碳纳米材料接枝碳纤维的复合材料界面增效研究进展

界面作为复合材料的重要组成部分,起着传递载荷的作用,影响复合材料的整体性能。碳纤维表面属于石墨乱层结构,微晶有序取向,惰性大,不易与树脂基体结合。对碳纤维进行适当的表面改性,增加纤维的比表面积、粗糙度和引入活性官能团,都能改善表面润湿情况,实现机械结合和化学结合,提高复合材料的界面性能。碳纳米材料接枝到碳纤维表面,是提高界面性能的有效方法之一。因此,对碳纳米管、氧化石墨烯接枝碳纤维的制备方法、界面增效设计以及界面增强机制的国内外研究现状进行综述和分析,在此基础上,展望了碳纳米材料接枝碳纤维表面和界面性能评价方法的研究趋势和前景。     

碳纳米管改性环氧树脂/碳纤维复合材料的界面性能

采用碳纳米管对环氧树脂体系以及碳纤维进行改性处理,得到四种试样,即CNTs-00 (不添加碳纳米管)、CNTs-01 (碳纳米管与活性分子预反应)、CNTs-02 (碳纳米管与树脂体系直接混合)、CNTs-03 (碳纤维表面生长碳纳米管)。采用视频接触角测量仪以及界面性能测试仪对树脂浸渍国产T800S碳纤维单丝形成的微球形态、微球与纤维的界面接触角及界面剪切强度(IFSS)等进行了分析表征;同时采用模压法制备了复合材料单向板,从宏观尺度表征了其层间剪切强度(ILSS)。结果表明,与CNTs-00相比,CNTs-01的树脂界面浸润性以及复合材料IFSS有了较大提高,接触角减小了3.1°,IFSS提高了12.7%,ILSS提高了9%;CNTs-02的树脂界面浸润性略有降低,接触角增大了0.9°,IFSS降低了8.6%,ILSS与CNT–00基本相同;CNTs-03的界面浸润性降低,浸润角增大了4.5°,IFSS降低了5.7%,ILSS降低了11.5%。     

塑料市场

表面改性提升碳纤维界面性能中科院宁波材料技术与工程研究所复合材料研究团队日前在碳纤维表面改性方面取得进展。研究人员将氧化石墨烯引入环氧基上浆乳液中,采用浸渍法对碳纤维进行表面改性,可以有效调控碳纤维复合材料的界面微观结构,进而显著改善碳纤维复合材料的界面性能。这一成果为制备高性能碳纤维复合材料提供了一种新的方法和思路。研究结果表明,氧化石墨烯均匀分散在碳纤维表界面层中,改性碳纤维复合材料的界面剪切强度比未上浆和未改性的材料,分别提高了70.9%和36.3%,     

碳纳米材料修饰碳纤维及其复合材料界面性能的研究进展

碳纤维/树脂复合材料（CFRC）具有质轻高强的优点,广泛应用在航空航天、体育器材、新能源汽车等领域。然而,碳纤维表面呈化学惰性,其与树脂间的界面结合性较差,使CFRC的力学性能受到限制,碳纤维的表面改性已成为增强CFRC的发展趋势。文章介绍碳纳米管、石墨烯、炭黑等不同维度的碳纳米材料修饰碳纤维及其增强CFRC界面性能的研究进展,并深入分析了碳纳米材料对CFRC的界面增强效果、作用机理及关键影响因素,对CFRC改性研究的发展方向及研究前景进行展望。     

ZnO纳米棒提高碳纤维增强树脂基复合材料界面性能

碳纤维增强树脂基复合材料因其高的比强度和比模量,在航空航天等领域被广泛地应用。目前,碳纤维与树脂的界面性能是制约复合材料性能的关键因素。通过简单的水热法,在碳纤维表面合成了ZnO纳米棒阵列。在不同的生长时间下,制备了具有不同长度的ZnO纳米棒。ZnO纳米棒改性之后树脂对碳纤维的浸润性能明显提高。同时,复合材料的界面剪切强度得到明显提升,最大增幅达到了28.4%。通过扫描电子显微镜观测了单丝拔出后碳纤维的表面形貌,结果表明:改性碳纤维单丝拔出后表面粗糙而且残留了断裂的树脂基体,进一步证明碳纤维表面生长ZnO纳米棒之后界面强度得到改善。     

