碳纤维的电化学氧化处理研究进展

就碳纤维的电化学氧化处理的研究,分别论述了影响其表面含氧基团含量的几个因素,如电解质的种类、电解质的浓度和氧化处理时间,以及表面处理后的表征方法．并总结了近年来的研究情况．     

碳纤维的电化学氧化表面处理

本文综述了关于碳纤维电化学氧化表面处理的研究现状,碳纤维表面的化学表征,以及处理对碳纤维及其复合材料性能的影响;同时也总结了碳纤维表面处理对于提高碳纤维／树脂复合材料层间剪切强度的解释机理。     

粘胶基碳纤维连续式电化学氧化表面处理（1）：碳纤维表面的物理 …

本文报道了用连续式电化学氧化表面处理粘胶基碳纤维表面,并测定了处理后碳纤维的单丝强度,表面浸润性,表面活性官能团含量及表面形貌等表面物理化学性能。结果表明：粘胶基碳纤维经电化学氧化表面处理可以有效地在表面主生活性官能团和提高表面粗糙度,从而有效地提高表面润湿性,但经处理后单丝强度较易下降,因此需精确控制处理的条件。     

电化学氧化对碳纤维表面性质的影响

用电化学氧化处理了碳纤维,并进行了红外光谱,浸润实验,拔出实验和循环伏安实验测定。结果发现,经过电化学氧化处理,碳纤维的表面接上了丰富的官能团,大量活性碳原子被剥离出来,浸润性质明显改善,拔出强度提高了33%,在溶液中电化学响应明显改善,适合作为电化学分析电极。     

碳纤维表面电化学处理的初步研究

采用NaOH溶液作为电解质,对碳纤维表面进行电化学阳极氧化处理。用化学分析法分析了碳纤维表面含氧官能团浓度的变化,借助于扫描电镜对碳纤维表面形态及SCFRER复合材料的剪切断口形貌进行了考察。     

碳纤维表面电化学氧化的研究

主要采用电化学氧化法对聚丙烯腈(PAN)基碳纤维进行连续氧化处理,利用扫描电子显微镜(SEM)、X射线光电子能谱(XPS)和动态力学热分析(DMTA)对碳纤维表面处理效果进行了研究。SEM表面形貌研究结果表明,碳纤维经电化学氧化处理后,其表面的粗糙度和比表面积增大。XPS表面化学分析表明,经电化学氧化处理后的碳纤维表面羟基含量提高55％,活性碳原子数增加18％。DMTA谱图表明经电化学氧化处理的碳纤维增强树脂基复合材料(CFRP)其玻璃化温度(Tg)提高5℃、损耗角正切(tanδ)较未处理的降低30％。定量计算出的界面黏结参数A和α与CHRP的层间剪切强度(ILSS)所反映的碳纤维与树脂间界面黏结效果是一致的。研究结果表明,采用适当的处理条件可使CFRP的ILSS提高20％以上。     

粘胶基碳纤维连续式电化学氧化表面处理(1)--碳纤维表面的物理化学性能

本文报道了用连续式电化学氧化表面处理粘胶基碳纤维表面,并测定了处理后碳纤维的单丝强度、表面浸润性、表面活性官能团含量及表面形貌等表面物理化学性能.结果表明:粘胶基碳纤维经电化学氧化表面处理可以有效地在表面产生活性官能团和提高表面粗糙度,从而有效地提高表面润湿性,但经处理后单丝强度较易下降,因此需精确控制处理的条件.     

粘胶基碳纤维连续式电化学氧化表面处理：（Ⅱ）碳纤维增强复合材 …

本文用短支梁三点弯曲法及Ｆｒａｇｍｅｎｔ法测定了连续式电氧化处理粘胶基碳纤维与酚醛树脂及环氧树脂复合材料界面粘合性,并用ＳＥＭ观察了其界面的形貌。结果表明：在本试验范围内经电化学中以使粘胶基碳纤维／酚醛树脂复合材料界面的粘合强度提高２５％,而粘胶基碳纤维／环氧树脂复合材料界面的粘合强度可提高１００％。这可能是由于环氧树脂可与碳纤维表面的官能团形成化学键的原因。     

