The main purpose of this thesis is to find out an effective way to solve the dispersion of carbon nanootubes (CNTs) in the polymer matrices with polar groups by means of functionalizing CNTs according to the chain structure and polar groups of the matrix we used in the investigation.CNTs were modified by means of acidification and grafting maleic anhydride in our research. The characterization of functionalized CNTs by Fourier transform infrared spectrum (FTIR), transmission electron microscope (TEM) and scanning electron microscope (SEM) showed that acidification provided CNTs a shorter length and active reaction with maleic anhydride which caused by the introduction of hydroxyl and carboxyl groups to CNTs; and maleic anhydride was successfully grafted to CNTs (the final productions were designated by f-MWCNTs, f-SWCNTs in this thesis). The comparison of the dissolve abilities between modified and pristine CNTs suggested that, once the maleic anhydride was introduced onto the surfaces of MWCNTs, the dissolve ability of MWCNTs in xylene solution was improved greatly compared to pristine CNTs, moreover the dispersion of f-MWCNTs in polyethylene terephthalate was uniform since the interfacial interaction between f-MWCNTs and PET was reinforced and the miscibility of the two components of the nanocomposite was improved greatly due to the hydrogen bond effect between PET chains and f-MWCNTs.f-MWCNTs were melting compounded with poly(ethyleneterephthalate) (PET) by using a twin-screw extruder to prepare PET/MWCNTs nanocomposites. The SEM results showed that the dispersion of f-MWCNTs was fine and the interfacial interaction between f-MWCNTs and PET was strong. The effects of f-MWCNTs on the crystallization behavior of PET nanocomposites were also studied via DSC and POM. The results showed that the nucleation effect of f-MWCNTs in PET crystallization was strong. The nonisothermal crystallization kinetics of PET with f-MWCNTs was analyzed by Jeziorny and Mo methods and the results also proved that the f-MWCNTs clearly accelerated the crystallization process of PET.In order to further study the effect of f-SWCNTs on the microstructure of polymer and explain how interaction between matrix and nanofillers works on the microstructure of composite , PP/OMM、PP/OMMT/f-SWCNTs composites were prepared and investigated. The effects of f-SWCNTs on the microstructure of PP/OMMT nano-composites were investigated by WAXD, SEM, PLM and DSC. Compared with the PP-MA/OMMT binary nanocomposite, in which OMMT was mainly exfoliated, the intercalated OMMT was mainly observed in PP-MA/OMMT/f-SWCNTs ternary nanocomposite due to the stronger interfacial interaction between PP-MA and f-SWCNT prevents more PP-g-MA enter into the interlayer of OMMT gallery during the melt process or during the cooling process the stronger interfacial interaction between PP-MA and f-SWCNTs induces the PP-MA chain segments intercalated into the interlayer of OMMT move out from the gallery, and in this condition only few PP-g-MA chain segments maintain in the interlayer, thus OMMT is mainly intercalated. The results of DSC and PLM show that the f-SWCNTs have great effect on the microstructure of PP-MA/OMMT/f-SWCNTs nanocomposite.PP/PET/f-MWCNTs in-situ microfibrillar composites were also prepared and the dispersion state of f-MWCNTs in composites was investigated by DSC and SEM. The results suggested that f-MWCNTs were mainly located in PET micro-fibrils, leading the viscosity of PET changed, which weakened the microfibrillar ability of PET. Therefore, some PET particles exsisted rather than microfiber in PP/PET/f-MWCNTs composites. Moreover the aspect ration of PET disperse phase would decrease with the increase of f-MWCNTs content.

Hyperbranched poly(amidoamine) was in situ “grafted from” Multi-Walled Carbon Nanotube (MWCNT) surfaces having amino groups (initiator sites) which were prepared via reaction between toluene 2, 4-diisocyanate and carboxylated carbon nanotubes followed by addition of ethylenediamine. Hyperbranched poly(amidoamine) (PAMAM) was propagated from the carbon nanotube surfaces by successive repetition of (1) Michael addition of methyl acrylate to surface amin0o groups and (2) amidation of the resulting esters with ethylenediamine. FT-IR, Raman spectroscopy, UV-Vis, TGA and FE-SEM confirmed the reactions and their products. Using at least one generation of PAMAM, the modified MWNTs were stable for long periods (i.e. more than 1 month) in water. Epoxy/multi-walled carbon nanotubes (MWNTs) composite fibers (about 50μm diameter) were prepared using coagulation spinning in aqueous media. Optical microscopy confirmed the good dispersion of PAMAM modified MWNTs compared to the pristine MWNTs in EP. The PAMAM modified MWNTs also conferred high toughness and good matrix adhesion to the resulting fibers. Flow-induced alignment leads to a preferential orientation of the carbon nanotubes. The mechanical and thermodynamic propreties are also improved by the addition of functional MWNTs.

