超细碳纤维毡的制备及其形貌研究

采用静电纺丝法制备了聚酰胺酸（PAA）无纺布纤维毡,通过亚胺化工艺得到聚酰亚胺（PI）纤维毡,再以PI纤维毡为前驱体经高温碳化工艺制备PI基超细碳纤维毡,并对制得的PI基超细碳纤维毡进行了扫描电镜（SEM）形貌分析和元素分析。经SEM分析得知,随着碳化温度的升高碳纤维毡中纤维的直径逐渐减小,其分布略变窄,主要分布在200-300nm之间,当碳化温度达到1000℃时,PI基超细碳纤维毡中纤维的碳含量为96.16％。     

聚酰亚胺/滑石粉/碳纤维复合薄膜的界面性能研究

根据碳纤维表面性质和稀土元素独特的物理化学特性,采用稀土溶液(RES)表面改性方法对碳纤维进行表面改性处理,以改善聚酰亚胺/滑石粉/碳纤维(PI/talc/CF)复合材料的界面结合性能,从而有效地提高PI/talc/CF复合材料的力学性能。采用RES改性方法对碳纤维进行表面改性处理,制备出具有不同界面的PI/talc/CF复合材料。以PMDA-ODA型聚酰亚胺为研究对象,在制备的聚酰胺酸中加入不同量的滑石粉和不同RES浓度处理过的碳纤维这两者的混合物,通过5℃/min匀速升温工艺得到聚酰亚胺/滑石粉碳纤维复合薄膜。对制备的复合薄膜进行各种性能测试和结构表征。研究发现,经过RES处理过的碳纤维和滑石粉可以诱导聚酰亚胺分子围绕其结晶,碳纤维和聚酰亚胺之间界面结合良好。RES表面处理提高碳纤维与PI基体之间的界面结合性能,其中RES浓度为0.3wt%的改性处理方法最有效,拉伸强度提高了9.5%。     

聚酰亚胺共混和复合改性的研究进展

综述了聚酰亚胺(PI)与其它高聚物的共混以及与无机物的复合改性研究进展,着重介绍了PI与环氧树脂、聚氨酯、聚四氟乙烯和聚醚醚酮的共混,以及PI与碳纤维、玻璃纤维、石墨、玻璃微珠、凹凸棒土、无机纳米粒子的复合改性的研究情况,并展望了PI共混和复合材料的应用前景和发展趋势.     

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。     

碳纤维增强热塑性树脂基复合材料的研究现状

综述了国内碳纤维增强聚酰胺（PA6）、聚醚砜（PES）、聚碳酸酯（PC）、聚苯硫醚（PPS）、聚醚砜酮（PPESK）,聚醚醚酮（PEEK）、热塑性聚酰亚胺（PI）等热塑性树脂基复合材料研究现状,对比了热固性树脂基复合材料与热塑性树脂基复合材料性能及成型工艺方面的差异,并对碳纤维增强热塑性树脂基复合材料的成型方法,碳纤维...     

碳纤维/聚酰亚胺复合材料的合成及其性能研究

以均苯四羧酸二元酐-4,4’-二氨基二苯醚(PMDA-ODA)型聚酰亚胺为研究对象,加入不同含量和不同长径比的表面处理之后的碳纤维(CF),采用直接法制备聚酰亚胺/碳纤维(PI/CF)复合薄膜。热酰亚胺化时采用的升温工艺条件:以5℃/min的升温速率从室温升至300℃,恒温30 min。通过各种表征手段,对比讨论碳纤维添加量和长径比对复合薄膜的影响。对制备的PI/CF复合薄膜进行偏光、红外、XRD、拉伸测试。实验结果表明:碳纤维的加入可以诱导聚酰亚胺分子结晶;聚酰亚胺薄膜的聚集态结构和性能受碳纤维的添加量,长径比等的影响。随着碳纤维含量的增加复合薄膜的力学性能先随之增强后又减弱。因此,碳纤维含量过多或过少都不利于增强复合薄膜的力学性能及复合薄膜规整结晶结构的形成。碳纤维长径比越大有助于复合薄膜的力学性能的提高;当添加量为3%时所制备的复合薄膜的聚集态结构较为规整,结晶程度较高,拉伸性强度为96.37 MPa,弹性模量为1 949.97 MPa,断裂伸长率为5.914%。     