含碳纳米管上浆剂上浆改性碳纤维及其界面研究

碳纤维(CF)是一种高强度、高模量的高性能纤维,被广泛应用于复合材料中,但是纤维表面的活性官能团含量低,与基体之间的界面结合性能较差。本文利用含氨基化碳纳米管(NH_2-CNTs)上浆剂对光威GQ4922/12K型碳纤维表面进行改性,改善碳纤维与环氧树脂之间的界面结合性能。通过傅里叶红外光谱、扫描电镜、X射线光电子能谱、接触角和微脱粘对改性后的纤维表面组成、表面形貌、表面自由能和界面剪切强度进行分析,发现NH_2-CNTs可成功接枝到碳纤维表面,改性后纤维表面的氧(氮)元素含量增加,与水接触角从67.1°降低到50.5°,表面自由能从32.2 mN/m增加到了41.1 mN/m;界面剪切强度在氨基化碳纳米管质量浓度为0.6%时达到最大,相比未改性纤维从62.3 MPa提高到76.8 MPa,提高了23.3%。结果表明通过在上浆剂中引入氨基化碳纳米管,可以增加碳纤维表面活性,提高碳纤维与基体树脂的界面结合性能。     

碳纳米管及功能化碳纤维增强环氧树脂复合材料的制备方法

正本发明涉及一种碳纳米管及功能化碳纤维增强环氧树脂复合材料的制备方法。本发明将碳纳米管经过羧基化功能化后,在碳纳米管上引入二元胺或多元胺,得到表面胺基化的碳纳米管;将胺基化的碳纳米管与表面经过羧基化的碳纤维反应,得到胺基化的碳纤维表面接枝有碳纳米管,在碳纤维表面引入二元胺或多元胺,使碳纤维表面未完全与     

碳纳米管及功能化碳纤维增强双马来酰亚胺树脂复合材料的制备方法

正本发明涉及一种碳纳米管及功能化碳纤维增强双马来酰亚胺树脂复合材料的制备方法。本发明将碳纳米管经过羧基化功能化后,在碳纳米管上引入二元胺或多元胺,得到表面胺基化的碳纳米管;将胺基化的碳纳米管与表面经过羧基化的碳纤维反应,得到胺基化的碳纤维表面接枝有碳纳米管,在碳纤维表面引入二元胺或多元胺,使碳纤维表面未完全与胺基化的碳纳米管反应的羧基充分胺基化,     

碳纳米管-水泥基复合材料的力学性能和微观结构

研究了掺碳纳米管水泥砂浆的力学性能和微观结构,并与掺碳纤维水泥砂浆的性能进行了对比。低含量的碳纳米管-水泥复合材料具有良好的抗压强度和抗折强度。用扫描电镜对碳纳米管-水泥复合材料以及碳纤维-改性水泥复合材料的微观结构进行了分析。结果表明：复合材料中碳纳米管表面被水泥水化产物包裹,同时碳纳米管水泥砂浆的结构密实。碳纤维表面光滑,在碳纤维与水泥石之间存在明显裂缝。孔隙率测试结果表明碳纳米管的掺入改善了材料的孔结构。     

碳纳米管/碳纤维混杂多尺度增强体研究现状

碳纳米管(CNTs)优异的力学性能使其成为复合材料的理想增强材料,将CNTs引入到碳纤维(CF)表面制备CNTs/CF纳、微米复合增强体,可同时改善复合材料的界面剪切强度和冲击强度,从而获得具有优异综合性能的复合材料。本文综述了CNTs/CF混杂多尺度增强体的制备方法及其复合材料的性能。     

