碳纳米管化学镀镍及其对聚合物纤维的抗静电能力的提高

使聚合物与抗静电剂混纺形成“海岛”型内部结构，基于其通过基团吸湿放电而消除静电的抗静电原理，以碳纳米管混纺有机抗静电剂应用于聚合物纤维。碳纳米管强化抗静电载体周围的电场，促进了基团吸湿层内的电荷耗散过程。通过摩擦静电荷的测试结果显示：碳纳米管的加入显著地提高了聚合物纤维的抗静电能力。经过化学沉积金属镍处理的碳纳米管，抗静电效果进一步显著。     

碳纳米管对三种有机抗静电剂性能的改进

通过碳纳米管来改进有机抗静电剂的性能,用于聚合物抗静电纤维.碳纳米管分散在有机抗静电剂载体PR86,TS40和TS51中制成复合抗静电剂CNTs/PR86,CNTs/TS40和CNTs/TS51,与聚丙稀(PP)混纺制备CNTs/PR86/PP纤维,CNTs/TS40/PP纤维和CNTs/TS51/PP纤维.通过对摩擦静电荷的测试结果表明,含碳纳米管的有机抗静电剂相对于纯有机抗静电剂更进一步提高了丙纶纤维的抗静电能力.     

含碳纳米管的新型抗静电纤维的制备和性能

将多壁碳纳米管分散在自制的抗静电载体PR-86中制备出新型、高效和耐久的抗静电母粒．抗静电母粒的添加量仅为0．5％就可以制备出性能优良的“基体-微纤”型抗静电PP纤维．该纤维的抗静电机理为异极性大分子放电机理．多壁碳纳米管的存在增强了微纤相的极化程度和抗静电母粒的抗静电效果．抗静电纤维的抗静电性具有耐久性．抗静电母粒对纤维的性能基本上没有影响．     

碳纳米管/聚合物基纤维材料的研究进展

简要介绍了碳纳米管在聚合物材料中的研究进展，重点介绍了碳纳米管/聚合物基纤维材料及其性能的研究，提出添加碳纳米管不仅可以有效提高纤维材料的力学性能，而且可以改善其抗静电性能。同时对碳纳米管在纤维中的取向及由此导致的对材料性能的影响进行了论述。     

碳纳米管增强PA6纤维的性能

将碳纳米管(CNT)在分散剂或分散剂和聚合物(PA6)载体中处理后制备出两种母粒,将其作为增强材料分别和PA6切片熔融共混纺丝,制备出碳纳米管的增强PA6纤维,研究其结构和力学性能.CNT含量低于0.5%(质量分数)时,使用两种母粒制备出的纤维强度和模量都提高,NT含量为0.03%时增强的效果最好.由碳纳米管和分散剂组成的母粒增强效果更好,NT的含量为0.03%时就能使PA6纤维的强度和模量分别提高23%和76%.这种增强纤维是一种微纤增强纤维,纳米CNT在纤维中均匀分散且沿着纤维轴的方向取向.这种结构能有效地转移载荷,具有增强作用,且取向性越好,增强效果越好.     

碳纳米管及碳纳米管纤维的性能与应用

碳纳米管是由单层或多层石墨片卷曲而成的无缝纳米级管状壳层结构。扼要介绍了碳纳米管、碳纳米管纤维的合成方法及近几年来国内外制备的各种碳纳米管产品。碳纳米管、碳纳米管纤维由于其优良的力学、电学特性可以制成气体吸附体、生物模板、传动装置、增强复合体、催化剂载体、探测器、传感器、纳米反应器等产品，在航空、能源、医药、化学等技术领域广泛应用。     

碳纳米管及碳纳米管纤维的性能与应用

碳纳米管是由单层或多层石墨片卷曲而成的无缝纳米级管状壳层结构.扼要介绍了碳纳米管、碳纳米管纤维的合成方法及近几年来国内外制备的各种碳纳米管产品.碳纳米管、碳纳米管纤维由于其优良的力学、电学特性可以制成气体吸附体、生物模板、传动装置、增强复合体、催化剂载体、探测器、传感器、纳米反应器等产品,在航空、能源、医药、化学等技术领域广泛应用.     

复合同轴生物碳纳米管纤维制备方法

利用同轴静电纺丝方法制备碳纳米管/生物聚合物的"壳-芯"结构纤维,实验发现碳纳米管加入(质量分数)0.01%能很好与聚合物融为一体,纺出内外层均可以复合碳纳米管的复合纤维,外层直径最大4000 nm、内层为2000 nm,而最小外直径165 nm,外层壁厚为127 nm,控制方法比单轴静电纺丝复杂,电压提高有利于纤维直径减小,可达到几微米,但纺丝速率达到最大值有一个最佳电压范围,碳纳米管加入提高了纤维的热稳定性,拉伸提高纤维的结晶度。     

