碳纤维表面处理

本文主要综述了碳纤维表面性质及表面处理方法,通过表面处理能够达到提高碳纤维复合材料层间剪切强度的目的。     

纤维表面处理对复合材料力学性能的影响

本文研究了碳纤维表面处理方法对纤维-基体界面剪切强度的影响．研究结果表明，相对于未进行表面处詈的碳纤维-所采用的胺基化处理和偶联剂处理两种表面处理方法都能够提高碳纤维界面的剪切强度，从而提高复合材料整体的抗拉强度和弹性模量。并且偶联剂处理方法具有更好的工艺性．     

PBO纤维表面处理对EP/PBO复合材料性能的影响

通过自制的专用处理剂处理聚对苯撑苯并双恶唑(PBO)纤维表面,制备了环氧树脂(EP)/PBO纤维复合材料。通过傅立叶变换红外光谱仪和X射线光电子能谱仪对PBO纤维表面状态进行分析,采用扫描电子显微镜对经过剪切性能测试的NOL环试样破坏面形貌进行分析。结果表明,经过专用处理剂C处理后的PBO纤维表面浸润性得到提高,C、O、N三种元素的含量有较大变化,NOL环试样的剪切强度由文献中报道的15～18 MPa提高到27.83MPa,提高了约59%。     

表面打磨对钛合金/聚氨酯电阻焊接性能的影响

采用砂纸表面打磨及碱溶液腐蚀方式改变车用TB6钛合金表面焊接区域的粗糙度,通过扫描电镜及剪切性能测试研究了表面打磨对TB6钛合金/聚氨酯电阻焊接性能的影响。结果表明,350℃下焊接时间80 s时可获得性能最优接头,此时搭界剪切强度为6.63 MPa。焊接头表面粗糙度1.5μm时凹槽更加明显,宽度为25μm。对焊接头表面打磨处理后,随着粗糙度增加,在钛合金的表面区域形成更大接触角,从而使钛合金表面产生更多处于结合状态的聚氨酯,增大界面结合力,显著提高其力学强度。     

表面处理对三元乙丙橡胶室温粘接性能影响

主要研究了紫外线、臭氧和紫外线 臭氧三种表面处理方法对三元乙丙橡胶室温粘接性能的影响.实验结果表明,当处理时间适当时,粘接试样的拉伸剪切强度均有所提高,其中紫外线处理提高幅度最大,约35%.经扫描电镜,表面光电子能谱分析表明,3种表面处理方法均可在三元乙丙橡胶的表面引入活性基团,改善表面的低活性.     

高性能有机纤维表面等离子体改性研究

在各种纤维表面改性方法中,等离子体改性方法具有操作简单,效率高,节省能源,无公害等特点,是近年来研究的热点.本文综述了各种等离子表面改性技术在高性能纤维表面改性中的应用和研究进展情况,并指出了其进一步的发展趋势.     

碳纤维的电化学氧化表面处理

本文综述了关于碳纤维电化学氧化表面处理的研究现状，碳纤维表面的化学表征，以及处理对碳纤维及其复合材料性能的影响；同时也总结了碳纤维表面处理对于提高碳纤维／树脂复合材料层间剪切强度的解释机理。     

RTV硅橡胶用胶粘剂

航天六院四十六所的王冠英等人以丁腈橡胶、硅树脂、环氧树脂为原料，以聚酰胺200^#树脂为固化剂，制成了双组分胶粘剂；将硅烷偶联剂和含硼化合物在高温下反应，制成表面处理剂。将其用于粘接室温硫化(RTV)硅橡胶硫化胶片与钢、铝合金、碳纤维/酚醛复合材料，     

PAN基碳纤维阳极电解氧化表面处理的研究

借助XPS、力学分析、SEM扫描电镜、傅立叶红外光谱 ,较系统地考察了碳纤维表面组成与结构的变化及阳极氧化表面处理对碳纤维复合材料层间剪切强度的作用与影响。结果表明 :采用碳酸氢铵为电解质对碳纤维进行阳极电解氧化表面处理后 ,其复合材料的层间剪切断裂转变为以张力断裂形式为主 ;通过适当地增加碳纤维表面的羟基含量 ,提高活性碳原子数与非活性碳原子数比 ,可有效地改善碳纤维复合材料的使用性能 ,使碳纤维层间剪切强度提高 49% ,层间剪切强度达 85 .5MPa。     