In this paper, carbon nanotubes were immobilizated on the surface of gold electrode oriently. The surface was then modificated by conductive polymer further and finally came into a rough hairlike one with one-dimension nanowire structure.Single-walled carbon nanotubes (SWNTs) were used in this research, different parameters(time, temperature, treatment methods, etc.) were discussed, so as to determine their effects on purification, cutting and debundling of SWNTs and choose the optimal experimental conditions(mixed concentrated acid, low temperature and ultrasonication) to prepare a stable suspension in a short time. Sodium dodecylbenzene sulfonate (SDBS) was added to enhance the stabilization of the aqueous suspension. A surface condensation reaction between amino and carboxylic groups was then performed by immersing an amino self-assembled monolayer (SAM)-modified gold eletrode into the aqueous suspension of SWNTs with the aid of N-(3-Dimethylaminopropyl)-N’-ethylcarbodiimide hydrochloride (EDC.HC1) and sulfo-N-hydroxysuccinimide (s-NHS), thereafter SWNTs has been immobilized on gold oriently. Poly(3,4-ethylenedioxythiophene) (PEDOT) films were prepared on the SWNT-immoblized electrode by potentiostatic electropolymerization from EDOT aqueous solution, with p-toluene sulfonic acid sodium salt (TsONa) as the supporting electrolytes.Field Emission-scanning electron microscopy (FSEM), transmission electron microscopy (TEM), infrared spectrometry and raman spectrometry were used to characterize the structure and modality of SWNTs before and after acid treatment. Raman spectrometry could also testify the immobilization of SWNTs on gold while atomic force microscopy (AFM) showed the perpendicular standing state of SWNTs on gold surface. Scanning electron microscopy (SEM) was used for observing the rough surface after polymerization of EDOT on modified gold andthe results of cyclic voltammetry (CV) showed that all the modified electrodeshave remarkable improvements in electrochemistry properties.

In this paper, carbon nanotubes were immobilizated on the surface of gold electrode oriently. The surface was then modificated by conductive polymer further and finally came into a rough hairlike one with one-dimension nanowire structure.Single-walled carbon nanotubes (SWNTs) were used in this research, different parameters(time, temperature, treatment methods, etc.) were discussed, so as to determine their effects on purification, cutting and debundling of SWNTs and choose the optimal experimental conditions(mixed concentrated acid, low temperature and ultrasonication) to prepare a stable suspension in a short time. Sodium dodecylbenzene sulfonate (SDBS) was added to enhance the stabilization of the aqueous suspension. A surface condensation reaction between amino and carboxylic groups was then performed by immersing an amino self-assembled monolayer (SAM)-modified gold eletrode into the aqueous suspension of SWNTs with the aid of N-(3-Dimethylaminopropyl)-N’-ethylcarbodiimide hydrochloride (EDC.HC1) and sulfo-N-hydroxysuccinimide (s-NHS), thereafter SWNTs has been immobilized on gold oriently. Poly(3,4-ethylenedioxythiophene) (PEDOT) films were prepared on the SWNT-immoblized electrode by potentiostatic electropolymerization from EDOT aqueous solution, with p-toluene sulfonic acid sodium salt (TsONa) as the supporting electrolytes.Field Emission-scanning electron microscopy (FSEM), transmission electron microscopy (TEM), infrared spectrometry and raman spectrometry were used to characterize the structure and modality of SWNTs before and after acid treatment. Raman spectrometry could also testify the immobilization of SWNTs on gold while atomic force microscopy (AFM) showed the perpendicular standing state of SWNTs on gold surface. Scanning electron microscopy (SEM) was used for observing the rough surface after polymerization of EDOT on modified gold andthe results of cyclic voltammetry (CV) showed that all the modified electrodeshave remarkable improvements in electrochemistry properties.

