CF表面处理对PA66/CF复合材料性能的影响

以10%碳纤维(CF)增强尼龙66(PA66)为实验对象,采用液相酸化法和自制PA上浆剂两种方法对CF进行表面处理,实验了不同处理方法对CF表面状态的影响,用红外光谱测试了不同处理后的官能团,并分析测试了CF表面状态对PA66/CF复合材料微观结构与力学性能的影响。实验结果表明,在混合酸溶液中加入过硫酸铵可以有效地提高CF表面酸化速率。自制的PA上浆剂使CF表面活性基团密度提高,改善了与PA66基体的相容性,其界面微观结构有所改善,结合强度有所提高。由此制备的PA66/CF复合材料,拉伸强度由115 MPa提高到162 MPa,提高了40.87%。冲击强度由7.8 kJ/m2提高到了11.2 kJ/m2,提高了43.59%。     

表面处理碳纤维改性聚酰亚胺复合材料的机械性能

采用硅烷偶联剂KH-550、高温氧化和超声波+偶联剂复合方法(简称超声复合方法)分别对碳纤维(CF)进行表面处理,制备不同表面处理的CF改性热塑性聚酰亚胺(PI)复合材料,研究表面处理CF对CF/PI复合材料力学和摩擦磨损性能的影响,利用扫描电子显微镜对PI复合材料磨损表面进行观察。结果表明:与纯PI相比,CF的加入提高了PI复合材料的机械性能,经超声复合处理的CF的增强效果较好;磨损表面表明:超声复合处理CF改性PI复合材料磨损表面的犁沟和磨屑较少,且平整。     

CF表面处理对SLS用PA12/CF复合材料性能的影响

利用热空气处理法和浓硝酸处理法分别对碳纤维(CF)进行表面处理,然后与尼龙(PA)12粉末按量比3∶7通过机械混合法制备PA12/CF复合粉末材料。将复合粉末材料进行注塑成型,考察了热处理温度及浓硝酸处理时间对复合材料力学性能和热性能的影响。结果表明,浓硝酸处理时间为1 h处理效果最好,与未处理的CF复合材料相比,注塑样条拉伸强度提高23%,弯曲弹性模量提高133%,维卡软化点提高6.2℃;扫描电子显微镜分析表明,经过热处理后的CF在PA12基体中分散均匀,两者的界面相容性良好。     

碳纤维增强尼龙66复合材料的制备及性能

采用双螺杆挤出机熔融共混法制备了碳纤维(CF)增强尼龙66复合材料(PA66/CF),对其结构进行了表征,并研究了其力学性能。扫描电镜照片显示,在PA66/CF复合材料中,CF与PA66基体充分粘结在一起,其微观形貌表明,体系中碳纤长度为0.5~0.7 mm。力学性能测试发现,与尼龙66相比,PA66/CF复合材料各项力学性能指标均有大幅度提高。当加入4束碳纤维时,PA66/CF复合材料力学性能最佳,该复合材料的拉伸强度为200.2 MPa,与PA66相比提高了113.2 MPa;弯曲强度为280.2 MPa,比PA66提高了190.3 MPa;弯曲模量为13560.8 MPa,比PA66提高了10628.7 MPa;冲击强度为14.8 kJ/m^2,比与PA66提高了6.3 kJ/m^2。该PA66/CF复合材料密度较小、力学性能优良,可以广泛应用于风电叶片、发动机罩盖、仪表盘、车尾门等产品当中。     

钛酸钾晶须和硫酸钙晶须增强PA66/PVDF的摩擦学行为研究

制备了钛酸钾晶须（PTW）和硫酸钙晶须（CSW）增强聚酰胺66（PA66）/聚偏氟乙烯（PVDF）复合材料,通过摩擦磨损试验机研究了不同含量晶须对PA66/PVDF摩擦磨损性能的影响,并采用扫描电子显微镜、傅里叶变换外光谱仪观察了复合材料的微观结构、磨损表面和转移膜形貌。结果表明,PTW的加入使得共混物的自润滑性与耐磨性均降低,CSW有效地提高了PA66/PVDF的摩擦学性能;摩擦前后复合材料表面并未发生化学变化。     