推广表面毡应用,改善FRP制品外观

玻璃钢表面毡是由定长玻璃纤维经过分散、沉降,然后用胶粘剂粘结而成的一种薄而实的片材,主要用于玻璃钢制品的面层,改善玻璃钢表面性能。根据目前国内玻璃钢生产工艺的不同,表面毡主要可分为三类:手糊型、缠绕型、拉挤型。手糊型玻璃钢表面毡主要适用于手糊玻璃钢制品生产,由于其伏模性好,树脂浸透速度快,使用后能起到掩盖布纹,光洁表面层,提高防老化性能的作用。缠绕型玻璃钢表面毡主要用于缠绕工艺生产的玻璃钢管道及储罐制品,通过其吸收大量的树脂,在制品表面形成丰富的树脂层,提高防渗漏性和耐腐蚀性,从而延长制品本身的使用寿命。拉挤型表面毡用于拉挤生产,可以提高拉挤型材的表面强度,改善外观,避免开裂现象的产生。     

短纤维层间增强碳纤维复合材料层板的力学研究

以斜纹3k T300碳纤维布、环氧树脂和0.3~0.5 mm短切碳纤维为主要实验原料,使用短切纤维铺放装置将短切碳纤维定量铺放在碳纤维布表面,并铺层得到5块层间短切纤维增强的预制体,每块预制体含8层碳纤维布且每块预制体层间短切碳纤维铺放面密度分别为5,10,20,30,40 g/m2,并增设一块层数为8层、层间不含短切纤维增强的预制体作为对照组。采用真空辅助树脂灌注成型方式浸渍预制体后高温固化,得到层间含不同面密度短切纤维的碳纤维复合材料层合板,研究了不同面密度短切纤维含量对碳纤维复合材料层合板拉伸、弯曲以及层间剪切强度的影响。研究结果表明,当短切碳纤维铺放面密度为5 g/m2时,复合材料层板的拉伸、弯曲强度最好,在5~40 g/m2范围内,复合材料层板的层间剪切强度随短切碳纤维铺放面密度的增大而增大。     

PAN基高模碳纤维阳极氧化的表面处理

采用阳极氧化法对PAN基高模碳纤维进行连续表面处理,重点研究了氧化电流密度对碳纤维宏观力学性能、表面形貌、表面酸性官能团以及碳纤维增强树脂基复合材料(CFRP)层间剪切强度(ILSS)的影响。结果表明,电流密度对纤维力学性能、表面形貌影响不大;氧化后纤维表面总的酸性官能团显著提高,最大增幅达13倍左右;适当的处理条件可使CFRP的ILSS从28.4 MPa提高到80 MPa以上。     

Effect of carbon fiber surface functional groups on the mechanical properties of carbon-carbon composites with HTT

The present investigation describes the quantitative measurement of surface functional groups present on commercially available different PAN based carbon fibers, their effect on the development of interface with resol-type phenol formaldehyde resin matrix and its effect on the physico-mechanical properties of carbon-carbon composites at various stages of heat treatment. An ESCA study of the carbon fibers has revealed that high strength (ST-3) carbon fibers possess almost 10% reactive functional groups as compared to 5.5 and 4.5% in case of intermediate modulus (IM-500) and high modulus (HM-45) carbon fibers, respectively. As a result, ST-3 carbon fibers are in a position to make strong interactions with phenolic resin matrix and HM-45 carbon fibers make weak interactions, while IM-500 carbon fibers make intermediate interactions. This observation is also confirmed from the pyrolysis data (volume shrinkage) of the composites. Bulk density and kerosene density more or less increase in all the composites with heat treatment up to 2600 °C. It is further observed that bulk density is minimum and kerosene density is maximum upon heat treatment at 2600 °C in case of ST-3 based composites compared to HM-45 and IM-500 composites. It has been found for the first time that the deflection temperature (temperature at which the properties of the material start to decrease or increase) of flexural strength as well as interlaminar shear strength is different for the three composites (A, B and C) and is determined by the severity of interactions established at the polymer stage. Above this temperature, flexural strength and interlaminar shear strength increase in all the composites up to 2600 °C. The maximum value of flexural strength at 2600 °C is obtained for HM-45 composites and that of ILSS for ST-3 composites.     

Influence of oxygen plasma treatment parameters on the properties of carbon fiber

This study is focused on the impact of oxygen plasma treatment on properties of carbon fibers and interfacial adhesion behavior between the carbon fibers and epoxy resin. The influences of the main parameters of plasma treatment process, including duration, power, and flow rate of oxygen gas were studied in detail using interlaminar shear strength (ILSS) of carbon fiber composites. The ILSS of composites made of carbon fibers treated by oxygen plasma for 1 min, at power of 125 W, and oxygen flow rate of 100 sccm presented a maximum increase of 28% compared to composites made of untreated carbon fibers. Furthermore, carbon fibers were characterized by scanning electron microscopy (SEM), tensile strength test, attenuated total reflectance Fourier transform infrared (ATR-FTIR), and Raman spectroscopy analyses. It was found that the concentration of reactive functional groups on the fiber surface was increased after the plasma modification, as well the surface roughness, which finally improved the interfacial adhesion between carbon fibers and epoxy resin. However, high power and long exposure times could partly damage the surface of carbon fibers and decrease the tensile strength of filaments and ILSS of treated fiber composites.     

