粗糙度对碳纤维/聚芳基乙炔复合材料界面性能的影响

采用二氧化碳超临界(scCO2)处理碳纤维(CF)表面的方法,研究了粗糙度对碳纤维/聚芳基乙炔(PAA)树脂复合材料界面性能的影响.处理前后的碳纤维通过XPS,AFM和表面能测量进行了表征.CF/PAA复合材料的界面力学性能通过层间剪切强度测试(ILSS)与断口形貌分析进行了评价.结果表明,scCO2处理前后碳纤维表面的化学组成基本上没有变化.随着碳纤维表面粗糙度的增加,CF/PAA复合材料的界面力学性能先增加后减小.其中粗糙度范围为30～45 nm的样品有最高的ILSS值,43.36MPa,比未处理的样品提高了44%.对复合材料的ILSS提高起主要作用的因素是碳纤维与PAA树脂的界面齿合作用.而齿合作用程度的不同主要是由于不同粗糙度而引起的碳纤维表面物理状态的不同.     

Effect of plasma modification on the mechanical properties of carbon fiber/phenolphthalein polyaryletherketone composites

A study was carried out to investigate the effect of plasma modification on the mechanical properties of carbon fiber/phenolphthalein polyaryletherketone composites. The influence of oxygen plasma treatment on the surface properties of carbon fibers was investigated by X‐ray photoelectron spectroscopy and atomic force microscopy. The results indicated that oxygen plasma treatment was capable of increasing the concentrations of the oxygen‐containing groups of the carbon fiber surface as well as enhancing surface roughness. Both the chemical bonding and mechanical interlocking gave rise to an increase of the interlaminar shear strength of composite. Scanning electron microscope photographs showed that the destruction mode of composites was changed after the carbon fibers were treated by oxygen plasma. The results also indicated that the flexural properties of plasma‐treated carbon fiber composites were improved. POLYM. COMPOS., 2013. © 2013 Society of Plastics Engineers     

表面处理对碳纤维润湿性及连续纤维增强PEEK复合材料拉伸性能的影响

用5种工艺对碳纤维进行表面处理,并与PEEK薄膜热压成复合材料。采用润湿天平法检测碳纤维表面的润湿力并进行SEM表面形貌分析;测试试样拉伸性能并观察试样断口形貌。结果表明:混酸超声处理法处理的碳纤维表面粗糙度最大,润湿性最好,表面润湿力达到0.82mN,用其制备复合材料的拉伸性能最佳。     

碳纤维改性HA/PMMA生物复合材料力学性能的研究

采用原位合成与溶液共混相结合的方法,制备了短切碳纤维增强纳米羟基磷灰石(HA)/聚甲基丙烯酸甲酯(PMMA)生物复合材料。研究了碳纤维的含量和长度对HA/PMMA复合材料结构和力学性能的影响。采用万能材料试验机和扫描电子显微镜对复合材料的力学性能及断面的微观形貌进行了测试和表征。结果表明:碳纤维在HA/PMMA复合材料中分布均匀,有效提高了复合材料的力学性能;碳纤维含量为4%时,复合材料的拉伸强度、弯曲强度、压缩强度和弹性模量等均达到最大值;复合材料的断裂伸长率随碳纤维含量的增加而减小;当碳纤维含量一定时,随其长度的增加,复合材料的拉伸强度、弯曲强度和弹性模量均增加,但断裂伸长率降低。     

Relationship Between Some Mechanical Strengths of CFRP and Interfacial Properties

The relationships between microscopic properties such as interfacial shear strength (IFSS) and macroscopic properties such as flexural strength were investigated for CFRP prepared from carbon fiber and epoxy resin. Flexural, tensile and impact strengths all went through maximum values when plotted against the surface treatment time of the carbon fiber. The flexural strength of CFRP as a function of the treatment time of the carbon fiber behaved similarly to the adhesive strength of the resin and carbon fiber. Also, the results indicated that the bahavior of tensile and impact strengths varied with the treatment time in much the same way as the interfacial shear strength did. The occurrence of these two types of macroscopic and microscopic property effects can be understood by taking into account the chemical activity and roughness of the carbon fiber surface.     

