共查询到20条相似文献,搜索用时 125 毫秒
1.
2.
晶须增强增韧聚合物基复合材料机理研究进展 总被引:21,自引:0,他引:21
简介了晶须增强增韧聚合物基复合材料研究的现状;并较全面地介绍了各种增强增韧机理,主要包括:裂纹桥接、裂纹偏转、拔出效应等机理。晶须增强增韧聚合物基复合材料主要表现在:(1)晶须导致基体局部应力状态改变;(2)晶须对基体结晶行为产生影响。文中还简要介绍了在实验过程中影响聚合物基晶须复合材料性能的几个重要的因素,如与界面相关的一系列因素和晶须在基体中含量、晶须在基体中的分散程度、晶须长径比以及在基体中的排列方向等。 相似文献
3.
玻璃纤维增强乙烯基酯树脂复合材料的增韧 总被引:8,自引:0,他引:8
聚合物基复合材料的增韧一直是高分子材料领域研究的热点之一.文中从乙烯基酯树脂基体增韧、乙烯基酯树脂/玻璃纤堆界面改性及增强材料结构和形式的优化三个方面对玻璃纤堆增强乙蜂基酯树脂复合材料的增韧进行了综述,介绍了各种增韧方法的机理和增韧效果,对这些增韧方法进行了评述.并分析了今后的发展方向. 相似文献
4.
5.
综述了纤维增强热固性聚合物基复合材料(PMC)层间增韧的最新研究进展。热固性复合材料由于基体树脂高的交联密度而呈脆性,表现出低的冲击损伤阻抗和损伤容限特征。柔性聚合物层间增韧是改善聚合物基复合材料层间断裂韧性和抗冲击性的有效手段,且不会降低热固性树脂的热性能和高模量。目前有3种层间增韧方法:颗粒增韧、聚合物纤维增韧和薄膜增韧。讨论了3种方法的概念、实施方案、增韧机理及研究成果。最后重点阐述了创新性的复合材料“离位”增韧思想,介绍了具有全部自主知识产权的“离位”复合材料高性能化技术体系,包括预浸料和液态成型两大复合材料产品系列。 相似文献
6.
7.
《中国粉体工业》2016,(1)
环氧树脂具有优异的力学性能、耐腐蚀、易加工等特点,应用领域非常广阔,但其具有较大的脆性、较弱的耐冲击性等缺点,限制了其进一步的发展。近年来,高性能环氧树脂基复合材料成为了学者们的热点研究课题。本文从环氧树脂的增韧、耐热、增强三个方面对高性能环氧树脂基复合材料的现状进行了阐述,其中增韧方面重点介绍了橡胶增韧、热塑性树脂增韧、超支化聚合物增韧、含柔性链段固化剂增韧、互穿网络聚合物增韧、纳米填料增韧、热致液晶聚合物增韧等方法;耐热方面重点介绍了增加基材官能度、引入耐热刚性基团、有机硅改性、POSS改性等方法;增强方面重点介绍了碳纤维增强、玻璃纤维增强、碳纳米管增强、其他纤维增强等方法。最后对目前存在的问题和未来的发展方向进行了展望。 相似文献
8.
9.
插层法制备聚合物/粘土纳米复合材料及其应用进展 总被引:8,自引:0,他引:8
概述了聚合物/粘土纳米复合材料插层制备的新进展,根据插层机理和方法的差别,将插层法分为三类:(1)单体插层复合;(2)溶液中聚合物插层复合;(3)熔融聚合物插层复合。重点提出了利用双螺杆挤出机制备聚合物基纳米复合材料的新方法,展望了聚合物/粘土纳米复合材料的开发及其应用前景。 相似文献
10.
11.
A mixed micromechanics model was developed to predict the overall electrical conductivity of carbon nanotube (CNT)–polymer nanocomposites. Two electrical conductivity mechanisms, electron hopping and conductive networks, were incorporated into the model by introducing an interphase layer and considering the effective aspect ratio of CNTs. It was found that the modeling results agree well with the experimental data for both single-wall carbon nanotube and multi-wall carbon nanotube based nanocomposites. Simulation results suggest that both electron hopping and conductive networks contribute to the electrical conductivity of the nanocomposites, while conductive networks become dominant as CNT volume fraction increases. It was also indicated that the sizes of CNTs have significant effects on the percolation threshold and the overall electrical conductivity of the nanocomposites. This developed model is expected to provide a more accurate prediction on the electrical conductivity of CNT–polymer nanocomposites and useful guidelines for the design and optimization of conductive polymer nanocomposites. 相似文献
12.
Polymer clay nanocomposites (PCN) exhibit improved mechanical properties due to nanolevel dispersion of clay in the polymer
matrix. They also exhibit good tribological performance under dry sliding conditions. Abrasive wear behaviour of these materials
would be different from dry sliding behaviour as the mechanisms of the both are entirely different. Hence the abrasive wear
behaviour of these materials needs to be investigated. The abrasive wear characteristics of polyamide 6 nanocomposites, with
1, 3 and 5% (wt.) clay prepared by melt intercalation technique, under two-body abrasive wear conditions have been reported.
Abrasive wear tests were conducted using a pin-on-disc tribometer containing an abrasive counterface. All the polyamide nanocomposites
investigated exhibited a low abrasive wear resistance compared with pristine Nylon. The wear performance of the nanocomposites
was correlated with the mechanical properties. Dominant ploughing and cutting wear were observed in polymer clay nanocomposites.