碳纤维增强尼龙复合材料的性能研究

研究了碳纤维(CF)用量及助剂对碳纤维/PA66复合材料性能的影响。结果表明:复合材料的拉伸强度随着CF用量增加而增大,当CF质量分数超过15%时,增幅缓慢。在同一载荷下,随CF用量的增加,复合材料的摩擦系数先降低后升高,碳纤维质量分数为20%时,复合材料体系的摩擦系数最小,较PA66树脂降低了1/3;相容剂、耐磨助剂的加入,可有效改善CF/PA66复合材料的摩擦磨损性能。     

PA66/胺基化碳纳米管复合材料薄膜的制备及表征

对多壁碳纳米管进行胺基化处理后,用溶液共混法制备了PA66/多壁碳纳米管复合材料,研究了碳纳米管的加入对PA66电学性能、热稳定性能、结晶行为的影响。复合材料薄膜的渗流阈值出现在碳纳米管质量分数为3%～4.5%,胺基化碳纳米管质量分数为4%时,已基本构成完整的导电网络,体积电阻率和表面电阻率均降低了8个数量级。碳纳米管的加入提高了复合材料的热稳定性能。碳纳米管在复合材料中充当了成核剂,提高了PA66的成核速度,但降低了其结晶总速度。     

电化学氧化处理对碳纤维及EP复合材料性能的影响

利用电化学氧化法对碳纤维（CF）进行表面改性处理,并将改性CF用于改性环氧树脂（EP）,研究了CF处理前后纤维复丝拉伸强度和EP／CF复合材料的力学性能。结果表明,氧化处理改善了CF与基体的粘结性;经电化学氧化处理后CF的表面羟基含量提高39．96％,羧基／酯基含量提高141．06％,活性碳原子数增加34．28％;随着氧化电流密度的增加,CF复丝的拉伸强度和复合材料的层间剪切强度均呈现先增大后减小的变化趋势,当电流密度为0．2A／m^2时,复合材料的层间剪切强度提高31．70％。     

不同方法处理碳纤维增强PTFE复合材料性能的研究

采用两种不同的方法对碳纤维(CF)表面进行处理,一种是先以热空气对CF进行氧化处理,然后用偶联剂进行表面处理;另一种是先用聚四氟乙烯(PTFE)乳液对CF进行浸渍,后用等离子体进行表面处理。研究了不同方法、不同表面处理条件对PTFE/CF复合材料拉伸性能的影响,并应用扫描电镜对拉伸断口形貌进行了分析。结果表明,两种方法都能有效地提高CF与PTFE之间的界面结合力及PTFE/CF复合材料的拉伸性能。     

CF/CNTs多尺度混杂填充PA6复合材料性能研究

以碳纤维/碳纳米管(CF/CNTs)多尺度混杂填充聚酰胺6(PA6)复合材料为研究对象,采用不同的方法处理CNTs,并考察了对应复合材料的力学性能、导电性能和导热性能。结果表明:CNTs经过表面化学镀镍处理后,明显改善了CF与基体界面间的结合强度和相容性。表面镀镍处理的碳纳米管(CNTs-Ni)吸附在CF表面,不仅可促进CF与基体间形成"钉扎效应",从而提高了复合材料的力学性能,还在CF与PA6基体间形成了导热桥路和导电网络,使材料的电阻率和界面热阻有所下降;CF和CNTs混杂填充基体树脂对复合材料的力学性能、导热性能及导电性能有着良好的协同增效作用;CNTs-Ni可明显改善CF增强复合材料的导热性能和导电性能。     

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.     