Carbon nanotube possesses extremely high elastic modulus and toughness. Its elastic modulus can be up to about 1 TPa and elastic strain can be up to 5%, at most 12%. So the application foreground of carbon nanotubes will be great. On the aspect of engineering utilization, the special electronic, photophysical and mechanical characteristics of carbon nanotube make it very sensitive to its structural feature and deformation behavior. Because of this, the application result of carbon nanotube proub has a great relationship with the deformation character of carbon nanotube under external forces.In this paper, two dynamic stability models of carbon nanotube under small-scale effect are formulated respectively, based on non-local classical shell theory and non-local Donnell shell theory. Also the related dynamic stability basic equations of carbon nanotubes are derived. The solutions of the basic equations with the condition that axial periodic force equals zero are get in the real situation examples. Then the dynamic stability critical frequencies of carbon nanotube under the situation that axial periodic force does not equal zero are solved from the basic equations too. A kind of effective method for multi-walled carbon nanotubes is utilized to solve the dynamic stability problem of multi-walled carbon nanotubes. The solution of effective method and the accurate solution which considered van der Waals force are compared and discussed.Through the comparison of solutions based on the two different theories, the parameter condition under which non-local Donnell shell theory can replace non-local classical shell theory are get. Through the analysis of calculation results, we can find that when the axial periodic force equals zero, the small-scale effect on dynamic critical frequencies of carbon nanotube will gradually decrease with the increase of length-diameter ratio L / Rof carbon nanotube. When the amplitude of dynamic axial force increases proportionally, dynamic critical frequencies of carbon nanotube will basically increase proportionally too. Through the comparison between the calculation results of non-local Donnell shell theory and non-local classical shell theory, we can find that the result curve of these two theories are mainly the same. So for the study of dynamic stability of carbon nanotube, the calculation method of non-local Donnell shell theory can replace the calculation method of non-local classical shell theory in certain conditions, which can simplify the course of calculation and save time.This paper studies the dynamic stability calculation method and results of sngle-walled carbon nanotube and multi-walled carbon nanoTubes based on different non-local shell models. The study results possess certain theoretical and engineering application values for the application of carbon nanotube as probes in different engineering aspects.

Carbon nanotubes(CNTs) have special electrocatalytic effect on some organic pollutants due to the properties of excellent adsorption capability, great specific surface and good electronic conductivity. In this thesis, MWNTs purified and shortened were by ultrasonication in mixed-acid of HNO3 and H2SO4, MWNTs were dispersed in the Nafion solution and coated on the glassy carbon electrode (GCE) .Operational parameters were optimized and the electrochemical behaviors of p-cresol and m-cresol were studied by cyclic voltammetry (CV) and chronoamperometry (CA).The peak current were linearly proportional to the concentrations of p-cresol in the range from 2.0×10?7~2.0×10?4 mol/L and of m-cresol from 4.0×10?7~1.5×10?4 mol/L , with detection limits respectively of 7.0×10?8 and 1.0×10?7mol/L.Meanwhile, many metal nanoparticles have been used to catalyze the reaction of small organic molecules and enhance the reaction efficiency. As CNTs are promising ideal supporting material, then platinum particles dispersed on MWNTs/GCE will catalyse greatly the reaction of some organic molecules. In the article, platinum particles were electrodeposited on MWNTs/GCE by CV, which was denoted as Pt/MWNTs/GCE. The factors influencing the electrodeposition of the platinum particles were discussed. CV and electrochemical impedeance spectra(EIS) were employed to characterize the modified electrodes. The electrochemical behaviors of low concentration of HCHO and CH3OH on the modified electrode were studied.The results indicated that the electrodes modified with the composite film exhibited an obvious electrocatalytic capability. The peak current at Pt/MWNTs/GCE is 3.5 times of that at Pt/GCE. The effect of experimental conditions on peak current was studied.The peak current were linearly proportional to the concentration of HCHO in the range 0.2~10.0μg/mL, with a detection limit of 0.1μg/mL. Furthermore, the different methods for HCHO determination were compared. On the other hand, satisfactory results were obtained by using composite-film-modified electrode to determine the concentration of formaldehyde in simulated waste water.Moreover, in the 0.1mol/L NaOH solution, composite-film-modified electrode also exhibited an excellent elecrocatalytic capability for methanol, the peak current at Pt/MWNTs/GCE is 4 times of that at Pt/GCE, and the elecrocatalytic oxidation mechanism of low concentration methanol was discussed. The peak current was linearly proportional to the concentration of methanol in the range of 2.0×10?6~1.0×10?3mol/L, with a detection limit of 1.0×10?6 mol/L. The stability and repeatability of the composite-film-modified electrode were satisfying.