电子束辐射接枝对PAN基碳纤维的表面改性

采用电子束加速器辐射接枝方法对聚丙烯腈(PAN)基碳纤维进行表面改性,研究了接枝单体种类对接枝率及其环氧树脂基复合材料力学性能的影响,分析了辐射接枝前后PAN基碳纤维的表面形貌与化学结构以及其复合材料界面断口的形貌变化。结果表明:电子束辐射接枝改性的PAN基碳纤维表面粗糙度增加,表面活性官能团增多,与树脂的机械锲合作用增强,其树脂基复合材料断口表而较为平整;乙二胺/水溶液体系是辐射接枝改性的理想溶液,在200 kGy的电子束辐射下,PAN基碳纤维表面的接枝率为6.66%,复合材料的层间剪切强度提高了45.1%。     

Microstructure and interlaminar shear property of carbon fiber-SiC nanowire/pyrolytic carbon composites with SiC nanowires growing at different positions

In order to improve the interlaminar shearing strength of carbon fiber/pyrolytic carbon (Cf/PyC) composites, SiC nanowires (SiCNWs) growing at different positions were introduced into carbon fiber/pyrolytic carbon composites to generate carbon fiber-SiC nanowire/pyrolytic carbon (Cf-SiCNWs/PyC) composites. Cf-SiCNWs/PyC composites were prepared by sol-gel and isothermal chemical vapor infiltration (ICVI) method. The morphology, microstructure and compositions of composites were investigated by SEM, TEM, XRD and XPS. The interlaminar shearing strength was tested and the effect of SiCNWs growth positions on the interlaminar shearing strength was investigated. The results showed that SiCNWs were consisted of perfect single crystalline structure of β-SiC with diameter of 160–200 nm. The SiCNWs could grow at four kinds of positions to combine with carbon fibers to form multi-scaled reinforcements (micro-scaled carbon fibers and nanoscaled SiCNWs). The interlaminar shear strength of Cf-SiCNWs/PyC composites were increased by 78% compared with Cf/PyC composites without SiCNWs. The improvement of interlaminar shear strength was attributed to bridging and pull-out of multi-scaled reinforcements composed of carbon fibers and SiCNWs as well as the enhancement of fiber/matrix interface bonding generated by SiCNWs growing at different positions.     

A study of the effect of oxygen plasma treatment on the interfacial properties of carbon fiber/epoxy composites

In this work, effects of the interface modification on the carbon fiber‐reinforced epoxy composites were studied. For this purpose, the surface of carbon fibers were modified by oxygen plasma treatment. The surface characteristics of carbon fibers were studied by X‐ray photoelectron spectroscopy (XPS), atomic force microscopy (AFM), dynamic contact angle analysis (DCAA), and dynamic mechanical thermal analysis (DMTA), respectively. The interlaminar shear strength (ILSS) was also measured. XPS and AFM analyses indicated that the oxygen plasma treatment successfully increased some oxygen‐containing functional groups concentration on the carbon fiber surfaces, the surface roughness of carbon fibers was enhanced by plasma etching and oxidative reactions. DCAA and DMTA analyses show that the surface energy of carbon fibers increased 44.9% after plasma treatment for 3 min and the interfacial bonding intensities A and α also reached minimum and maximum value respectively. The composites exhibited the highest value of ILSS after oxgen plasma treated for 3 min. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2010     

臭氧处理对碳纤维表面及其复合材料性能的影响

利用X射线光电子能谱(XPS)研究了碳纤维经臭氧(O3)氧化处理后表面元素组成及表面官能团的变化，结果发现，O3表面处理主要增加了碳纤维表面上的羟基或醚基官能团；研究了表面O3氧化处理对复合材料力学性能的影响，结果表明，碳纤维经O3氧化处理后明显改善了碳纤维与环氧树脂间的界面粘结，其复合材料的层间剪切强度明显提高。     

Novel application of chitosan: ameliorative effect of homogeneous and floccular chitosan on the interfacial property of carbon fiber/epoxy resin composites

A novel homogeneous floccular chitosan was directly grafted onto carbon fiber surface by a simple and controllable method. Scanning electron microscopy (SEM), single fiber strengths and interlaminar shear strength (ILSS) have been applied to characterize the fiber and the interface bonding. Compared with raw carbon fibers, the chitosan-treated ones demonstrate significant increases in the surface roughness and wettability. Particularly, about 21.21% increase in the mechanical properties of composites was obtained, which is attributed to good adhesion between functional carbon fiber and resin matrix in the interlaminar regions, as revealed by fracture surfaces.