短切碳纤维增强尼龙66复合材料研究进展

碳纤维的表面处理和尼龙的改性以及各种碳纤维/尼龙基复合材料的制备是当前研究热点之一。与纯尼龙相比,碳纤维的加入使材料表现出更优异的力学和摩擦学性能,拓展了尼龙高技术领域的应用空间。概述了碳纤维/尼龙66复合材料的制备方法、结构及性能方面研究进展,并提出了相关研究方向,为今后提高碳纤维增强尼龙66基复合材料力学性能和摩擦学性能研究提供参考。     

Friction and wear mechanisms of PA66/PPS blend reinforced with carbon fiber

The mechanical and tribological properties of carbon fiber (CF) reinforced polyamide 66 (PA66)/polyphenylene sulfide (PPS) blend composite were studied in this article. It was found that CF reinforcement greatly increases the mechanical properties of PA66/PPS blend. The friction coefficient of the sample decreases with the increase of CF content. When CF content is lower (below 30%), the wear resistance is deteriorated by the addition of CF. However, the loading of higher than 30% CF significantly improves the tribological properties of the blend. The lowest friction coefficient (0.31) and the wear volume (1.05 mm³) were obtained with the PA66/PPS blend containing 30% CF. The transfer film and the worn surface formed by sample during sliding were examined by scanning electron microscopy. The observations revealed that the friction coefficient of PA66/PPS/CF composite depends on the formation and development of a transfer film on the counterface. The abrasive wear caused by ruptured CFs (for lower CF content) and the load bearing ability of CFs (for higher CF content) are the major factors affecting the wear volume. In addition, the improvements of mechanical properties, thermal conductivity, and self‐lubrication of bulk CFs are also contributed to the wear behavior of PA66/PPS/CF composite. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci 2007     

聚酰胺66改性玻璃纤维增强聚苯硫醚体系的摩擦学性能研究

研究了聚酰胺66(PA66)改性玻璃纤维(GF)增强聚苯硫醚(PPS)（PPS/PA66/GF）复合体系的摩擦因数、磨损体积、磨损后表面的微观形貌及损耗因子峰值、储能模量对摩擦因数的影响。结果表明,PA66的加入显著改善了复合材料的摩擦学性能,当PA66含量为40 %（质量分数,下同）时,磨损最小,为5.24 mm3,相对于PPS+30 %GF(13.60 mm3)下降了61 %;扫描电镜分析磨损表面,随着PA66含量的增加,磨损机理由磨粒磨损转为粘着磨损;复合材料损耗因子峰值越大,摩擦因数越小;初始储能模量越大,摩擦因数越小。     

体育器材用CFRPA6复合材料的制备及其性能

采用碳纤维(CF)改性聚酰胺(PA)6,从而获得PA 6/CF复合材料。结果表明:CF被浓硝酸氧化后,表面会引入碳氮、碳氧等极性基团,增加了PA 6与CF的界面反应活性;CF经浓硝酸处理后表面有许多沟槽出现,增大的表面积对PA 6与CF间机械锁合有利;随着浓硝酸处理CF时间的延长,复合材料的悬臂梁缺口冲击强度略有提高,拉伸强度提高较大;CF被过度氧化时,复合材料的缺口冲击强度、拉伸强度均降低;经浓硝酸氧化处理后,增强了CF界面黏结效果,CF被PA 6紧密包覆,断裂时两者有黏结现象发生;未经浓硝酸处理的样条在纤维拔出后会留下大量空洞,经浓硝酸处理后CF表面极性基团增加,提高了CF与基体树脂的黏结强度。     

Influence of surface modification of carbon nanotube on microstructures and properties of polyamide 66/multiwalled carbon nanotube composites

