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。     

Resistance welding of carbon fibre reinforced polyetheretherketone composites using metal mesh and PEI film

Weldability of polyetheretherketone( PEEK) with polyetherimide( PEI) is tested. And carbon fiber reinforced PEEK laminates are resistance welded using stainless steel mesh heating element. The effects of the welding time and welding pressure on the lap shear strength of joints are investigated. Results show that PEEK can heal with PEI well in welding condition and the lap shear strength of PEEK/CF(carbon fibre) joint increases linearly with welding time, but reaches a maximum value when welding pressure ranging from 0.3 MPa to 0.5 MPa with constant welding time. The fracture characteristics of surface are analyzed by SEM techniques, and four types of fracture modes of lap shear joints are suggested.     

连续CF增强PEEK复合材料层压板的制备工艺

采用熔融浸渍法制备了连续碳纤维(CF)增强聚醚醚酮(PEEK)复合材料预浸带,并层压成型制备复合材料层压板。研究了成型温度、成型压力、成型时间、纤维含量等因素对复合材料层压板力学性能的影响。结果表明,在成型温度为370℃、成型压力为12 MPa、成型时间为70 min、纤维含量为61%的工艺条件下,连续CF增强PEEK复合材料层压板的力学性能达到最优值,弯曲强度和弯曲弹性模量分别达到(1 750.76±49.13)MPa和(107.54±6.35)GPa,层间剪切强度达到(100.04±6.88)MPa,缺口冲击强度为(84.44±1.54)k J/m2。随着冷却速率的增大,复合材料层压板的弯曲性能和层间剪切强度下降,而缺口冲击强度提高。SEM分析表明,复合材料层压板的界面粘结良好。     

芳杂环聚合物质子交换膜的制备

引言直接甲醇燃料电池(direct methanol fuel cell,DMFC)由于无需将甲醇转变为氢气,直接使用液体燃料甲醇,与氢氧燃料电池相比,省去许多辅助设备,体积小,成为了便携式电源的最佳候选者,特别适合用于可移动电源,如移动电话、笔记本电脑和照相机等。质子交换膜是直接甲醇燃料电池的核心组成之一,其性能好坏直接影响电池的性能和     

聚醚醚酮及其改性的人工关节材料的摩擦磨损性能研究进展

聚醚醚酮(Polyetheretherketone,PEEK)优异的耐磨损性能为研发新一代高寿命人工关节提供了新希望。分别综述了采用常规摩擦学方法对纯PEEK、碳纤维增强PEEK、颗粒填充PEEK、等离子改性PEEK等作为人工关节材料,和采用模拟试验机方法对PEEK在人工髋关节、人工膝关节等假体关节面发挥耐磨损性能的应用和研究进展,最后展望了PEEK及其改性的人工关节材料摩擦磨损性能研究的发展趋势。     

纳米SiC和微米SiC填充聚醚醚酮的磨损机理研究

利用热压法分别以纳米ＳｉＣ和微米ＳｉＣ作为填产制取了两类不同ＳｉＣ填充的聚醚醚酮复合材料，并对它们在干摩擦条件下的摩擦磨损性能进行了研究，同时还用扫描电子显微镜对摩擦表面形貌进行了观察，进而对材料的磨损机理作了分析与讨论。研究结果表明，１０％（ｗｔ）纳米ＳｉＣ作为填料能有效的改善其填充聚醚醚酮的摩擦磨损性能，而相同含量的微米ＳｉＣ作为填为只能使其填充聚醚醚酮的耐磨性能有所改善，但没有减摩效果。微米     

Effect of nanometer SiC filler on the tribological behavior of PEEK under distilled water lubrication

The composites of polyetheretherketone (PEEK) filled with nanometer SiC of different proportions were prepared by compression molding. The tribological behaviors of the composites under lubrication of distilled water were investigated and compared with that under dry sliding, on an M‐200 friction and wear test rig, by running a plain carbon steel (AISI 1045 steel) ring against the composite block. The worn surfaces of nanometer SiC filled‐PEEK and the transfer film were observed by means of scanning electron microscopy (SEM) and electron probe microanalysis (EPMA). As the results, nanometer SiC as the filler greatly improves the wear resistance of PEEK under dry sliding and distilled water lubrication, though the composites show different dependence of wear resistance on the filler content. Nanometer SiC‐filled PEEK showed signs of slight scuffing under distilled water lubrication, while a thin, uniform, and tenacious transfer film was formed on the surface of the counterpart steel ring. On the contrary, unfilled PEEK under lubrication of water showed signs of severe plowing and erosion, while the worn surface of the counterpart ring was very rough, and a discontinuous PEEK transfer film was formed. Thus, the different friction and wear behaviors of unfilled PEEK and nanometer SiC‐filled PEEK can be attributed to the different characteristics of the corresponding transfer films. © 2000 John Wiley & Sons, Inc. J Appl Polym Sci 78: 609–614, 2000     

The friction and wear properties of nanometer ZrO2-filled polyetheretherketone

Nanometer ZrO₂ filled polyetheretherketone (PEEK) composite blocks with different filler proportions were prepared by compression molding. Their friction and wear properties were investigated on a block-on-ring machine by running a plain carbon steel (AISI 1045 steel) ring against the composite block. The morphologies of the wear traces were observed by scanning electron microscopy (SEM). Results indicated that nanometer ZrO₂-filled PEEK exhibited lower friction coefficient and wear rate in comparison with pure PEEK. The lowest wear rate was obtained with the composite containing 7.5 wt % ZrO₂. The SEM pictures of the wear traces indicated that the plucked and ploughed marks appeared on the wear scar of pure PEEK, while the scuffing on the wear scar of 7.5 wt % nanometer ZrO₂-filled PEEK was obviously abated. Thus, it was inferred that the improvement in the tribological behavior of nanometer ZrO₂-filled PEEK composite was closely related to the improved characteristics of the worn surfaces. © 1998 John Wiley & Sons, Inc. J Appl Polym Sci 69: 135–141, 1998     

Sulfonation of polyetheretherketone by chlorosulfuric acid

Sulfonated poly(oxa-p-phenylene-3,3-phthalido-p-phenylene-oxa-p-phenylene-oxy-phenylene) (PEEK-WC) with various degrees of substitution was obtained by reaction of polyetheretherketone with neat chlorosulfuric acid. Highly sulfonated PEEK-WC was freely soluble in cold water. By working under suitable reaction conditions, no degradation of the polymeric chain was detected. The modified PEEK-WC was able to form asymmetric membranes. The expected chlorosulfonated derivatives were never achieved. © 1998 John Wiley & Sons, Inc. J. Appl. Polym. Sci. 70: 477–482, 1998