Recycling carbon fiber from composite waste and its reinforcing effect on polyvinylidene fluoride composite: Mechanical,morphology, and interface properties

Recycled carbon fiber (RCF) was reclaimed from thermoset composite waste and employed as reinforcement from 0 to 30 wt% to prepare polyvinylidene fluoride (PVDF)/RCF composite. Commercial virgin carbon fiber (VCF) was used as comparison. The surface morphology, chemistry, and tensile properties of carbon fibers were investigated by Scanning Electron Microscopy (SEM), X‐Ray Photoelectron Spectroscopy (XPS), and tensile test. Results showed that the roughness, O/C ratio and –COO content of RCF surface were significantly improved after recycling. In addition, the single fiber tensile strength and modulus of RCF was lower than that of VCF. The interfacial adhesion between RCF and PVDF was much stronger due to the high chemical activity and roughness over the RCF surface. Mechanical properties of composites were investigated by flexural test, impact test, and Dynamic Mechanical Analysis (DMA). It is found that the PVDF/RCF composite showed higher flexural properties, storage modulus, and lower impact strength, which indicated the strong interfacial adhesion, played an important role in reinforcing. The morphology of fracture further demonstrated the strong interface in PVDF/RCF composite. The fiber length distribution and crystallinity of composites were also evaluated to characterize the composites. The work develops potential for recycling and reuse of carbon fiber, and also expands the application of PVDF based composite. POLYM. COMPOS., 38:2544–2552, 2017. © 2015 Society of Plastics Engineers     

短切纤维增强改性磷酸盐水泥抗折性能研究

分别采用短切碳纤维和短切玻璃纤维对磷酸盐水泥进行了增强改性研究.采用羧甲基纤维素溶液做分散剂使短切纤维在水泥基体中得到了很好的分散;通过凝结时间及抗折强度测试,研究了纤维种类与掺量对磷酸盐水泥性能的影响.结果表明,短切纤维的加入对磷酸盐水泥的凝结时间影响不明显;两种短切纤维的加入都使磷酸盐水泥的抗折强度显著提高,磷酸盐...     

表面处理对可生物降解黄麻/PLA复合材料结构和性能的影响

采用注塑成型法制备了生物降解黄麻短纤维增强PLA复合材料,通过力学性能测试及SEM,探讨了碱处理、碱和硅烷偶联剂KH550同时处理对复合材料结构和性能的影响。结果表明:两种处理方法均能够增加黄麻纤维的表面粗糙度,但碱和偶联剂KH550同时处理的效果要优于碱处理,且KH550改善了黄麻短纤维与PLA树脂之间的界面黏结性能提,高了黄麻/PLA复合材料的拉伸强度和弯曲强度。     

粗糙度对碳纤维布增强聚丙烯力学性能影响

为了研究粗糙度对碳纤维布增强聚丙烯力学性能的影响。通过打磨的方式制作出有着不同表面粗糙度的聚丙烯试件并在其试件上粘贴相同几何尺寸、相同数量的碳纤维布,同时在制作试件的过程中注重对涂刷胶层厚度的控制,制作出15个试件,进行了A,B,C三组拉伸实验。实验结果表明:粗糙度对碳纤维布增强聚丙烯拉伸性能的提高有着显著的影响,B,C组实验结果表明在相同的试验力下,粗糙度数值在0.141~2.751的范围内递增时,试件抗变形能力逐渐增强,试件的变形量逐渐减小。同时随着粗糙度数值的递增,实验中的试验力位移曲线在试验力0.5~0.6 kN的范围内线形斜率数值由0.61增长到5.61,且提升幅度也随着粗糙度的增加逐渐增大。     

碳纤维表面生长纳米管及其效果的研究进展

碳纤维表面生长碳纳米管(CNTs),将性能优异的纳米材料与碳纤维有机结合,能够增加碳纤维表面粗糙度,有效改善复合材料界面粘合性能,是一种新型碳纤维表面处理技术。本文对碳纤维表面生长碳纳米管的制备方法以及界面增效效果的国内外研究现状进行了综述,分析了不同制备方法的优缺点以及各自的增强效果,探讨了研究过程中存在的问题,展望了该方法的研究趋势和前景。     