碳纳米管在炭纤维表面的可控自组装

采用催化化学气相沉积法将碳纳米管(CNTs)原位生长于炭纤维(CF)表面并自组装成不同形貌的CNTs/CF杂化结构。使用扫描电子显微镜、拉曼光谱仪对制备的纳米/微米杂化结构进行微观形貌分析和结构表征。结果显示,随着温度的升高,碳纳米管在炭纤维表面由均匀分布状态转变为取向生长状态,并且长度及石墨化程度均不断增加。结合碳纳米管结构参数的变化,使用纳米悬臂梁模型解释了这一杂化结构的形成机理。模型分析表明,杂化结构的形貌转变是由不同温度下在炭纤维表面生长的碳纳米管的结构参数不同所造成的,因此可以通过调整相关结构参数控制碳纳米管在炭纤维表面的自组装过程。     

Tailoring Carbon Fiber/Carbon Nanotubes Interface to Optimize Mechanical Properties of Cf‐CNTs/SiC Composites

C_f/SiC composites were fabricated using fiber coatings including CNTs and matrix infiltration using the polymer impregnation and pyrolysis process. Interface between fiber and CNTs (CF/CNTs) was tailored to optimize mechanical properties of hybrid composites. The tailored interphases, such as Pyrocarbon (PyC) and PyC/SiC, protect fibers from degradation during the growth of CNTs successfully. Hybrid composites with well‐tailored CF/CNTs interface displayed significantly increased mechanical strength (352 ± 21 MPa) compared with that (34 ± 3 MPa) of composites reinforced with CNTs, which grown on carbon fibers directly. The interfacial bonding strength of hybrid composites was improved and optimized by tailoring the CF/CNTs interface. Interfacial failure modes were studied, and a firm interface bonding at the joint where CNTs grown was observed.     

Improved tribological properties of polyimide composites by micro–nano reinforcement

The hydroxylate carbon nanotubes (CNTs) were grafted by chemical method on the surface of the oxidized carbon fibers (CF) to improve the mechanical and tribological properties of polyimide (PI). The microstructure and fracture surface of the polyimide composites indicated that CF–CNTs hybrid as a multiscale reinforcement can distribute into the PI matrix homogeneously. Tribo-tests further showed that CF–CNTs hybrid had a better effect on hardness increment, impact strength enhancement, friction reduction, and wear resistance. Compared to the neat PI, the friction coefficient and wear rate of CF–CNTs/PI composite deceased by 23.2 and 55.9%, respectively. In particular, the loading capacity and high speed resistance of CF–CNTs/PI composite were greatly improved. The corresponding wear mechanisms were also discussed by observing the worn surface of the PI composites. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019 , 136, 47900.     

Effect of electrochemical anodization and growth time on continuous growth of carbon nanotubes on carbon fiber surface

Carbon nanotubes (CNTs)/carbon fiber (CF) reinforcements were prepared by chemical vapor deposition after electrochemical anodization and catalyst impregnation. The results showed that after the electrochemical anodization, the CFs were oxidatively etched and the surface roughness increased, which is helpful to form a uniform catalyst coating on the surface of CF. Under the current of 0.4 A and 0.6 A, CNTs can grow evenly on the surface of CF. Within a certain range, with the increase of growth time, the density and length of CNTs are improved. The CNTs/CF reinforcement prepared at the current intensity of 0.4 A and the growth time of 8 min has the best comprehensive performances compared with other as-fabricated samples. The tensile strength of the sample can reach a high value of 4.56 GPa, and the wettability of resin has an effective improvement.     