Au nanoparticles were spontaneous reduced on carbon nanotubes grown directly onsubstrate that are fabricated using electrodeposited iron particles, and it was use for nonenzymatic sensor for detection glucose. At the same time , it was researched that preparation of enzyme biosensor based on carbon nanotubes grown directly on substrate, and enzyme biosensor was applied in detection organophosphates pesticides, in this paper, manly work and achievement as follows:（1） preparation of CNTs: One-dimensional carbon materials grown directly on substrate was researched using electrodeposited Ni and Fe as catalysts. And the results indicate that products are carbon fibres using electrodeposited Ni, and products are CNTs with high pure and quality using Fe as catalysts. Diameter of CNTs are even, and CNTs are excellent carrier using as nonenzymatic sensor and nenzymatic sensor.（2） S-Cu-Au/CNTs/C electrode were firstly preparation using carbon nanotubes grown directly on substrate as carrier by firstly spontaneous reduction Au and secondly electrodepositing Cu. Results indicate that catalytic capability of S-Cu-Au/CNTs/C electrode are excelled over Cu-Au catalysts by traditional technique. Detection extension of glucose is 1uM-4.8mM, and detection limit is 0.5 uM（3） AChE enzyme sensor were firstly preparation using carbon nanotubes grown directly on substrate as carrier, and condition of preparation and test for AChE enzyme sensor were investigated. Detection of dichlorvos、parathion、dimethoate were carried out using AchE sensor, detection extension:1×10^-8-1×10^-3（mol/L）、1×10^-7-1×10^-3（mol/L）、1×10^-8-1×10^-3（mol/L）;detection limit:7.02×10^-9mol/L、8.5×10^-8mol/L、5.4×10^-9 mol/L

Since their discovery in 1991, carbon nanotubes （CNTs） have found great applications in many fields including chemistry, physics and material science, etc. due to their unique one-dimensional, nano tubular structure, unusual mechanical, electrical and electrochemical properties On the other hand, in vitro assays using cultured cells are of great significance for studying many aspects of cell biology and drug screening. The construction of cytocompatible interface plays a key role for the fabrication of cell-based biosensors, and could undoubtedly promote the development of tissue engineering. In this thesis, a series of studies were carried out based on carbon nanotube about its cytocompatibility and application in biomaterial and cell-sensing. Some valuable results were obtained. The main points of this thesis are summarized as follows:1. Multi-walled carbon nanotubes （MWNTs） were treated and purified with mixed acid, and the raw MWNTs and acid-treated MWNTs were characterized with FTIR. The acid-treated MWNTs were easily dispersed in water. Then the cytocompatibility of both raw MWNTs and acid-treated MWNTs on osteoblastic MG-63 cells were investigated with microscopy observation techniques and MTT experiment. It has been found that both of the MWNTs did not express obvious cytotoxicity.2. The surface modification of chitosan substrate to promote cell-chitosan interaction has great importance for extending the application of chitosan as a tissue engineering scaffold material. In this work, the direct adsorption of MWNTs on chitosan film was confirmed by quartz crystal microbalance （QCM） and scanning electron microscopy investigations. The growth behaviors of MG-63 osteoblastsic cells on pure chitosan and MWNTs-modified chitosan films were investigated with MTT assay, acridine orange （AO） staining method and morphology observation. It was found that the surface modification of chitosan with MWNTs can significantly improve the attachment, spreading and proliferation of the MG-63 cells. This provides a very simple but effective method to enhance the cell-biomaterial interaction on the chitosan substrate. The proposed MWNTs-modified chitosan substrate can also be applied to the fabrication of cell patterns, which is important for the development of cellular biosensor technology and tissue engineering applications.3. MWNTs were used for the surface modification of glassy carbon electrode （GCE） to construct a non-toxic interface for immobilization of MCF-7 cells （human breast cancer cell line）. Fluorescence microscopy observation showed that the presence of MWNTs on GCE surface significantly enhanced the attachment of MCF-7 cells, and thus an electrochemical impedance cell sensor was constructed. The attachment of cells on MWNTs-GCE resulted in increase of charge-transfer resistance （Rct） between the redox probe of Fe（CN）₆^3-/4- in electrolyte solution and electrode surface. A linear relationship was found between Rct and the logarithmic value of cell concentration ranging from 104 to 106 cell·mL^-1 with a detection limit of 7.0×10³ cell·mL^-1. EIS technique was also successfully used to monitor the growth of MCF-7 cells and evaluate the cytotoxicity of anticancer drugs using cisplatin as a model. This work implies that MWNTs-modified electrode possessed potential application for the immobilization of cells and construction of cell-based biosensor for electrochemical investigation of cell adhesion, proliferation and apoptosis.