纤维/混杂纤维-矿渣地质聚合物复合材料的弯曲强度与弯曲韧性

碱激发矿渣地质聚合物存在脆性大、韧性差、易开裂等缺陷。利用纤维/混杂纤维对矿渣地质聚合物进行改性,以纤维-矿渣地质聚合物复合材料的弯曲强度与弯曲韧性作为考察指标,分析了3种单一纤维及2种混杂纤维对矿渣地质聚合物的增强与增韧效果。研究结果表明,碳纤维增强效果优于钢纤维、玄武岩纤维,钢纤维增韧效果优于碳纤维、玄武岩纤维,而玄武岩纤维增强及增韧效果相对较差;碳纤维与钢纤维混杂,可充分发挥碳纤维的增强效应和钢纤维的增韧效应,适当掺量下混杂纤维较单一纤维具有更好的增强与增韧效果;纤维与浆料的容重差对矿渣地质聚合物硬化体的均质性具有重要影响,碳纤维与钢纤维混杂可显著降低不同加载方向下矿渣地质聚合物弯曲强度与弯曲韧性的离散性。     

新型抗静电PET纤维的耐久、耐干燥特性的研究

通过含金属盐的脂肪酸聚乙二醇酯（PM）与BHET的共缩聚反应,制备了大分子主链上含有金属盐的聚醚酯抗静电剂（PEEM）,PEEM与常规PET切片共混纺丝制备的涤纶纤维具有优良的抗静电性能,且其抗静电性,耐洗涤性均优于添加不含金属盐的聚醚酯抗静电剂（PEE）的涤纶纤维,经沸水处理后仍能达到理想的静电效果,此种抗静电纤维在极端干燥（RH≤30％）条件下仍能具备优良的抗静电性能。最后采用红外,光学显微镜等测试方法研究了纤维结构。     

碳纳米管的镍铜复合金属镀层及其抗电磁波性能

利用酸处理技术对CNT进行了改性处理。应用化学镀层法对改性后的CNT镀镍、铜及镍铜混合镀层技术进行了一系列研究。通过TG、XRD、SEM等分析表明,通过控制镀层处理的工艺条件,可以在CNT表面均匀原位生长出金属镀层,在一定条件下可形成纳米级稳定结构组成的镀层金属,而不同的金属材料形成的金相结构和分布状态有所不同。对镀层的碳纳米管材料采用四电极法和波导管法进行导电与电磁屏蔽性能测试,分析证明,复合金属镀层的电导率为17.3S/cm,电磁波屏蔽率为71dB,达到了目前国内外同类材料应用性能的优异水平。      

碳纳米管的特性及其高性能的复合材料

碳纳米管具有超强的力学性能、极高的纵横比和独特的导电特性,是制备复合材料的理想形式。评述了目前碳纳米管复合材料的制备及其应用研究的动态。用化学镀方法制备的镍基碳纳米管复合镀层比传统的复合镀层具有更高的耐磨性能,结构为非晶态。讨论了复合镀制备金属基碳纳米管复合镀层的优越性及应用。用原位聚合法合成了导电聚苯胺-碳纳米管的复合材料,可以作为电池和电化学超级电容器的电极材料。      

Alignment of carbon nanotubes and reinforcing effects in nylon-6 polymer composite fibers

Alignment of pristine carbon nanotubes (P-CNTs) and fluorinated carbon nanotubes (F-CNTs) in nylon-6 polymer composite fibers (PCFs) has been achieved using a single-screw extrusion method. CNTs have been used as filler reinforcements to enhance the mechanical and thermal properties of nylon-6 composite fibers. The composites were fabricated by dry mixing nylon-6 polymer powder with the CNTs as the first step, then followed by the melt extrusion process of fiber materials in a single-screw extruder. The extruded fibers were stretched to their maxima and stabilized using a godet set-up. Finally, fibers were wound on a Wayne filament winder machine and tested for their tensile and thermal properties. The tests have shown a remarkable change in mechanical and thermal properties of nylon-6 polymer fibers with the addition of 0.5?wt% F-CNTs and 1.0?wt% of P-CNTs. To draw a comparison between the improvements achieved, the same process has been repeated with neat nylon-6 polymer. As a result, tensile strength has been increased by 230% for PCFs made with 0.5% F-CNTs and 1% P-CNTs as additives. These fibers have been further characterized by DSC, Raman spectroscopy and SEM which confirm the alignment of CNTs and interfacial bonding to nylon-6 polymer matrix.     

施镀时间和浓度对碳纳米管镀Ni层厚度的影响

为降低碳纳米管的表面活化能, 改善碳纳米管与金属基体的相容性, 采用化学镀的方法, 在碳纳米管表面镀覆一层金属Ni。研究了施镀时间和镀液浓度对碳纳米管表面镀Ni层厚度的影响。结果表明: 随着施镀时间延长, Ni沉积颗粒变大导致镀Ni层变厚; 镀液浓度增加, 碳纳米管表面沉积的Ni颗粒增多, 镀Ni层逐渐致密。本实验工艺条件下, 镀液浓度为0.08 mol/L, 反应时间为30 min时, 可以在碳纳米管表面镀覆一层界面结合良好且致密的Ni层, 其厚度约为10 nm。热处理能有效缓解镀Ni层应力, 改善界面结合。     