碳纤维表面性能对界面黏结强度的影响浅析

为了解碳纤维表面性能对纤维-树脂界面黏结强度的影响,使用扫描电镜、原子力显微镜与X射线光电子能谱仪(XPS),对国产T-300级碳纤维、台丽TC36S碳纤维、东丽T700S碳纤维的表面进行物理与化学表征,得出:国产碳纤维与TC36S碳纤维表面形貌相近,而T700S表面比较光滑;XPS定量分析技术表明3种碳纤维表面的活性差异较大,碳纤维与树脂的界面黏结强度随纤维粗糙度和表面活性官能团而变化。     

Effect of fiber chemical treatment of nonwoven coconut fiber/epoxy composites adhesion obtained by RTM process

In this work untreated and alkali treated nonwoven coconut fiber mats/epoxy resin composites were manufactured using the resin transfer molding process. The alkaline solution removes some impurities present on fibers superficial layers and the effect regarding fiber/matrix adhesion were investigated by thermogravimetric analysis, dynamic mechanical analysis (DMA), scanning electron microscopy (SEM), ultrasonic C‐scan, and quasi‐static flexural test. Results show a removing of some amorphous fibers constituents, mainly waxes, extractives, and hemicellulose, revealing the fiber roughness surface but no initial degradation temperature changing. Regarding the composites, a similar interfacial adhesion was observed in both one through the results of SEM, DMA and quasi‐static flexural tests. The conclusion is that chemical treatment conditions applied on the fiber surface was been suitable to improve fiber roughness but did not the adhesion between coconut fibers mat and epoxy resin. POLYM. COMPOS., 38:2518–2527, 2017. © 2015 Society of Plastics Engineers     

碳纤维长度以及添加量对碳化硅网状多孔陶瓷性能的影响

为提高有机泡沫浸渍法制备的碳化硅网状多孔陶瓷的抗折强度,采用碳纤维对碳化硅网状多孔陶瓷进行增强。研究了添加剂和碳纤维对碳化硅陶瓷浆料流变性能和触变性能的影响以及碳纤维长度和添加量对试样微观结构、气孔率、耐压强度、抗折强度的影响。结果表明:当分散剂-FS20添加量为0.1%(质量分数),增稠剂-CMC添加量为0.1%(质量分数),粘结剂-CL添加量为0.05%(质量分数)时,碳化硅陶瓷浆料的流变性能和触变性能达到最佳,碳纤维的加入增加了浆料的粘度;另外,随着碳纤维添加量和长度的增加,试样的抗折强度呈现先增大后减小的变化趋势。当碳纤维长度为1 mm且添加量为0.75%(质量分数)时,试样抗折强度达到最大。     

碳纤维布/玻纤布增强聚氨酯复合材料的研究

以聚氨酯为基体树脂,分别以碳纤维布、玻璃纤维布和这两种纤维布交替铺叠作为增强材料,采用真空辅助灌注成型工艺制备了4种复合材料.考察了纤维布的铺层结构对复合材料的弯曲、拉伸和冲击性能的影响.结果显示,复合材料的拉伸模量和弯曲模量随碳纤维含量增加而增加,冲击强度则降低.分别采用TGA、DMA和SEM对复合材料的热性能、界面...     

碳纳米管定向排列增强碳纤维/环氧树脂复合材料制备及力学性能

采用高频电场诱导法制备了碳纳米管定向有序填充的碳纤维/环氧树脂复合材料。研究了电场频率对复合材料力学性能的影响规律,对复合材料的显微形貌进行观察。结果表明:在富树脂区碳纳米管沿着电场方向存在明显的有序排列现象;高频电场诱导后复合材料的层间剪切强度最大提高28.9%,压缩强度提高28.83%,弯曲强度提升15.01%,断口粗糙度增加,树脂与碳纤维的界面结合状态改善。     

硅灰对碳纤维混凝土强度及电阻率影响研究

通过在碳纤维混凝土中加入硅灰,研究了硅灰对碳纤维混凝土抗压强度、抗折强度和劈裂强度的影响规律,同时研究了硅灰对碳纤维混凝土电阻率的影响作用。结果表明:碳纤维混凝土相对素混凝土,抗压强度降低了5.9%,抗折强度提高了25.8%,劈裂强度增加了了21.1%;加入硅灰后,碳纤维混凝土抗压强度、抗折强度和劈裂强度都有所增加;10%硅灰掺量时,抗压强度增加了39%,抗折强度提高了40.6%,劈裂强度提高了34.3%。加入硅灰后碳纤维混凝土电阻率也明显降低,3 d时两者电阻率降低了8.6Ω,随着时间的推移,差值越来越小。说明硅灰对碳纤维混凝土的电阻率也有明显作用,进一步证明了加入硅灰可以有效提高碳纤维在混凝土中的分散性。     