环氧基POSS处理碳纤维对聚酰亚胺复合材料性能的影响

以均苯四甲酸酐(PMDA)、间苯二胺(m-PDA)为单体制备出高黏度的聚酰胺酸(PAA),然后采用环氧基多面体低聚倍半硅氧烷(POSS)并辅以2-乙基-4-甲基咪唑固化剂对碳纤维(CF)进行表面处理,再将其与已制备的PAA经载玻片涂膜高温固化制得聚酰亚胺/碳纤维(PI/CF)复合材料,通过FIIR、拉曼光谱、XRD、SEM研究了改性碳纤维对PI/CF复合材料性能的影响。研究表明:POSS的接枝改性增加了CF表面的粗糙度和无序程度,固化剂2-乙基-4-甲基咪唑的加入进一步促进了接枝过程,大量POSS接枝并固化于CF表层,使CF表层粗糙度进一步增加,进而改善了CF与PI基体的界面黏合力和相容性。拉曼光谱研究表明,改性前后CF拉曼光谱经分峰拟合得到的具体参数,涂覆改性后CF的R值有所提升,从2.57提升到2.91,以咪唑作为促进剂处理后R值提升至3.18,提升了23.7%。La值从1.71 nm降至1.38 nm。力学性能分析表明,相比接枝前的CF,接枝处理可明显提高PI/CF复合材料的力学性能,添加3%CF并以POSS涂覆处理,拉伸强度和弹性模量分别较改性前提升了11.1%和6.1%,而涂覆POSS并辅以咪唑固化促进剂改性后拉伸强度和弹性模量分别较改性前提升了24.3%和12%,但是断裂伸长率却有所下降。     

碳纳米管含量对聚酰亚胺/碳纤维复合材料性能的影响

以聚酰亚胺(PI)为基体、碳纤维(CF)和碳纳米管(CNTs)为复合增强体,采用热模压工艺制备了不同CNTs含量的PI/CF/CNTs复合材料。采用电子拉力机、动态热机械分析仪和热重分析仪研究了PI/CF/CNTs复合材料的力学性能、动态力学性能和热稳定性。结果表明,与未加CNTs的PI/CF复合材料相比,CNTs含量为PI质量的0.2%时,PI/CF/CNTs复合材料具有最佳的常温力学性能,其中常温拉伸强度提高19.5%,常温弯曲强度提高20.6%,常温层间剪切强度提高14.7%,玻璃化转变温度则由357℃提高到451℃;CNTs含量为PI质量的0.05%时,PI/CF/CNTs复合材料具有最佳的高温力学性能,其中400℃拉伸强度提高15.8%,400℃弯曲强度提高9.6%,400℃层间剪切强度提高12.8%。CNTs的添加对PI/CF/CNTs复合材料的热稳定性几乎没有影响。     

吉林方大江城碳纤维有限公司

<正>碳纤维短切丝短切碳纤维是由碳纤维长丝短切而成,其基本性能主要取决于其原料——碳纤维长丝的性能。由于其表观行态为一定长度的绒须,较长丝而言,短纤维具有分散均匀,喂料方式多样,工艺简单的优点,在模塑前易于混合得到均一的预混物。可以适用于热塑性和热固性树脂的各类浸润剂,也可适用于各种性能的碳纤维增强塑料颗粒及产品,如增强改性塑料:尼龙(PA)、聚丙烯(PP)、聚碳酸酯(PC)、酚醛(PF)、聚四氟乙烯(PTF E)、聚酰亚胺(PI)等。主要应用于军工、航空航天等高科技领     