As new carbon material, carbon nanotubes (CNTs) have great potential value in such fields as nano-materials, nano-biology, nano-chemistry and so on, owing to their superior characteristics of mechanical, electromagnetic, optical properties and thermal stability.A large variety of theories and researches have shown that CNT is becoming one of the most promising catalyst supports. The active metal particles in CNTs supported catalyst can be effectively controlled in the diameter of nanometer scale, which can significantly improve the catalytic performance. However, CNTs’application have been restricted for the reason that CNT does not dissolve in most of solvents. So, how to improve the dispersion of CNTs in the solvents is critical for CNTs used as support.In this thesis, modification treatment of CNTs is investigated in different ways such as long time azeotropic reflux with nitric acid; reflux with sulfuric acid in N2 atmosphere; reflux with sodium hydroxide solution and immersion into hydrogen peroxide under ultrasonification environment. The modified CNTs were characterized by BET, TEM and IR and the results showed that CNTs treated by H2O2 or NaOH and followed by azeotropic reflux in wt.60% nitric acid had bigger specific surface area and ordered arrangement than as-purchased ones. The long tube was cut off showing open tips and functional groups like -OH, -COOH, etc. appreared on the surface to inrease its defect sites. So the solubility of the modified CNTs in different solvents is greatly improved and the functional groups on the surface defects provide more anchor sites for active metal loading on CNTs surface.Co-based catalysts supported on the modified CNTs were prepared and the effect of pH value and promoter La on the catalyst performance were investigated. The results showed that, La and ammonia could effectively avoid the aggregation of Co particles and increase the dispersion of Co on the surface of CNTs.

As a common industrial material, the epoxy resins are widely used in the field of the chemical engineering. Yet owing to the great amount of the epoxy group and the mass of the crosslinkage the epoxy resin are of large fragile and poor impact resistance and thermal resistance. While the carbon nanotubes, ever since they were found, have been admired for the excellent mechanical property, electronic property and so forth. In this paper, we took use of the carbon nanotubes and the epoxy resin to prepare a new kind of composite which is of great performance in the mechanical property, electronic property, and some operations were taken on as well to calculate some regular pattern in the formation of the network.In the research we improved the mechanical property, electronic property through the preparation of the carbon nanotube/ bismaleimide (BMI) blending system. What’s more, we synthesized a new kind of carbon nanotube /diphenyl-methane-diisocyanate (MDI) composite based on the carbon nanotubes and diphenyl-methane-diisocyanate. Firstly, we treated the carbon nanotubes with the oxidizing acid and combined the carbon nanotubes with the diphenyl-methane-diisocyanate in dry N, N-Dimethylformamide (DMF). Besides, we combined the epoxy resin and the carbon nanotubes as well. And finally we took the two products and some assistant agent into curing and got the composites.In addition, we discussed the mechanical property, electronic property as well as the thermal property of the composite and worked on the Scanning Electron Microscopy (SEM) and Transmission Electron Microscopy (TEM) images, and reached up to the mechanisms of the content of carbon nanotubes, the carboxyl-terminated butadiene-acrylonitrile (CTBN) and the different process of the preparation and curing to get a goal of the best condition of the processing of the composite.