Silver-plated carbon nanotubes for silver/conducting polymer composites

Carbon nanotubes (CNTs) have advantages as conductive fillers due to their large aspect ratio and excellent conductivity. In this study, a novel silver/conducting polymer composite was developed by the incorporation of silver-plated CNTs. It is important to achieve a homogeneous dispersion of nanotubes and to improve the interfacial bonding to utilize the excellent properties of reinforcements in the matrix material. The homogeneous dispersion of nanotubes was achieved by an acid treatment process, and the interfacial contact was improved by electroless silver plating around nanotubes. The resistivity of the silver/conducting polymer composite was decreased by 83% by the addition of silver-plated single-walled carbon nanotubes. Conductive bumps were also screen-printed to demonstrate the capability of the composite as electrical interconnects for multi-layer printed circuit boards.     

Porous Electrospun Fibers with Self‐Sealing Functionality: An Enabling Strategy for Trapping Biomacromolecules

Stimuli‐responsive porous polymer materials have promising biomedical application due to their ability to trap and release biomacromolecules. In this work, a class of highly porous electrospun fibers is designed using polylactide as the polymer matrix and poly(ethylene oxide) as a porogen. Carbon nanotubes (CNTs) with different concentrations are further impregnated onto the fibers to achieve self‐sealing functionality induced by photothermal conversion upon light irradiation. The fibers with 0.4 mg mL^?1 of CNTs exhibit the optimum encapsulation efficiency of model biomacromolecules such as dextran, bovine serum albumin, and nucleic acids, although their photothermal conversion ability is slightly lower than the fibers with 0.8 mg mL^?1 of CNTs. Interestingly, reversible reopening of the surface pores is accomplished with the degradation of PLA, affording a further possibility for sustained release of biomacromolecules after encapsulation. Effects of CNT loading on fiber morphology, structure, thermal/mechanical properties, degradation, and cell viability are also investigated. This novel class of porous electrospun fibers with self‐sealing capability has great potential to serve as an enabling strategy for trapping/release of biomacromolecules with promising applications in, for example, preventing inflammatory diseases by scavenging cytokines from interstitial body fluids.     

Hybrid carbon nanotube–carbon fiber composites with improved in-plane mechanical properties

In this study carbon nanotubes (CNTs) were grown on carbon fibers to enhance the in-plane and out-of-plane properties of fiber reinforced polymer composites (FRPs). A relatively low temperature synthesis technique was utilized to directly grow CNTs over the carbon fibers. Several composites based on carbon fibers with different surface treatments (e.g. growing CNTs with different lengths and distribution patterns and coating the fibers with a thermal barrier coating (TBC) layer) were fabricated and characterized via on- and off-axis tensile tests. The on-axis tensile strength and ductility of the hybrid FRPs were improved by 11% and 35%, respectively, due to the presence of the TBC and the surface grown CNTs. This configuration also exhibited 16% improvement on the off-axis stiffness. Results suggest that certain CNT growth patterns and lengths are more pertinent than the other surface treatments to achieve superior mechanical properties.     

Carbon and glass hierarchical fibers: Influence of carbon nanotubes on tensile,flexural and impact properties of short fiber reinforced composites

Dense carbon nanotubes (CNTs) were grown uniformly on the surface of carbon fibers and glass fibers to create hierarchical fibers by use of floating catalyst chemical vapor deposition. Morphologies of the CNTs were investigated using scanning electronic microscope (SEM) and transmission electron microscope (TEM). Larger diameter dimension and distinct growing mechanism of nanotubes on glass fiber were revealed. Short carbon and glass fiber reinforced polypropylene composites were fabricated using the hierarchical fibers and compared with composites made using neat fibers. Tensile, flexural and impact properties of the composites were measured, which showed evident enhancement in all mechanical properties compared to neat short fiber composites. SEM micrographs of composite fracture surface demonstrated improved adhesion between CNT-coated fiber and the matrix. The enhanced mechanical properties of short fiber composites was attributed to the synergistic effects of CNTs in improving fiber–matrix interfacial properties as well as the CNTs acting as supplemental reinforcement in short fiber-composites.     

Conductivity in carbon nanotube polymer composites: A comparison between model and experiment

Carbon nanotubes (CNTs) demonstrate remarkable conductive behaviour, which suggests promising applications. Their outstanding properties have been used in the development of CNT–polymer composites as possible alternative materials for various applications, such as flexible electrodes, antistatic coatings and piezoresistive sensors. In our study we focused our attention on the evaluation and modelling of CNT-filled epoxy resin electrical conductivity. We discuss the results with regard to the influence of CNTs dimensions and content. Exploiting the Dijkstra algorithm, we implemented a simulation code which determines the shortest route between electrodes in the polymer. The longer the path inside the polymer, the more non-conductive the composite becomes, since polymer resistivity is orders of magnitude higher than that of CNTs. We compared these simulated results with experimental data obtained at several wt% and found a good correspondence between modelling and experimental results.