碳纤维增强聚醚醚酮的非等温结晶行为与力学性能

利用聚酰亚胺(PI)作为碳纤维(CF)界面改性剂,制备了界面改性碳纤维增强聚醚醚酮(MCF/PEEK)复合材料。采用差示扫描量热仪(DSC)讨论了CF及其界面改性对PEEK非等温结晶行为的影响机制与作用规律,并基于莫志深法研究了MCF/PEEK的非等温结晶动力学;借助DSC和小角X射线散射仪(SAXS)表征不同降温速率下PEEK基体的结晶结构,采用万能试验机评价了MCF/PEEK的力学性能。结果发现:CF对PEEK的结晶有较为明显的异相成核促进作用,经过PI界面改性之后成核作用有所下降,但结晶行为仍较纯PEEK更容易发生,整体结晶速率更快;随冷却速率的增大,基体结晶度、片晶厚度与长周期均减小,MCF/PEEK的拉伸强度与模量也显著减小,层间断裂韧性提高。     

Evaluation of tribological performance of surface‐treated carbon fiber‐reinforced thermoplastic polyimide composite

The effect of surface treatment [rare earth solution (RES) and air oxidation] of carbon fibers (CFs) on the mechanical and tribological properties of carbon fiber‐reinforced polyimide (CF/PI) composites was comparatively investigated. Experimental results revealed that surface treatment can effectively improve the interfacial adhesion between carbon fiber and PI matrix. Thus, the flexural strength and wear resistance were significantly improved. The RES surface treatment is superior to air oxidation treatment in promoting interfacial adhesion between carbon fiber and PI matrix. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci 2008     

The effect of carbon fiber content on the friction and wear properties of carbon fiber reinforced polyimide composites

The current study examines the tribological performance of polyimide and carbon fiber reinforced polyimide (CF/PI) under dry sliding condition. Different contents of carbon fibers were employed as reinforcement. All filled and unfilled polyimide composites were tested against CGr15 ball and representative testing was performed. The effects of carbon fiber content on tribological properties of the composites were investigated. The worn surface morphologies of neat PI and its composites were examined by scanning electron microscopy and the wear mechanisms were discussed. Moreover, all filled polyimides have superior tribological characteristics to unfilled polyimides. The optimum wear reduction was obtained when the content of carbon fiber is 20 vol %. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci, 2008     

纳米芳纶增强聚酰亚胺气凝胶纤维的制备及其性能研究

以3,3′,4,4′-联苯四甲酸二酐和1,4-二氨基苯二胺共聚制备聚酰胺酸盐前驱体溶液,通过湿法纺丝,然后经过超临界二氧化碳干燥和热亚胺化处理制得纳米芳纶(ANFs)增强聚酰亚胺(PI)气凝胶纤维(简称PI/ANFs气凝胶纤维),研究了气凝胶纤维的结构与性能。结果表明:傅里叶变换红外光谱和X射线衍射光谱表征所制备的PI/ANFs气凝胶纤维为目标产物;PI/ANFs气凝胶纤维的截面具有大量的孔结构且分布较为均匀;PI/ANFs气凝胶纤维的比表面积为152 m²/g,孔径主要分布在10~25 nm之间,密度为0.21 g/cm³,孔隙率大于85%;PI/ANFs气凝胶纤维在空气气氛下的最大热分解温度为625℃,在氮气气氛下950℃的残炭率为67%;PI/ANFs气凝胶纤维的断裂强度和初始模量分别为(2.5±0.5)MPa和(109±10)MPa。     

Fiber hybrid polyimide‐based composites reinforced with carbon fiber and poly‐p‐phenylene benzobisthiazole fiber: Tribological behaviors under sea water lubrication

Fiber hybrid polyimide‐based (PI‐based) composites reinforced with carbon fiber (CF) and poly‐p‐phenylene benzobisthiazole (PBO) fiber of different volume fractions were fabricated by means of hot press molding technique, and their mechanical properties and tribological behaviors under sea water lubrication were systematically investigated in relation to the synergism of CF and PBO fiber. Results showed that the incorporation of CF or PBO fiber improved the tensile strength, hardness, and wear resistance of PI. More importantly, because of the synergistic enhancement effect between CF and PBO fiber on PI matrix, the combination of 10%CF and 5%PBO fiber reinforced PI‐based composite had the best mechanical and tribological properties, showing promising application in ocean environment. POLYM. COMPOS., 37:1650–1658, 2016. © 2014 Society of Plastics Engineers     

