mold these polymers into new architectures, so this is a new concept in the manipulation of sulfur polymers. Additionally, high-level ab initio calculations revealed that the weakest S−S bond in organic polysulfides decreases linearly in strength from a sulfur rank of 2 to 4, but then remains constant at about 100 kJ mol−1 for higher sulfur rank. This is critical information in engineering these polymers for S−S metathesis. Guided by this insight, polymer repair, recycling, and repurposing into new composites was demonstrated.  相似文献   

19.
Composites of unmodified or oxidized carbon nano‐onions (CNOs/ox‐CNOs) with poly(3,4‐ethylenedioxythiophene):poly(styrenesulfonate) (PEDOT:PSS) are prepared with different compositions. By varying the ratio of PEDOT:PSS relative to CNOs, CNO/PEDOT:PSS composites with various PEDOT:PSS loadings are obtained and the corresponding film properties are studied as a function of the polymer. X‐ray photoelectron spectroscopy characterization is performed for pristine and ox‐CNO samples. The composites are characterized by scanning and transmission electron microscopy and differential scanning calorimetry studies. The electrochemical properties of the nanocomposites are determined and compared. Doping the composites with carbon nanostructures significantly increases their mechanical and electrochemical stabilities. A comparison of the results shows that CNOs dispersed in the polymer matrices increase the capacitance of the CNO/PEDOT:PSS and ox‐CNO/PEDOT:PSS composites.  相似文献   

20.
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