粘胶基碳纤维连续式电化学氧化表面处理(Ⅱ)碳纤维增强复合材料的界面

本文用短支梁三点弯曲法及Fragment法测定了连续式电氧化处理粘胶基碳纤维与酚醛树脂及环氧树脂复合材料界面粘合性 ,并用SEM观察了其界面的形貌。结果表明 :在本试验范围内经电化学氧化处理可以使粘胶基碳纤维 /酚醛树脂复合材料界面的粘合强度提高25 % ,而粘胶基碳纤维 /环氧树脂复合材料界面的粘合强度可提高100 %。这可能是由于环氧树脂可与碳纤维表面的官能团形成化学键的原因。     

碳纤维表面处理技术研究进展

介绍了在碳纤维增强树脂基复合材料中常用的碳纤维表面处理技术,以及不同处理方式对碳纤维力学性能及其增强的聚合物复合材料力学性能的影响。比较了各种表面处理技术的优缺点,并分析了碳纤维表面处理技术的发展趋势。目前,碳纤维的表面处理技术主要有电化学氧化法、偶联剂涂层处理、气相氧化法、液相氧化法和等离子体处理,其中,气相氧化法是目前比较常用的方法,电化学氧化法是目前唯一能够在碳纤维制备时可在线连续运行的技术,且经电化学氧化处理过的碳纤维增强树脂基复合材料的整体性能均得到提高。采用碳纳米管和石墨烯等碳纳米材料对碳纤维进行表面处理已成为新的研究热点,碳纤维表面处理的低成本化、绿色化和连续生产化将是今后的重点研究方向。     

Solid Ceramic Fibers via Impregnation of Activated Carbon Fibers

A process has been developed which allows the preparation of some solid ceramic fibers. In this process, activated carbon fibers which are porous throughout their entire diameter are impregnated with metal-containing solutions such as silicon tetrachloride. Calcination and sintering result in the formation of solid SiO₂ fibers. Use of woven mats or nonwoven felts of activated carbon fibers results in the formation of woven mats or nonwoven felts of silica fibers.     

Characterization of Silver Particles in Silver-Containing Activated Carbon Fibers Prepared from Liquefied Wood

Silver particles in silver-containing activated carbon fibers prepared from liquefied wood were characterized by X-ray diffraction, X-ray photoelectron spectrometer, scanning electron microscope, and nitrogen adsorption isotherms. Silver irons (Ag⁺) and metallic silver (Ag⁰) were detected in fibers, and the amount of Ag⁰ was much higher than that of Ag⁺. Ag⁰ were migrated and aggregated together to form silver particles with a wide size (0–5μm), which were distributed in micropores, mesopores, and surface of fibers. The mean size of silver particles on the surface was directly related to soaking concentration, while the larger silver particles were easier to peel off from the surface. Also, the increasing micropores and mesopores were blocked by silver particles at higher concentration, and some blocked mesopores were converted into micropores. When the washing treatment was carried out, the silver particles on the surface were removed significantly, resulting in an increase in mesopore quantity. However, most of the silver particles in micropores were firmly supported. The silver-containing activated carbon fibers showed the high and lasting antibacterial activity.     

Surface Characterization of Plasma Treated Carbon Fibers and Adhesion to a Thermoplastic Polymer

The surface chemistry of IM7 carbon fibers was characterized by x-ray photoelectron spectroscopy (XPS). The fiber surface energetics were determined from a two-liquid tensiometric method. The adhesion between as-received and plasma-treated carbon fibers and polyethersulfone (PES) was measured by the microbond pull-out test.

The surface characterization techniques showed that the effect of any plasma treatment is attained within less than 15 seconds. It was found that both argon and air plasmas increased the oxidation state of the fiber surface and that they reduced the dispersive component (γ_s ^d) of the fiber surface free energy considerably. The ammonia plasma treatment resulted in a cleaning of the surface. This plasma treatment was also effective in improving the fiber/matrix adhesion of quenched samples. A similar adhesion enhancement between as-received fibers and PES is obtained by annealing the samples above the Tg of the polymer. The air plasma treatment did not have any significant effect on the fiber/matrix adhesion.     

Surface Characterization of Plasma Treated Carbon Fibers and Adhesion to a Thermoplastic Polymer

The surface chemistry of IM7 carbon fibers was characterized by x-ray photoelectron spectroscopy (XPS). The fiber surface energetics were determined from a two-liquid tensiometric method. The adhesion between as-received and plasma-treated carbon fibers and polyethersulfone (PES) was measured by the microbond pull-out test.