EP/BMI树脂基碳纤维复合材料的制备与性能表征

以环氧树脂(EP)、双马来酰亚胺(BMI)、4,4’-二氨基二苯砜(DDS)和短切碳纤维(SCF)等为主要原料制备了EP/BMI/DDS/SCF复合材料,并研究了SCF添加量对复合材料力学性能和热性能的影响。结果表明,当SCF添加量为0.25 %(质量分数,下同)时,EP/BMI/DDS/SCF复合材料的力学性能提高最大,其拉伸强度、弯曲强度、弯曲模量和缺口冲击强度比未添加SCF时的EP/BMI/DDS复合材料分别提高了48.52 %、32.15 %、25.77 %以及150.91 %;此外,SCF的加入有助于提高复合材料的热性能。     

The Effect of Arylboronic Acid Treatment of Carbon Fiber on the Mechanical and Tribological Properties of PA66 Composites

PA66 composites filled with surface-treated carbon fiber were prepared by twin-screw extruder in order to study the influence of carbon fiber surface arylboronic acid treatment on the mechanical and tribological behavior of the PA66 composites (CF/PA66). The mechanical property, friction and wear tests of the composites with untreated and treated carbon fiber were performed and the worn surface morphology was analyzed. The results show that the worn surface area of the treated carbon fiber was far smoother than that of the untreated carbon fiber and there formed a bonding adhesion on the carbon fiber surface after treatment. The tensile strength of CF/PA66 composites with surface arylboronic acid treatment was improved. The friction coefficient and wear of arylboronic acid treated CF/PA66 composites were apparently lower than that with untreated carbon fiber. In conclusion, the surface treatment favored the improvement of the higher interface strength and so had good effect on improving the tribological properties of the composites.     

Preparation of multiscale graphene oxide‐carbon fabric and its effect on mechanical properties of hierarchical epoxy resin composite

Graphene oxide (GO) was used to modify the surface of carbon fiber layers through electrophoretic deposition, forming a multiscale reinforcement fabric. By adjusting the experimental parameters, the resulting GO‐carbon fabric showed productive and homogenous distribution of thin and less‐agglomerate GO platelets on carbon fiber surface, remarkably enlarging the surface area and roughness of carbon fabric. To investigate the effect of GO sheets on composites, GO‐carbon fabric and carbon fabric‐reinforced hierarchical epoxy resin composites were respectively manufactured. Mechanical tests demonstrated that after introducing GO flakes on carbon fabric, both the flexural strength and interlaminar shear strength of composite had achieved an increase, especially the interlaminar shear strength rising by 34%. Through fractography analysis, it was found that in pure carbon fabric‐reinforced epoxy composite, the fiber/matrix debonding fracture mechanism predominated, while after the GO decoration on carbon fiber surface, the composite featured a stronger interfacial bonding, leading to the enhancement in mechanical properties of hierarchical epoxy resin composite. POLYM. COMPOS., 37:1515–1522, 2016. © 2014 Society of Plastics Engineers     

Effect of surface treatment of pitch-based carbon fiber on mechanical properties of polyethernitrile composites

The effect of surface treatment of pitch-based carbon fiber on a new engineering thermoplastic resin, polyethernitrile, was investigated. Pitch-based carbon fiber (CF) was treated in two separate oxidizing solutions. In the first method, a nitric acid solution was used as an oxidizing agent. In the second method, a hydrogen peroxide solution was used. Both methods demonstrated that each of these solutions was a satisfactory oxidizing agent for the pitch-based CF. These treated fibers were combined with polyethernitrile polymer by the powder impregnation method, and unidirectional laminates were obtained. Improvements in both interlaminar shear strength and transverse flexural strength were achieved. The laminates fabricated from the treated CF maintained the same longitudinal flexural strength as laminates from the untreated control. In addition, scanning electron micrographs of composite fracture surfaces also showed excellent bonding of the treated fiber.