非织造和产业用高性能纤维

介绍了碳纤维、芳纶、聚对苯撑苯并双噁唑(PBO)纤维、超高相对分子质量聚乙烯(UHMWPE)纤维、聚苯硫醚(PPS)纤维、聚酰亚胺(P)I纤维、玄武岩纤维、芳砜纶的国内外发展概况及其在产业领域的应用。     

Preparation and properties of T300 carbon fiber‐reinforced thermoplastic polyimide composites

In this study, a series of T300 carbon fiber‐reinforced polyimide (CFRPI) composites were prepared by laminating premolding polyimide (PI) films with unidirectional carbon fiber (CF) layers. On the basis of PI systems design, the effect of CF volume fraction, processing conditions, and PI molecular structure on the properties of CFRPI composites was studied in detail. In addition, two kinds of nano‐particles, including carbon nano‐tube (CNT) and SiO₂ were filled into the premolding PI films with different concentrations. And the effect of nano‐particles on the properties of CFRPI composites was also investigated. The surface characteristic of T300 CF was measured by X‐ray photoelectron spectroscopy (XPS) and Fourier transform infrared spectroscopy (FTIR). The properties of premolding PI film and CFRPI composites were measured by dynamic mechanical analysis (DMTA), SANS testing machine, scanning electron microscopy (SEM), and so forth. These experimental results showed that the properties of CFRPI composites were mainly affected by the premolding PI film and molding condition. The change of CF volume fraction from 55% to 65% took little effect on the mechanical properties of CFRPI composites. In addition, the incorporation of nano‐particle SiO₂ could further improve the properties of CFRPI composites, but CNT hardly improved the properties of CFRPI composites. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 102: 646–654, 2006     

Joule heat dependence of dynamic tensile modulus of polyimide-vapor grown carbon fiber nanocomposites under applied electric field evaluated in terms of thermal fluctuation-induced tunneling effect

To study mechanical and structural stabilities of polyimide (PI) and carbon filler composites by Joule heat, PI-vapor grown carbon fiber (VGCF) composites were fabricated by in situ polymerization to realize excellent dispersion of VGCFs in PI matrix. Adoption of VGCFs similar to rigid carbon fibers is the strategy to investigate the conductive mechanism theoretically in terms of thermal fluctuation-induced tunneling conduction. Dynamic tensile modulus and X-ray intensity under applied electric field were measured to investigate frequency-temperature dependence of the modulus by Joule heat in relation to the electron transfer mechanisms. Such simultaneous measurements for the mechanical and structural properties under electric field provided important information about the characteristic of polymer-filler composites. As the results, good heat resistance of PI-VGCF composites was clarified to be attributed to very few thermal fluctuation of PI chain arrangement in spite of collision between electrons flowed out from the VGCF gaps and atoms of PI chains.     

巡视国外高科技纤维动向

到2010年国外的PAN基碳纤维预期将以13%的年增长率增长,而对位芳酰胺纤维则将以9%增长,吴羽和三菱化学的沥青基碳纤维产能,2007年将各扩大至1100t/a和1000t/a。聚酰亚胺中空纤维气体分离膜将于2007年实现产能翻番,东丽的聚乳酸纤维2007年将由目前的250t/a扩大至600t/a,昭和电工的纳米碳纤维产能也将于2007年初扩大2.5倍,由目前的40t/a扩大至100t/a。在新品种方面,聚酮纤维将于2008年建成生产厂,主要用于高级轮胎帘子线;三菱人造丝则首创湿纺芯鞘型纤维,用作调温及导电、发热等纤维。在应用方面,各公司开发了各种新市场。