The melt‐mixing polyamide 66 (PA66) composite samples that incorporated pure, acid‐ and amine‐functionalized multiwalled carbon nanotubes (MWCNTs) were prepared in order to enhance mechanical and frictional properties of PA66 composites. The homogeneous dispersion of amine‐functionalized MWCNTs (D‐MWCNTs) in PA66 matrix was observed from the significantly uniform morphology of tensile fractured surface of the composites. Differential scanning calorimetry measurement indicates that D‐MWCNTs acted as effective nucleation agent for PA66 matrix and the crystallinity of PA66 was increased. The fracture stress and tensile modulus of the composites were significantly improved with the incorporation of D‐MWCNTs, owing to the good dispersion of D‐MWCNTs. Compared with PA66, the PA66 composites with 1.0 wt% D‐MWCNTs were improved considerably in both wear and friction properties owing to the change of the tribological mechanisms. The good dispersion of D‐MWCNTs in PA66 and good interface compatibility between D‐MWCNTs and PA66 favored the formation of a thin layer on the contact surfaces during wear and friction test, which played an important role in reducing wear and friction of the composite and in suppressing the transverse cracks. These results prove the importance of D‐MWCNTs in a positive change of the mechanical and frictional properties of PA66 composites and suggest the applicability prospect of PA66/D‐MWCNTs composites in engineering components.POLYM. COMPOS., 2013. © 2013 Society of Plastics Engineers     

The Mechanical and Tribological Properties of Anodic Oxidation Treatment Carbon Fiber-Filled PU Composite

The interfacial adhesion of the carbon fiber (CF) reinforced polyurethane (PU) composite was improved by the means of anodic oxidation treatment. The mechanical and reciprocating sliding wear properties were studied and results showed that the anodic oxidation treatment have definitely improved the mechanical strength. And the wear and the friction coefficient of PU decreased with the addition of CF. The friction coefficients of anodic oxidation treated CF/PU composites are lower than those of PU and CF/PU composite. The interfacial adhesion between the CF and PU dominated the main wear mechanisms.     

碳纤维/聚芳基乙炔复合材料界面改性方法的研究

为了改善碳纤维/聚芳基乙炔复合材料的界面性能,采用表面氧化、表面接枝、偶联剂、表面涂层等方法对碳纤维进行表面处理,探讨了各种方法对非极性聚芳基乙炔树脂基复合材料的界面改性效果。研究表明,纤维表面氧化处理后有利于碳纤维/聚芳基乙炔复合材料界面性能的改善,在此基础上通过表面接枝及表面偶联剂处理在纤维表面引入可与基体树脂发生反应的基团,可以达到非极性树脂基复合材料界面改性的目的。极性的高碳酚醛树脂可以更好地浸润氧化后的纤维表面,并且与聚芳基乙炔树脂在结构上相似,因此作为涂层处理纤维表面后可以明显提高材料的界面性能,该方法适于进行3D织物的改性处理,是较为理想的处理方案。     

Mechanical and tribological properties of PA66/PPS blend. III. Reinforced with GF

Based on previous work, 70 vol % PA66/30 vol % PPS blend was selected as a matrix, and the PA66/PPS blend reinforced with different content of glass fiber (GF) was prepared in this study. The mechanical properties of PA66/PPS/GF composites were studied, and the tribological behaviors were tested on block‐on‐ring sliding wear tester. The results showed that 20–30 vol % GF greatly increases the mechanical properties of PA66/PPS blend. When GF content is 20 vol %, the friction coefficient of composite is the lowest (0.35), which is decreased by 47% in comparison with the unfilled blend. The wear volume of the GF‐reinforced PA66/PPS blend composite decreases with the increase of GF content. However, the wear‐resistance is not apparently improved by the addition of GF in the experimental range for comparison with unfilled PA66/PPS blend. The worn surface and the transfer film on the counterface were examined by scanning electron microscopy (SEM). The observations revealed that the friction coefficient of composite depends on the formation and development of a transfer film. The wear mechanism involves polymer matrix wear and fiber wear. The former consists of melting wear and plastic deformation of the matrix, while the latter includes fiber sliding wear, cracking, rupturing, and pulverizing. The contributions of the matrix wear and the fiber wear determine the ultimate wear volume of PA66/PPS/GF composite. In addition, the abrasive action caused by the ruptured glass fiber is also a very important factor. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 102: 523–529, 2006