High improvement of interfacial and mechanical properties in reinforced PP composite by grafting polyethyleneimine modified carboxylic multi-walled carbon nanotubes on short carbon fiber

The properties of carbon fiber reinforced polymer composites (CFRPs) will benefit greatly from improving interfacial performance. In this study, the interfacial properties of the PEI-CNT-CF/PP composite was improved by coating polyethyleneimine (PEI) modified carboxylic multi-walled carbon nanotubes (CNTs) in aqueous solution (PEI-CNT) onto the surface of the CF (PEI-CNT-CF) to form a network structure. The network formation changed the chemical characteristics and compatibility of CF surface by introducing amine (imine) groups, and could induce transcrystallization (TC) at interface of composite. These positive factors led to a 24.6% increasement in the interfacial shear strength (IFSS) of PEI-CNT-CF/PP, and further resulted in 16.2% and 5.3% improvement in tensile and flexural strength, respectively. SEM images of the fracture surface demonstrated a significant improvement in the interfacial adhesion between PEI-CNT-CF and PP resin. These results indicated that the PEI-CNT was a great choice to strengthen the interface of CF/PP system.     

Catalyst optimization and reduction condition of continuous growth of carbon nanotubes on carbon fiber surface

Carbon nanotubes (CNTs)/carbon fiber (CF) reinforcements were synthesized under different catalyst compositions and reduction conditions. The effects of the catalyst, reduction temperature and reduction time on the surface morphology, graphitization, and single filament tensile strength of the prepared CNTs/CF samples were investigated. When nickel was used as the catalyst and copper as the catalyst promoter, with the increase of copper concentration, the catalytic activity increased. Thus, the carbon source was consumed more completely, improving the abundance of CNTs with good graphitization. And the effect of repairing CF defects was more obvious, hence the single filament tensile strength accordingly increased. Besides, the increase of catalyst reduction temperature and reduction time intensified the etching of CF by catalyst, and decreased the single filament tensile strength of CF. With the deposition of CNTs, the tensile strength of CF was enhanced in varying degrees. When the concentration of cooper was 0.01 mol/L with the reduction time of 10 min and reduction temperature of 450 °C, CNTs/CF had the highest tensile strength, which can reach up to 4.51 GPa. We determined that bimetallic catalysts could adjust the catalytic activity of nickel. The change of reduction time and temperature would affect the quality of CNTs, which was helpful to obtain high quality CNTs on CF surface and improve the mechanical properties of CNTs/CF and its composites.     

Effect of carbon nanotubes grown temperature on the fracture behavior of carbon fiber reinforced magnesium matrix composites: Interlaminar shear strength and tensile strength

The design of an interfacial structure is particularly important for load transfer in composites. In this paper, different amounts of carbon nanotubes (CNTs) were grafted onto the carbon fiber (CF) surface by adjusting grown temperature using injection chemical vapor deposition (ICVD). The prepared CF preform grafted with CNTs (CNTs-CF) were used to reinforce magnesium alloy by squeeze casting process. The microstructures were analyzed by means of optical microscope (OM) and scanning electron microscope (SEM), and the interlaminar shear strength (ILSS) and tensile strength of the composites were determined by double-notch shear test and tensile test. The results indicated that moderate ILSS was more conducive to improving the tensile properties of carbon fiber reinforced magnesium matrix (C_f/Mg) composites. Compared with C_f/Mg, the tensile strength of composite with CNTs increased by about 80%. For C_f/Mg composites grafted with CNTs, CNTs had the effects of delaying crack propagation and increasing energy consumption by the pull-out and bridging mechanism, which were the main reasons for improving the strength. The analysis of shear fracture surface showed that the crack propagation path can be optimized by adjusting the amounts of grafted CNTs. The presence of CNTs affects the stress distribution and consequently the crack initiation as well as the crack propagation.     

聚丙烯腈基碳纤维用环氧树脂上浆剂的比较

用两种环氧树脂上浆剂对国产聚丙烯腈基碳纤维进行上浆,测试和比较了两种环氧树脂上浆剂对聚丙烯腈(PAN)基碳纤维耐磨性、与水接触角、表面能等性能以及拉伸强度、伸长率、层间剪切强度(ILSS)等力学性能的影响。上浆剂中主体成分环氧树脂相对分子质量不是影响碳纤维层间剪切强度的决定性因素。     

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.