The surface characterization techniques showed that the effect of any plasma treatment is attained within less than 15 seconds. It was found that both argon and air plasmas increased the oxidation state of the fiber surface and that they reduced the dispersive component (γ_s^d) of the fiber surface free energy considerably. The ammonia plasma treatment resulted in a cleaning of the surface. This plasma treatment was also effective in improving the fiber/matrix adhesion of quenched samples. A similar adhesion enhancement between as-received fibers and PES is obtained by annealing the samples above the Tg of the polymer. The air plasma treatment did not have any significant effect on the fiber/matrix adhesion.     

聚丙烯腈基碳纤维及其增强复合材料

聚丙烯腈（PAN）基碳纤维作为一种高比强度和高比模量的增强型与功能型高性能纤维材料,在航空航天、国防军工及文体用品等方面都有广泛的应用。文章主要介绍了聚丙烯腈基碳纤维的制备、结构与性能及其在复合材料中的应用。     

活性炭纤维的高功能化

综合评述国内外在活性炭纤维（ACF）的形态改变、结构控制、碳合金化（化学改性）等方面开拓新功能,提高性能／价格比所进行的研究与开发现状。     

Texture and Properties of Acrylonitrile–Ammonium Itaconate Copolymer Precursor Fibers and Carbon Fibers

Acrylonitrile–ammonium itaconate copolymer {P[AN-co-(NH₄)₂IA]} was fabricated by free-radical solution copolymerization of acrylonitrile (AN) and ammonium itaconate [(NH₄)₂IA]. The copolymer was confected into a spinning solution (dope) and spun into precursor fibers. Then the precursor fibers were converted to carbon fibers by stabilization and carbonization processes. Another copolymer of acrylonitrile–itaconic acid [P(AN-co-IA)] and its resultant fibers were studied in contrast. Due to preferable hydrophilicity and facilitating cyclization reaction in stabilization process, P[AN-co-(NH₄)₂IA] fibers could increase the draw-ratio in the spinning process and in the stabilization process to attenuate some property-limiting facts in precursor fibers and carbon fibers. It has been found P[AN-co-(NH₄)₂IA] precursor fibers gave a 30% improvement in tenacity over P(AN-co-IA) precursor fibers. Results for P[AN-co-(NH₄)₂IA] precursor fibers carbonized at 1400°C ultimately showed a 26.7% increase in carbon fiber tensile strength over P(AN-co-IA) based carbon fibers. Characterization analysis using scanning electron microscope (SEM), transmission electron microscope (TEM) and high resolution transmission electron microscope (HRTEM) manifested that these improvements are due to fewer surface defects, better interior morphology, higher degree of orientation and graphitization.     

碳纤维中微孔缺陷的小角X射线散射研究方法

碳纤维的小角X射线散射表明存在沿纤维轴方向取向的针形微孔。应用小角X散射可以得到微孔的尺寸和分布等的信息。文章主要阐述了微孔长度L、取向角Beq,孔隙率P,回转半径Rt,横截面积S等参数的计算方法。     

聚丙烯腈基碳纤维生产工艺特性研究

以丙烯酸 (AA)为第二共聚单体与丙烯腈 (AN)进行溶液聚合 ,偶氮二异丁腈(AIBN)为引发剂 ,二甲基亚砜 (DMSO)作为溶剂合成聚丙烯腈 (PAN)原丝纺丝溶液。研究了单体浓度、引发剂的用量等对聚合反应的影响。探讨了聚丙烯腈原丝及其预氧丝、碳纤维制备的工艺过程 ,对纤维的结构和性能进行了 SEM和 TEM分析     

干喷湿纺法PAN基碳纤维表面处理的研究

以碳酸氢铵为电解质,对干喷湿纺法PAN基碳纤维进行了连续表面处理。通过扫描电子显微镜（SEM）分析其微观结构,同时利用万能材料实验机研究碳纤维及其复合机理。结果表明,随着处理电流密度的增大,碳纤维抗拉强度呈降低趋势。电化学处理碳纤维,电流密度最佳范围应为43．6A·m-^2～54．4A·m^-2,且碳纤维表面官能团对提高复合材料的层间剪切强度起关键作用。