The amount of clay present alters the wear mechanism. 相似文献
13.
Danumah C Ray SS Kaliaguine S Bousmina M 《Journal of nanoscience and nanotechnology》2006,6(2):523-529
Understanding the optimal processing conditions for the fabrication of polymer nanocomposites is of fundamental importance in designing materials with balance of properties. To understand these conditions in the case of maleic anhydride grafted polypropylene (PP-g-MA)/layered mesostructured silica (LMS) nanocomposites, the effect of temperature, shear rate, and residence time during processing on the structure of the nanocomposites were studied. The results showed that the combination of temperature, residence time, and mechanical shears have strong effect on the structure of the nanocomposites, rather than just interfacial interactions between the polymer matrix and silicate layers. However, interfacial interactions between the polymer matrix and silicate layers primarily play an important role to the intercalation of polymer chains into the silicate galleries. On the basis of our experimental results, a first explanation of the formulation mechanism of PP-g-MA/LMS nanocomposites is proposed. Finally, a general concept of processing conditions for manufacturing of polymer nanocomposites by melt-compounding process in a batch-mixer is described. 相似文献
14.
More than 10 years have passed since carbon nanotubes (CNT) have been found during observations by transmission electron microscopy (TEM). Since then, one of the major applications of the CNT is the reinforcements of plastics in processing composite materials, because it was found by experiments that CNT possessed splendid mechanical properties. Various experimental methods are conducted in order to understand the mechanical properties of varieties of CNT and CNT-based composite materials. The systematized data of the past research results of CNT and their nanocomposites are extremely useful to improve processing and design criteria for new nanocomposites in further studies. Before the CNT observations, vapor grown carbon fibers (VGCF) were already utilized for composite applications, although there have been only few experimental data about the mechanical properties of VGCF. The structure of VGCF is similar to that of multi-wall carbon nanotubes (MWCNT), and the major benefit of VGCF is less commercial price. Therefore, this review article overviews the experimental results regarding the various mechanical properties of CNT, VGCF, and their polymer nanocomposites. The experimental methods and results to measure the elastic modulus and strength of CNT and VGCF are first discussed in this article. Secondly, the different surface chemical modifications for CNT and VGCF are reviewed, because the surface chemical modifications play an important role for polymer nanocomposite processing and properties. Thirdly, fracture and fatigue properties of CNT/polymer nanocomposites are reviewed, since these properties are important, especially when these new nanocomposite materials are applied for structural applications. 相似文献
15.
Xu W Raychowdhury S Jiang DD Retsos H Giannelis EP 《Small (Weinheim an der Bergstrasse, Germany)》2008,4(5):662-669
Poly(lactide-co-glycolide) (PLG), a biocompatible and biodegradable polymer, is dramatically toughened by adding small amounts of surface modified clay nanoparticles. The elongation during tensile tests increases from 7% for the pure polymer to 210% for the nanocomposite, accompanied with a modest increase in modulus. In contrast, PLG nanocomposites based on fumed silica treated with hexamethyldisilazane show only modest improvements in toughness. Electron microscopy, X-ray scattering, rheometry, and dielectric relaxation spectroscopy are used to investigate the toughening mechanism. Multiple crazing occurs in the clay nanocomposite after yielding. Small angle X-ray scattering studies show significant orientation of the clay nanoparticles along the tensile stress direction during deformation. The clay nanocomposites show a new, slow relaxation mode, most likely due to interfacial adsorbption of PLG chains on the surface of the clay nanoparticles. The dramatic increase in toughness is attributed to physical crosslinks introduced by the clay nanoparticles, a mechanism absent in the PLG/silica nanocomposites. The physical crosslinks increase the brittle fracture strength of the polymer and, consequently, trigger a toughening mechanism via multiple crazing and shear yielding. 相似文献
16.
Nanocomposites 总被引:7,自引:0,他引:7
D Chakravorty 《Bulletin of Materials Science》1992,15(5):411-420
Nanocrystalline metals having sizes of the order of a few nanometres dispersed in an oxide glass matrix have been discussed
in this review. The various physical and chemical routes developed so far for synthesizing such materials have been described.
The different physical properties, especially optical, electrical and magnetic behaviour of these nanocomposites have been
delineated. The physical mechanisms which give rise to these characteristics are discussed. 相似文献
17.
18.
综述了聚合物基石墨烯及改性石墨烯纳米复合材料的研究进展.添加少量的石墨烯就可以显著提聚合物材料的各方面性能,因此,近年来石墨烯得到了学术界和工业界的高度关注,石墨烯、氧化石墨烯的改性,以及聚合物基石墨烯纳米复合材料被广泛研究.通过广泛的文献阅读对聚合物基石墨烯纳米复合材料的结构、制备方法以及性能进行了深入探讨. 相似文献
19.
K. A. Malini M. R. Anantharaman S. Sindhu C. N. Chinnasamy N. Ponpandian A. Narayanasamy M. Balachandran V. N. Sivasankara Pillai 《Journal of Materials Science》2001,36(4):821-824
Magnetic nanocomposites containing iron oxide particles embedded in a polymer matrix have been synthesized using the method of ion exchange. They have been characterized by using low temperature and room temperature magnetic measurements and Mössbauer spectroscopy. The iron content in these samples has also been determined. The results have been analysed and explained. The physical and chemical properties of these nanocomposite materials are different from those of the bulk. Some of the unique properties of these materials find application in information storage, color imaging, ferrofluids and magnetic refrigeration. 相似文献
20.